Instruction: what is the prompt that generates the input?

Input: Recent observations have demonstrated a significant growth in the integratedstellar mass of the red sequence since z=1, dominated by a steadily increasingnumber of galaxies with stellar masses M* < 10^11 M_sun. In this paper, we usethe COMBO-17 photometric redshift survey in conjunction with deep Spitzer 24micron data to explore the relationship between star formation and the growthof stellar mass. We calculate `star formation rate functions' in four differentredshift slices, splitting also into contributions from the red sequence andblue cloud for the first time. We find that the growth of stellar mass sincez=1 is consistent with the integrated star formation rate. Yet, most of thestars formed are in blue cloud galaxies. If the stellar mass already in, andformed in, z<1 blue cloud galaxies were to stay in the blue cloud the totalstellar mass in blue galaxies would be dramatically overproduced. We explorethe expected evolution of stellar mass functions, finding that in this picturethe number of massive M* > 3x10^10 M_sun blue galaxies would also beoverproduced; i.e., most of the new stars formed in blue cloud galaxies are inthe massive galaxies. We explore a simple truncation scenario in which these`extra' blue galaxies have their star formation suppressed by an unspecifiedmechanism or mechanisms; simple cessation of star formation in these extra bluegalaxies is approximately sufficient to build up the red sequence at M*<10^11M_sun.


Instruction: what is the prompt that generates the input?

Input: A non-Hermitian complex symmetric 2x2 matrix toy model is used to studyprojective Hilbert space structures in the vicinity of exceptional points(EPs). The bi-orthogonal eigenvectors of a diagonalizable matrix arePuiseux-expanded in terms of the root vectors at the EP. It is shown that theapparent contradiction between the two incompatible normalization conditionswith finite and singular behavior in the EP-limit can be resolved byprojectively extending the original Hilbert space. The complementarynormalization conditions correspond then to two different affine charts of thisenlarged projective Hilbert space. Geometric phase and phase jump behavior areanalyzed and the usefulness of the phase rigidity as measure for the distanceto EP configurations is demonstrated. Finally, EP-related aspects ofPT-symmetrically extended Quantum Mechanics are discussed and a conjectureconcerning the quantum brachistochrone problem is formulated.


Instruction: what is the prompt that generates the input?

Input: We have analyzed the HI aperture synthesis image of the Large MagellanicCloud (LMC), using an objective and quantitative measure of topology tounderstand the HI distribution hosting a number of holes and clumps of varioussizes in the medium. The HI distribution shows different topology at fourdifferent chosen scales. At the smallest scales explored (19-29 pc), the HImass is distributed in such a way that numerous clumps are embedded on top of alow density background. At the larger scales from 73 to 194 pc, it shows ageneric hole topology. These holes might have been formed mainly by stellarwinds from hot stars. At the scales from 240 to 340 pc, slightly above the diskscale-height of the gaseous disk, major clumps in the HI map change thedistribution to have a slight clump topology. These clumps include the giantcloud associations in the spiral arms and the thick filaments surroundingsuperholes. At the largest scales studied (390-485 pc), the hole topology ispresent again. Responsible to the hole topology at this scale are a fewsuperholes which seem mainly associated with supernova explosions in the outerdisk. The gaps between the bar and spiral arms have a minor effect on thetopology at this scale.


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Input: Let L be an ample holomorphic line bundle over a compact complex Hermitianmanifold X. Any fixed smooth Hermitian metric on L induces a Hilbert spacestructure on the space of global holomorphic sections with values in the k:thtensor power of L. In this paper various convergence results are obtained forthe corresponding Bergman kernels. The convergence is studied in the large klimit and is expressed in terms of the equilibrium metric associated to thefixed metric, as well as in terms of the Monge-Ampere measure of the fixedmetric itself on a certain support set. It is also shown that the equilibriummetric has Lipschitz continuous first derivatives. These results can be seen asgeneralizations of well-known results concerning the case when the curvature ofthe fixed metric is positive (the corresponding equilibrium metric is thensimply the fixed metric itself).


Instruction: what is the prompt that generates the input?

Input: We study 7 Gamma Ray Bursts (GRBs), detected both by the BATSE instrument,on-board the Compton Gamma Ray Observatory, and by the Wide Field Camera (WFC),on-board BeppoSAX. These bursts have measured spectroscopic redshifts and are asizeable fraction of the bursts defining the correlation between the peakenergy E_peak (i.e. the peak of the vFv spectrum) and the total promptisotropic energy E_iso (the so called "Amati" relation). Recent theoreticalinterpretations of this correlation assume that black-body emission dominatesthe time resolved spectra of GRBs, even if, in the time integrated spectrum,its presence may be hidden by the change of its temperature and by the dilutionof a possible non-thermal power law component. We perform a time resolvedspectral analysis, and show that the sum of a power-law and a black-body givesacceptable fits to the time dependent spectra within the BATSE energy range,but overpredicts the flux in the WFC X-ray range. Moreover, a fit with a cutoffpower-law plus a black-body is consistent with the WFC data, but the black-bodycomponent contributes a negligible fraction of the total flux. On the contrary,we find that fitting the spectra with a Band model or a simple cutoff power-lawmodel yields an X-ray flux and spectral slope which well matches the WFCspectra.


Instruction: what is the prompt that generates the input?

Input: A concentration graph associated with a random vector is an undirected graphwhere each vertex corresponds to one random variable in the vector. The absenceof an edge between any pair of vertices (or variables) is equivalent to fullconditional independence between these two variables given all the othervariables. In the multivariate Gaussian case, the absence of an edgecorresponds to a zero coefficient in the precision matrix, which is the inverseof the covariance matrix. It is well known that this concentration graphrepresents some of the conditional independencies in the distribution of theassociated random vector. These conditional independencies correspond to the"separations" or absence of edges in that graph. In this paper we assume thatthere are no other independencies present in the probability distribution thanthose represented by the graph. This property is called the perfectMarkovianity of the probability distribution with respect to the associatedconcentration graph. We prove in this paper that this particular concentrationgraph, the one associated with a perfect Markov distribution, can be determinedby only conditioning on a limited number of variables. We demonstrate that thisnumber is equal to the maximum size of the minimal separators in theconcentration graph.


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Input: Mixed action lattice calculations allow for an additive lattice spacingdependent mass renormalization of mesons composed of one sea and one valencequark, regardless of the type of fermion discretization methods used in thevalence and sea sectors. The value of the mass renormalization depends upon thelattice actions used. This mixed meson mass shift is an important latticeartifact to determine for mixed action calculations; because it modifies thepion mass, it plays a central role in the low energy dynamics of all hadroniccorrelation functions. We determine the leading order, $\mathcal{O}(a^2)$, andnext to leading order, $\mathcal{O}(a^2 m_\pi^2)$, additive mass shift of\textit{valence-sea} mesons for a mixed lattice action with domain-wall valencefermions and rooted staggered sea fermions, relevant to the majority of currentlarge scale mixed action lattice efforts. We find that on the asqtad improvedcoarse MILC lattices, this additive mass shift is well parameterized in latticeunits by $\Delta(am)^2 = 0.034(2) -0.06(2) (a m_\pi)^2$, which in physicalunits, using $a=0.125$ fm, corresponds to $\Delta(m)^2 = (291\pm 8\textrm{MeV})^2 -0.06(2) m_\pi^2$. In terms of the mixed action effective fieldtheory parameters, the corresponding mass shift is given by $a^2\Delta_\mathrm{Mix} = (316 \pm 4 \textrm{MeV})^2$ at leading order plusnext-to-leading order corrections including the necessary chiral logarithms forthis mixed action calculation, determined in this work. Within the precision ofour calculation, one can not distinguish between the full next-to-leading ordereffective field theory analysis of this additive mixed meson mass shift and theparameterization given above.


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Input: In a previous work (M. Campisi. Stud. Hist. Phil. M. P. 36 (2005) 275-290) wehave addressed the mechanical foundations of equilibrium thermodynamics on thebasis of the Generalized Helmholtz Theorem. It was found that the volumeentropy provides a good mechanical analogue of thermodynamic entropy because itsatisfies the heat theorem and it is an adiabatic invariant. This propertyexplains the ``equal'' sign in Clausius principle ($S_f \geq S_i$) in a purelymechanical way and suggests that the volume entropy might explain the ``largerthan'' sign (i.e. the Law of Entropy Increase) if non adiabatic transformationswere considered. Based on the principles of microscopic (quantum or classical)mechanics here we prove that, provided the initial equilibrium satisfy thenatural condition of decreasing ordering of probabilities, the expectationvalue of the volume entropy cannot decrease for arbitrary transformationsperformed by some external sources of work on a insulated system. This can beregarded as a rigorous quantum mechanical proof of the Second Law. We discusshow this result relates to the Minimal Work Principle and improves overprevious attempts. The natural evolution of entropy is towards larger valuesbecause the natural state of matter is at positive temperature. Actually theLaw of Entropy Decrease holds in artificially prepared negative temperaturesystems.


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Input: We compare the use of galaxy asymmetry and pair proximity for measuringgalaxy merger fractions and rates for a volume limited sample of 3184 galaxieswith -21 < M(B) -5 log h < -18 mag. and 0.010 < z < 0.123 drawn from theMillennium Galaxy Catalogue. Our findings are that:  (i) Galaxies in close pairs are generally more asymmetric than isolatedgalaxies and the degree of asymmetry increases for closer pairs. At least 35%of close pairs (with projected separation of less than 20 h^{-1} kpc andvelocity difference of less than 500 km s^{-1}) show significant asymmetry andare therefore likely to be physically bound.  (ii) Among asymmetric galaxies, we find that at least 80% are eitherinteracting systems or merger remnants. However, a significant fraction ofgalaxies initially identified as asymmetric are contaminated by nearby stars orare fragmented by the source extraction algorithm. Merger rates calculated viaasymmetry indices need careful attention in order to remove the above sourcesof contamination, but are very reliable once this is carried out.  (iii) Close pairs and asymmetries represent two complementary methods ofmeasuring the merger rate. Galaxies in close pairs identify future mergers,occurring within the dynamical friction timescale, while asymmetries aresensitive to the immediate pre-merger phase and identify remnants.  (iv) The merger fraction derived via the close pair fraction and asymmetriesis about 2% for a merger rate of (5.2 +- 1.0) 10^{-4} h^3 Mpc^{-3} Gyr^{-1}.These results are marginally consistent with theoretical simulations (dependingon the merger time-scale), but imply a flat evolution of the merger rate withredshift up to z ~1.


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Input: An interplanetary (IP) type-II-like radio burst is analyzed. It occurred on2003 June 17-18 in association with a fast halo coronal mass ejection (CME), anM6.8 soft-X-ray (SXR) flare, and produced a solar proton event. Unlike coronaltype II bursts and the ma jority of IP type II radio emissions, the IPtype-II-like event associated with the fast halo CME on June 17-18 variessmoothly in time and frequency and has a frequency bandwidth that is severaltimes larger than is typical for coronal and IP type II emissions. Moreover,the frequency change with time is inconsistent with that expected from plasmaradiation associated with a CME-driven shock. I suggest that this IPtype-II-like event, referred to here as an IP type II-S event, is not due toplasma radiation but, rather, incoherent synchrotron radiation fromnear-relativistic electrons entrained in the CME magnetic field, or in thesheath region between the shock and the CME driver. This event may be anexample of a new and distinct class of interplanetary radio phenomenon.


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Input: A main distinguishing feature of a wireless network compared with a wirednetwork is its broadcast nature, in which the signal transmitted by a node mayreach several other nodes, and a node may receive signals from several othernodes simultaneously. Rather than a blessing, this feature is treated more asan interference-inducing nuisance in most wireless networks today (e.g., IEEE802.11). This paper shows that the concept of network coding can be applied atthe physical layer to turn the broadcast property into a capacity-boostingadvantage in wireless ad hoc networks. Specifically, we propose aphysical-layer network coding (PNC) scheme to coordinate transmissions amongnodes. In contrast to straightforward network coding which performs codingarithmetic on digital bit streams after they have been received, PNC makes useof the additive nature of simultaneously arriving electromagnetic (EM) wavesfor equivalent coding operation. And in doing so, PNC can potentially achieve100% and 50% throughput increases compared with traditional transmission andstraightforward network coding, respectively, in multi-hop networks. Morespecifically, the information-theoretic capacity of PNC is almost double thatof traditional transmission in the SNR region of practical interest (higherthan 0dB). We believe this is a first paper that ventures into EM-wave-basednetwork coding at the physical layer and demonstrates its potential forboosting network capacity.


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Input: The set of solutions of random constraint satisfaction problems (zero energygroundstates of mean-field diluted spin glasses) undergoes several structuralphase transitions as the amount of constraints is increased. This set firstbreaks down into a large number of well separated clusters. At the freezingtransition, which is in general distinct from the clustering one, somevariables (spins) take the same value in all solutions of a given cluster. Inthis paper we study the critical behavior around the freezing transition, whichappears in the unfrozen phase as the divergence of the sizes of therearrangements induced in response to the modification of a variable. Theformalism is developed on generic constraint satisfaction problems and appliedin particular to the random satisfiability of boolean formulas and to thecoloring of random graphs. The computation is first performed in random treeensembles, for which we underline a connection with percolation models and withthe reconstruction problem of information theory. The validity of these resultsfor the original random ensembles is then discussed in the framework of thecavity method.


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Input: We study the S=1/2 Heisenberg antiferromagnet on a square lattice withnearest-neighbor and plaquette four-spin exchanges (introduced by A.W. Sandvik,Phys. Rev. Lett. {\bf 98}, 227202 (2007).)  This model undergoes a quantum phase transition from a spontaneouslydimerized phase to N\'eel order at a critical coupling. We show that as thecritical point is approached from the dimerized side, the system exhibitsstrong fluctuations in the dimer background, reflected in the presence of alow-energy singlet mode, with a simultaneous rise in the triplet quasiparticledensity. We find that both singlet and triplet modes of high density condenseat the transition, signaling restoration of lattice symmetry. In our approach,which goes beyond mean-field theory in terms of the triplet excitations, thetransition appears sharp; however since our method breaks down near thecritical point, we argue that we cannot make a definite conclusion regardingthe order of the transition.


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Input: We study planar clusters consisting of loops including a Josephson$\pi$-junction ($\pi$-rings). Each $\pi$-ring carries a persistent current andbehaves as a classical orbital moment. The type of particular state associatedwith the orientation of orbital moments at the cluster depends on theinteraction between these orbital moments and can be easily controlled, i.e. bya bias current or by other means. We show that these systems can be describedby the two-dimensional Ising model with competing nearest-neighbor and diagonalinteractions and investigate the phase diagram of this model. Thecharacteristic features of the model are analyzed based on the exact solutionsfor small clusters such as a 5-site square plaquette as well as on a mean-fieldtype approach for the infinite square lattice of Ising spins. The results arecompared with spin patterns obtained by Monte Carlo simulations for the 100$\times$ 100 square lattice and with experiment. We show that the $\pi$-ringclusters may be used as a new type of superconducting memory elements. Theobtained results may be verified in experiments and are applicable to adiabaticquantum computing where the states are switched adiabatically with the slowchange of coupling constants.


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Input: We obtained comprehensive sets of elemental abundances for eleven dampedLy-alpha systems (DLAs) at z_DLA=1.7-2.5. In Paper I of this series, we showedfor three DLA galaxies that we can derive their star formation histories andages from a detailed comparison of their intrinsic abundance patterns withchemical evolution models. We determine in this paper the star formationproperties of six additional DLA galaxies. The derived results confirm that nosingle star formation history explains the diverse sets of abundance patternsin DLAs. We demonstrate that the various star formation histories reproducingthe DLA abundance patterns are typical of local irregular, dwarf starburst andquiescent spiral galaxies. Independent of the star formation history, the DLAshave a common characteristic of being weak star forming galaxies; models withhigh star formation efficiencies are ruled out. All the derived DLA starformation rates per unit area are moderate or low, with values between -3.2 <log SFR < -1.1 M_sol yr^{-1} kpc^{-2}. The DLA abundance patterns require alarge spread in ages ranging from 20 Myr up to 3 Gyr. The oldest DLA in oursample is observed at z_DLA=1.864 with an age estimated to more than 3 Gyr; itnicely indicates that galaxies were already forming at z_f>10. But, most of theDLAs show ages much younger than that of the Universe at the epoch ofobservation. Young galaxies thus seem to populate the high redshift Universe atz>2, suggesting relatively low redshifts of formation (z~3) for mosthigh-redshift galaxies. The DLA star formation properties are compared withthose of other high-redshift galaxies identified in deep imaging surveys withthe aim of obtaining a global picture of high-redshift objects.


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Input: The Kripke semantics of classical propositional normal modal logic is madealgebraic via an embedding of Kripke structures into the larger class ofpointed stably supported quantales. This algebraic semantics subsumes thetraditional algebraic semantics based on lattices with unary operators, and itsuggests natural interpretations of modal logic, of possible interest in theapplications, in structures that arise in geometry and analysis, such asfoliated manifolds and operator algebras, via topological groupoids and inversesemigroups. We study completeness properties of the quantale based semanticsfor the systems K, T, K4, S4, and S5, in particular obtaining an axiomatizationfor S5 which does not use negation or the modal necessity operator. Asadditional examples we describe intuitionistic propositional modal logic, thelogic of programs PDL, and the ramified temporal logic CTL.


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Input: Two approaches for closing the turbulence subgrid-scale stress tensor interms of matrix exponentials are introduced and compared. The first approach isbased on a formal solution of the stress transport equation in which theproduction terms can be integrated exactly in terms of matrix exponentials.This formal solution of the subgrid-scale stress transport equation is shown tobe useful to explore special cases, such as the response to constant velocitygradient, but neglecting pressure-strain correlations and diffusion effects.The second approach is based on an Eulerian-Lagrangian change of variables,combined with the assumption of isotropy for the conditionally averagedLagrangian velocity gradient tensor and with the `Recent Fluid Deformation'(RFD) approximation. It is shown that both approaches lead to the same basicclosure in which the stress tensor is expressed as the product of the matrixexponential of the resolved velocity gradient tensor multiplied by itstranspose. Short-time expansions of the matrix exponentials are shown toprovide an eddy-viscosity term and particular quadratic terms, and thus allow areinterpretation of traditional eddy-viscosity and nonlinear stress closures.The basic feasibility of the matrix-exponential closure is illustrated byimplementing it successfully in Large Eddy Simulation of forced isotropicturbulence. The matrix-exponential closure employs the drastic approximation ofentirely omitting the pressure-strain correlation and other `nonlinearscrambling' terms. But unlike eddy-viscosity closures, the matrix exponentialapproach provides a simple and local closure that can be derived directly fromthe stress transport equation with the production term, and using physicallymotivated assumptions about Lagrangian decorrelation and upstream isotropy.


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Input: In the canonical formalism of statistical physics, a signature of a firstorder phase transition for finite systems is the bimodal distribution of anorder parameter. Previous thermodynamical studies of nuclear sources producedin heavy-ion collisions provide information which support the existence of aphase transition in those finite nuclear systems. Some results suggest that theobservable Z1 (charge of the biggest fragment) can be considered as a reliableorder parameter of the transition. This talk will show how from peripheralcollisions studied with the INDRA detector at GSI we can obtain this bimodalbehaviour of Z1. Getting rid of the entrance channel effects and under theconstraint of an equiprobable distribution of excitation energy (E*), we usethe canonical description of a phase transition to link this bimodal behaviourwith the residual convexity of the entropy. Theoretical (with and without phasetransition) and experimental Z1-E* correlations are compared. This comparisonallows us to rule out the case without transition. Moreover that quantitativecomparison provides us with information about the coexistence region in theZ1-E* plane which is in good agreement with that obtained with the signal ofabnormal uctuations of configurational energy (microcanonical negative heatcapacity).


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Input: The Method of Invariant Grid (MIG) is an iterative procedure for modelreduction in chemical kinetics which is based on the notion of Slow InvariantManifold (SIM) [1-4]. Important role, in that method, is played by the initialgrid which, once refined, gives a description of the invariant manifold: theinvariant grid. A convenient way to get a first approximation of the SIM isgiven by the Spectral Quasi Equilibrium Manifold (SQEM) [1-2]. In the presentpaper, a flexible numerical method to construct the discrete analog of a QuasiEquilibrium Manifold, in any dimension, is presented. That object is namedQuasi Equilibrium Grid (QEG), while the procedure Quasi Equilibrium GridAlgorithm. Extensions of the QEM notion are also suggested. The QEG is anumerical tool which can be used to find a grid-based approximation for thelocus of minima of a convex function under some linear constraints. The methodis validated by construction of one and two-dimensional grids for modelhydrogen oxidation reaction.


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Input: We present a survey of mid-infrared gas-phase lines toward a sample of 76circumstellar disks around low mass pre-main sequence stars from the Spitzer"Cores to Disks" legacy program. We report the first detections of [Ne II] and[Fe I] toward classical T Tauri stars in ~20% respectively ~9% of our sources.The observed [Ne II] line fluxes and upper limits are consistent with [Ne II]excitation in an X-ray irradiated disk around stars with X-ray luminositiesL_X=10^{29}-10^{31} erg s^{-1}. [Fe I] is detected at ~10^-5-10^-4 L_Sun, butno [S I] or [Fe II] is detected down to ~10^{-6} L_Sun. The [Fe I] detectionsindicate the presence of gas-rich disks with masses of >~0.1 M_J. No H_2 0-0S(0) and S(1) disk emission is detected, except for S(1) toward one source.These data give upper limits on the warm (T~100-200K) gas mass of a few Jovianmasses, consistent with recent T Tauri disk models which include gas heating bystellar radiation. Compact disk emission of hot (T>~500K) gas is observedthrough the H_2 0-0 S(2) and/or S(3) lines toward ~8% of our sources. The linefluxes are, however, higher by more than an order of magnitude than thosepredicted by recent disk models, even when X-ray and excess UV radiation areincluded. Similarly the [Ne II]/H_2 0-0 S(2) ratios for these sources are lowerthan predicted, consistent with the presence of an additional hot molecular gascomponent not included in current disk models. Oblique shocks of stellar windsinteracting with the disk can explain many aspects of the hot gas emission, butare inconsistent with the non-detection of [S I] and [Fe II] lines.


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Input: The problem of limit shapes in the six-vertex model with domain wall boundaryconditions is addressed by considering a specially tailored bulk correlationfunction, the emptiness formation probability. A closed expression of thiscorrelation function is given, both in terms of certain determinant andmultiple integral, which allows for a systematic treatment of the limit shapesof the model for full range of values of vertex weights. Specifically, we showthat for vertex weights corresponding to the free-fermion line on the phasediagram, the emptiness formation probability is related to a one-matrix modelwith a triple logarithmic singularity, or Triple Penner model. The saddle-pointanalysis of this model leads to the Arctic Circle Theorem, and itsgeneralization to the Arctic Ellipses, known previously from domino tilings.


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Input: In 1921 Blichfeldt gave an upper bound on the number of integral pointscontained in a convex body in terms of the volume of the body. More precisely,he showed that $#(K\cap\Z^n)\leq n! \vol(K)+n$, whenever $K\subset\R^n$ is aconvex body containing $n+1$ affinely independent integral points. Here weprove an analogous inequality with respect to the surface area $\F(K)$, namely$ #(K\cap\Z^n) < \vol(K) + ((\sqrt{n}+1)/2) (n-1)! \F(K)$. The proof is basedon a slight improvement of Blichfeldt's bound in the case when $K$ is anon-lattice translate of a lattice polytope, i.e., $K=t+P$, where$t\in\R^n\setminus\Z^n$ and $P$ is an $n$-dimensional polytope with integralvertices. Then we have $#((t+P)\cap\Z^n)\leq n! \vol(P)$.  Moreover, in the 3-dimensional case we prove a stronger inequality, namely$#(K\cap\Z^n) < \vol(K) + 2 \F(K)$.


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Input: The polarized neutron scattering in helimagnetic MnSi at low $T$ revealsexistence of a partially disordered chiral state at ambient pressure in themagnetic field applied along $<111>$ axis below the first order transition tothe non-chiral ferromagnetic state. This unexpected phenomenon is explained bythe analysis of the spin-wave spectrum. We demonstrate that the square of thespin-wave gap becomes negative under magnetic field applied along $<111>$ and$<110>$ but not along the $<100>$ direction. It is a result of competitionbetween the spin-wave interaction and cubic anisotropy. This negative signmeans an instability of the spin wave spectrum for the helix and leads to adestruction of the helical order, giving rise to the partially disordered statebelow the first order ferromagnetic transition.


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Input: We present both numerical and analytical study of graphene roughness with acrystal structure including $500 \times 500$ atoms. The roughness caneffectively result in a random gauge field and has important consequences forits electronic structure. Our results show that its height fluctuations insmall scales have scaling behavior with a temperature dependent roughnessexponent in the interval of $ 0.6 < \chi < 0.7 $. The correlation function ofheight fluctuations depends upon temperature with characteristic length scaleof $ \approx 90 {\AA}$ (at room temperature). We show that the correlationfunction of the induced gauge field has a short-range nature with correlationlength of about $\simeq 2-3 {\AA}$. We also treat the problem analytically byusing the Martin-Siggia-Rose method. The renormalization group flows did notyield any delocalized-localized transition arising from the graphene roughness.Our results are in good agreement with recent experimental observations.


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Input: Pulse shape discrimination (PSD) is one of the most distinctive features ofliquid scintillators. Since the introduction of the scintillation techniques inthe field of particle detection, many studies have been carried out tocharacterize intrinsic properties of the most common liquid scintillatormixtures in this respect. Several application methods and algorithms able toachieve optimum discrimination performances have been developed. However, thevast majority of these studies have been performed on samples of smalldimensions. The Counting Test Facility, prototype of the solar neutrinoexperiment Borexino, as a 4 ton spherical scintillation detector immersed in1000 tons of shielding water, represents a unique opportunity to extend thesmall-sample PSD studies to a large-volume setup. Specifically, in this work weconsider two different liquid scintillation mixtures employed in CTF,illustrating for both the PSD characterization results obtained either with theprocessing of the scintillation waveform through the optimum Gatti's method, orvia a more conventional approach based on the charge content of thescintillation tail. The outcomes of this study, while interesting per se, arealso of paramount importance in view of the expected Borexino detectorperformances, where PSD will be an essential tool in the framework of thebackground rejection strategy needed to achieve the required sensitivity to thesolar neutrino signals.


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Input: We consider a list decoding algorithm recently proposed by Pellikaan-Wu\cite{PW2005} for $q$-ary Reed-Muller codes $\mathcal{RM}_q(\ell, m, n)$ oflength $n \leq q^m$ when $\ell \leq q$. A simple and easily accessiblecorrectness proof is given which shows that this algorithm achieves a relativeerror-correction radius of $\tau \leq (1 - \sqrt{{\ell q^{m-1}}/{n}})$. This isan improvement over the proof using one-point Algebraic-Geometric codes givenin \cite{PW2005}. The described algorithm can be adapted to decodeProduct-Reed-Solomon codes.  We then propose a new low complexity recursive algebraic decoding algorithmfor Reed-Muller and Product-Reed-Solomon codes. Our algorithm achieves arelative error correction radius of $\tau \leq \prod_{i=1}^m (1 -\sqrt{k_i/q})$. This technique is then proved to outperform the Pellikaan-Wumethod in both complexity and error correction radius over a wide range of coderates.


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Input: The configurations of single and double bonds in polycyclic hydrocarbons areabstracted as Kekul\'e states of graphs. Sending a so-called soliton over anopen channel between ports (external nodes) of the graph changes the Kekul\'estate and therewith the set of open channels in the graph. This switchingbehaviour is proposed as a basis for molecular computation. The proposal ishighly speculative but may have tremendous impact.  Kekul\'e states with the same boundary behaviour (port assignment) can beregarded as equivalent. This gives rise to the abstraction of Kekul\'e cells.The basic theory of Kekul\'e states and Kekul\'e cells is developed here, up tothe classification of Kekul\'e cells with $\leq 4$ ports. To put the theory incontext, we generalize Kekul\'e states to semi-Kekul\'e states, which form thesolutions of a linear system of equations over the field of the bits 0 and 1.We briefly study so-called omniconjugated graphs, in which every portassignment of the right signature has a Kekul\'e state. Omniconjugated graphsmay be useful as connectors between computational elements. We finallyinvestigate some examples with potentially useful switching behaviour.


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Input: We have compiled the largest sample of multiwavelength spectral energydistributions (SEDs) of Broad Absorption Line (BAL) quasars to date, from theradio to the X-ray. We present new Spitzer MIPS (24, 70, and 160 micron)observations of 38 BAL quasars in addition to data from the literature andpublic archives. In general, the mid-infrared properties of BAL quasars areconsistent with those of non-BAL quasars of comparable luminosity. Inparticular, the optical-to-mid-infrared luminosity ratios of the twopopulations are indistinguishable. We also measure or place upper limits on thecontribution of star formation to the far-infrared power. Of 22 (57%) upperlimits, seven quasars have sufficiently sensitive constraints to conclude thatstar formation likely contributes little (<20%) to their far-infrared power.The 17 BAL quasars (45%) with detected excess far-infrared emission likely hosthyperluminous starbursts with L_fir,SF=10^{13-14} L_sun. Mid-infrared throughX-ray composite BAL quasar SEDs are presented, incorporating all of theavailable photometry. Overall, we find no compelling evidence for inherentdifferences between the SEDs of BAL vs. non-BAL quasars of comparableluminosity. Therefore a ``cocoon'' picture of a typical BAL quasar outflowwhereby the wind covers a large fraction of the sky is not supported by themid-infrared SED comparison with normal quasars, and the disk-wind paradigmwith a typical radio-quiet quasar hosting a BAL region remains viable.


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Input: Presenting theoretical arguments and numerical results we demonstratelong-range intrachain correlations in concentrated solutions and melts of longflexible polymers which cause a systematic swelling of short chain segments.They can be traced back to the incompressibility of the melt leading to aneffective repulsion $u(s) \approx s/\rho R^3(s) \approx ce/\sqrt{s}$ whenconnecting two segments together where $s$ denotes the curvilinear length of asegment, $R(s)$ its typical size, $ce \approx 1/\rho be^3$ the ``swellingcoefficient", $be$ the effective bond length and $\rho$ the monomer density.The relative deviation of the segmental size distribution from the idealGaussian chain behavior is found to be proportional to $u(s)$. The analysis ofdifferent moments of this distribution allows for a precise determination ofthe effective bond length $be$ and the swelling coefficient $ce$ ofasymptotically long chains. At striking variance to the short-range decaysuggested by Flory's ideality hypothesis the bond-bond correlation function oftwo bonds separated by $s$ monomers along the chain is found to decayalgebraically as $1/s^{3/2}$. Effects of finite chain length are consideredbriefly.


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Input: In this notes unbounded regular operators on Hilbert $C^*$-modules overarbitrary $C^*$-algebras are discussed. A densely defined operator $t$possesses an adjoint operator if the graph of $t$ is an orthogonal summand.Moreover, for a densely defined operator $t$ the graph of $t$ is orthogonallycomplemented and the range of $P_FP_{G(t)^\bot}$ is dense in its biorthogonalcomplement if and only if $t$ is regular. For a given $C^*$-algebra $\mathcalA$ any densely defined $\mathcal A$-linear closed operator $t$ between Hilbert$C^*$-modules is regular, if and only if any densely defined $\mathcalA$-linear closed operator $t$ between Hilbert $C^*$-modules admits a denselydefined adjoint operator, if and only if $\mathcal A$ is a $C^*$-algebra ofcompact operators. Some further characterizations of closed and regular modularoperators are obtained.  Changes 1: Improved results, corrected misprints, added references. Acceptedby J. Operator Theory, August 2007 / Changes 2: Filled gap in the proof of Thm.3.1, changes in the formulations of Cor. 3.2 and Thm. 3.4, updated referencesand address of the second author.


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Input: We present measurements of the mean dense core lifetimes in numericalsimulations of magnetically supercritical, turbulent, isothermal molecularclouds, in order to compare with observational determinations. "Prestellar"lifetimes (given as a function of the mean density within the cores, which inturn is determined by the density threshold n_thr used to define them) areconsistent with observationally reported values, ranging from a few to severalfree-fall times. We also present estimates of the fraction of cores in the"prestellar", "stellar'', and "failed" (those cores that redisperse back intothe environment) stages as a function of n_thr. The number ratios are measuredindirectly in the simulations due to their resolution limitations. Our approachcontains one free parameter, the lifetime of a protostellar object t_yso (Class0 + Class I stages), which is outside the realm of the simulations. Assuming avalue t_yso = 0.46 Myr, we obtain number ratios of starless to stellar coresranging from 4-5 at n_thr = 1.5 x 10^4 cm^-3 to 1 at n_thr = 1.2 x 10^5 cm^-3,again in good agreement with observational determinations. We also find thatthe mass in the failed cores is comparable to that in stellar cores at n_thr =1.5 x 10^4 cm^-3, but becomes negligible at n_thr = 1.2 x 10^5 cm^-3, inagreement with recent observational suggestions that at the latter densitiesthe cores are in general gravitationally dominated. We conclude by noting thatthe timescale for core contraction and collapse is virtually the same in thesubcritical, ambipolar diffusion-mediated model of star formation, in the modelof star formation in turbulent supercritical clouds, and in a modelintermediate between the previous two, for currently accepted values of theclouds' magnetic criticality.


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Input: Coherent Harmonic Generation (CHG), and in particular Nonlinear HarmonicGeneration (NHG), is of importance for both short wavelength Free-ElectronLasers (FELs), in relation with the achievement of shorter wavelengths with afixed electron-beam energy, and high-average power FEL resonators, in relationwith destructive effects of higher harmonics radiation on mirrors. In thispaper we present a treatment of NHG from helical wigglers with particularemphasis on the second harmonic. Our study is based on an exact analyticalsolution of Maxwell's equations, derived with the help of a Green's functionmethod. In particular, we demonstrate that nonlinear harmonic generation (NHG)from helical wigglers vanishes on axis. Our conclusion is in open contrast withresults in literature, that include a kinematical mistake in the description ofthe electron motion.


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Input: In the previous paper, based on the $SU(2)_{f}\times SU(2)_{s}$ heavy quarksymmetries of the QCD Lagrangian in the heavy quark limit, the Bethe-Salpeterequation for the heavy baryon $\Lambda_b$ was established with the picture that$\Lambda_b$ is composed of a heavy quark and a scalar light diquark. In thepresent work, we apply this model to calculate $\mu_\pi^2$ for $\Lambda_b$, theaverage kinetic energy of the heavy quark inside $\Lambda_{b}$. This quantityis particularly interesting since it can be measured in experiments and sinceit contributes to the inclusive semileptonic decays of $\Lambda_b$ whencontributions from higher order terms in $1/M_b$ expansions are taken intoaccount and consequently influences the determination of theCabibbo-Kobayashi-Maskawa matrix elements $V_{ub}$ and $V_{cb}$. We find that$\mu_\pi^2$ for $\Lambda_b$ is $0.25GeV^2$ $\sim$ $0.95GeV^2$, depending on theparameters in the model including the light diquark mass and the interactionstrength between the heavy quark and the light diquark in the kernel of the BSequation. We also find that this result is consistent with the value of$\mu_\pi^2$ for $\Lambda_b$ which is derived from the experimental value of$\mu_\pi^2$ for the $B$ meson with the aid of the heavy quark effective theory.


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Input: We study stellar configurations and the space-time around them in metric$f(R)$ theories of gravity. In particular, we focus on the polytropic model ofthe Sun in the $f(R)=R-\mu^4/R$ model. We show how the stellar configuration inthe $f(R)$ theory can, by appropriate initial conditions, be selected to beequal to that described by the Lane-Emden -equation and how a simple scalingrelation exists between the solutions. We also derive the correct solutionanalytically near the center of the star in $f(R)$ theory. Previous analyticaland numerical results are confirmed, indicating that the space-time around theSun is incompatible with Solar System constraints on the properties of gravity.Numerical work shows that stellar configurations, with a regular metric at thecenter, lead to $\gamma_{PPN}\simeq1/2$ outside the star ie. theSchwarzschild-de Sitter -space-time is not the correct vacuum solution for suchconfigurations. Conversely, by selecting the Schwarzschild-de Sitter -metric asthe outside solution, we find that the stellar configuration is unchanged butthe metric is irregular at the center. The possibility of constructing a $f(R)$theory compatible with the Solar System experiments and possible newconstraints arising from the radius-mass -relation of stellar objects isdiscussed.


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Input: Competitive random sequential adsorption on a line from a binary mix ofincident particles is studied using both an analytic recursive approach andMonte Carlo simulations. We find a strong correlation between the small and thelarge particle distributions so that while both partial contributions to thefill factor fluctuate widely, the variance of the total fill factor remainsrelatively small. The variances of partial contributions themselves are quitedifferent between the smaller and the larger particles, with the largerparticle distribution being more correlated. The disparity in fluctuations ofpartial fill factors increases with the particle size ratio. The additionalvariance in the partial contribution of smaller particle originates from thefluctuations in the size of gaps between larger particles. We discuss theimplications of our results to semiconductor high-energy gamma detectors wherethe detector energy resolution is controlled by correlations in the cascadeenergy branching process.


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Input: We determine the contribution of stars in galaxies, intracluster stars, andthe intracluster medium to the total baryon budget in nearby galaxy clustersand groups. We find that the baryon mass fraction (f_b) within r500 is constantfor systems with M500 between 6e13 and 1e15 Msun. Although f_b is lower thanthe WMAP value, the shortfall is on the order of both the observationalsystematic uncertainties and the depletion of baryons within r500 that ispredicted by simulations. The data therefore provide no compelling evidence forundetected baryonic components, particularly any that vary in importance withcluster mass. A unique feature of the current analysis is direct inclusion ofthe contribution of intracluster light (ICL) in the baryon budget. The increasein X-ray gas mass fraction with increasing total mass is entirely accounted forby a decrease in the total stellar mass fraction, supporting the argument thatthe behavior of both the stellar and X-ray gas components is dominated by adecrease in star formation efficiency in more massive environments. Within justthe stellar component, the fraction of the total stellar luminosity in the BCGand ICL decreases as velocity dispersion increases, suggesting that the BCG+ICLcomponent, and in particular the dominant ICL component, grows less efficientlyin higher mass environments. The degree to which this behavior arises from oursample selection, which favored systems with central, giant ellipticalgalaxies, remains unclear. A more robust result is the identification of lowmass groups with large BCG+ICL components, demonstrating that the creation ofintracluster stars does not require a massive cluster environment. Within r500and r200, the BCG+ICL contributes on average 40% and 33% of the total stellarlight, respectively.


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Input: The observed apparent velocities and luminosities of the relativistic jets inAGNs are significantly different from their intrinsic values due to strongspecial relativistic effects. We adopt the maximum likelihood method todetermine simultaneously the intrinsic luminosity function and the Lorentzfactor distribution of a sample of AGNs. The values of the best estimatedparameters are consistent with the previous results, but with much betteraccuracy. In previous study, it was assumed that the shape of the observedluminosity function of Fanaroff-Riley type II radio galaxies is the same withthe intrinsic luminosity function of radio loud quasars. Our results prove thevalidity of this assumption. We also find that low and high redshift groupsdivided by z=0.1 are likely to be from different parent populations.


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Input: Let G be a simple and simply-connected complex algebraic group, P \subset G aparabolic subgroup. We prove an unpublished result of D. Peterson which statesthat the quantum cohomology QH^*(G/P) of a flag variety is, up to localization,a quotient of the homology H_*(Gr_G) of the affine Grassmannian \Gr_G of G. Asa consequence, all three-point genus zero Gromov-Witten invariants of $G/P$ areidentified with homology Schubert structure constants of H_*(Gr_G),establishing the equivalence of the quantum and homology affine Schubertcalculi.  For the case G = B, we use the Mihalcea's equivariant quantum Chevalleyformula for QH^*(G/B), together with relationships between the quantum Bruhatgraph of Brenti, Fomin and Postnikov and the Bruhat order on the affine Weylgroup. As byproducts we obtain formulae for affine Schubert homology classes interms of quantum Schubert polynomials. We give some applications in quantumcohomology.  Our main results extend to the torus-equivariant setting.


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Input: We theoretically discuss how to tune the competition between Forster transferand spontaneous emission in a continuous and nondestructive fashion. Theproposed approach is especially suitable for delicate biological systems likelight harvesting complexes and fluorescent protein oligomers. We demonstratethat the manipulation of the density of photonic states at the emissionfrequency of the energy donor results in a change of the quantum efficienciesof the competing energy transfer and spontaneous emission processes. Thischange will be manifested in a modification of the donor and acceptor emissionintensities. Thus, by controlling the local density of photonic states Forstercoupled systems can be manipulated and analyzed without the need to physicallyseparate donor and acceptor chromophores for individual analysis, which is ofinterest, for example, for oligomeric reef coral fluorescent proteins.


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Input: A new system, consisting of a double channel Fabry Perot etalon and laserdiodes emitting around 780 nm is described and proposed to be used for airrefractive index measurements. The principle of this refractometer is based onfrequency measurements between optical laser sources. It permitsquasi-instantaneous measurement with a resolution better than and uncertaintyin the range. Some preliminary results on the stability of this system and themeasurements of the refractive index of air with this apparatus are presented.The first measurements of the index of air at 780 nm are, within anexperimental uncertainty of the order of, in agreement with the predictedvalues by the so-called revised Edl\'en equations. This result is to the bestof our knowledge the first to extend to the near infra-red the validity of therevised Edl\'en equation derived for the wavelength range 350- 650 nm.


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Input: [ABRIDGED] We recently presented evidence of a connection between thebrightness profiles of nearby early-type galaxies and the properties of the AGNthey host. The radio loudness of the AGN appears to be univocally related tothe host's brightness profile: radio-loud nuclei are only hosted by ``core''galaxies while radio-quiet AGN are only found in ``power-law'' galaxies. Weextend our analysis here to a sample of 42 nearby (V < 7000 km/s) Seyfertgalaxies hosted by early-type galaxies. We used the available HST images tostudy their brightness profiles. Having excluded complex and highly nucleatedgalaxies, in the remaining 16 objects the brightness profiles can besuccessfully modeled with a Nuker law with a steep nuclear cusp characteristicof ``power-law'' galaxies (with logarithmic slope 0.51 - 1.07). This result iswhat is expected for these radio-quiet AGN based on our previous findings, thusextending the validity of the connection between brightness profile and radioloudness to AGN of a far higher luminosity. We explored the robustness of thisresult against a different choice of the analytic form for the brightnessprofiles, using a Sersic law. In no object could we find evidence of a centrallight deficit with respect to a pure Sersic model, the defining feature of``core'' galaxies in this modeling framework. We conclude that, regardless ofthe modeling strategy, the dichotomy of AGN radio loudness can be univocallyrelated to the host's brightness profile. Our general results can be re-phrasedas ``radio-loud nuclei are hosted by core galaxies, while radio-quiet AGN arefound in non-core galaxies''.


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Input: We consider a model of socially interacting individuals that make a binarychoice in a context of positive additive endogenous externalities. Itencompasses as particular cases several models from the sociology and economicsliterature. We extend previous results to the case of a general distribution ofidiosyncratic preferences, called here Idiosyncratic Willingnesses to Pay(IWP). Positive additive externalities yield a family of inverse demand curvesthat include the classical downward sloping ones but also new ones with nonconstant convexity. When j, the ratio of the social influence strength to thestandard deviation of the IWP distribution, is small enough, the inverse demandis a classical monotonic (decreasing) function of the adoption rate. Even ifthe IWP distribution is mono-modal, there is a critical value of j above whichthe inverse demand is non monotonic, decreasing for small and high adoptionrates, but increasing within some intermediate range. Depending on the pricethere are thus either one or two equilibria. Beyond this first result, weexhibit the generic properties of the boundaries limiting the regions where thesystem presents different types of equilibria (unique or multiple). Theseproperties are shown to depend only on qualitative features of the IWPdistribution: modality (number of maxima), smoothness and type of support(compact or infinite). The main results are summarized as phase diagrams in thespace of the model parameters, on which the regions of multiple equilibria areprecisely delimited.


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Input: Solar prominences and filaments (prominences projected against the solardisk) exhibit a large variety of fine structures which are well observed downto the resolution limit of ground-based telescopes. We describe themorphological aspects of these fine structures which basically depend on thetype of a prominence (quiescent or active-region). Then we review currenttheoretical scenarios which are aimed at explaining the nature of thesestructures. In particular we discuss in detail the relative roles of magneticpressure and gas pressure (i.e., the value of the plasma-beta), as well as thedynamical aspects of the fine structures. Special attention is paid to recentnumerical simulations which include a complex magnetic topology, energy balance(heating and cooling processes), as well as the multidimensional radiativetransfer. Finally, we also show how new ground-based and space observations canreveal various physical aspects of the fine structures including theirprominence-corona transition regions in relation to the orientation of themagnetic field.


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Input: It is widely believed that the perovskite Sr$_2$RuO$_4$ is an unconventionalsuperconductor with broken time reversal symmetry. It has been predicted thatsuperconductors with broken time reversal symmetry should have spontaneouslygenerated supercurrents at edges and domain walls. We have done careful imagingof the magnetic fields above Sr$_2$RuO$_4$ single crystals using scanning Hallbar and SQUID microscopies, and see no evidence for such spontaneouslygenerated supercurrents. We use the results from our magnetic imaging to placeupper limits on the spontaneously generated supercurrents at edges and domainwalls as a function of domain size. For a single domain, this upper limit isbelow the predicted signal by two orders of magnitude. We speculate on thecauses and implications of the lack of large spontaneous supercurrents in thisvery interesting superconducting system.


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Input: The observed association of Long Gamma-Ray Bursts (LGRBs) with peculiar TypeIc supernovae gives support to Woosley`s collapsar/hypernova model, in whichthe GRB is produced by the collapse of the rapidly rotating core of a massivestar to a black hole. The association of LGRBs with small star-forming galaxiessuggests low-metallicity to be a condition for a massive star to evolve to thecollapsar stage. Both completely-mixed single star models and binary starmodels are possible. In binary models the progenitor of the GRB is a massivehelium star with a close companion. We find that tidal synchronization duringcore-helium burning is reached on a short timescale (less than a fewmillennia). However, the strong core-envelope coupling in the subsequentevolutionary stages is likely to rule out helium stars with main-sequencecompanions as progenitors of hypernovae/GRBs. On the other hand, helium starsin close binaries with a neutron-star or black-hole companion can, despite thestrong core-envelope coupling in the post-helium burning phase, retainsufficient core angular momentum to produce a hypernova/GRB.


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Input: Context. Swift data are revolutionising our understanding of Gamma RayBursts. Since bursts fade rapidly, it is desirable to create and disseminateaccurate light curves rapidly.  Aims. To provide the community with an online repository of X-ray lightcurves obtained with Swift. The light curves should be of the quality expectedof published data, but automatically created and updated so as to beself-consistent and rapidly available. Methods. We have produced a suite ofprograms which automatically generates Swift/XRT light curves of GRBs. Effectsof the damage to the CCD, automatic readout-mode switching and pile-up areappropriately handled, and the data are binned with variable bin durations, asnecessary for a fading source.  Results. The light curve repository website(http://www.swift.ac.uk/xrt_curves) contains light curves, hardness ratios anddeep images for every GRB which Swift's XRT has observed. When new GRBs aredetected, light curves are created and updated within minutes of the dataarriving at the UK Swift Science Data Centre.


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Input: We present the analysis and results of a 20 ks XMM-Newton observation ofRBS1423. X-ray spectral analysis is used to establish a significantly broadenedrelativistic iron K-alpha line from a highly ionised disk. A QSO at z=2.262 wasconsidered to be the optical counterpart of this ROSAT Bright Survey X-raysource. Based on the improved XMM-Newton source position we identified az=0.208 QSO as optical counterpart to RBS1423. The 0.2-12 keV X-ray luminosityof this radio-quiet QSO is 6x10^{44} erg/s. The XMM-EPIC spectra are welldescribed by a power law with a significantly broadened iron K-alpha line. Diskline models for both Schwarzschild and Kerr black holes require hydrogen-likeiron ions to fit the measured line profile. Significant ionisation of thereflection disk is confirmed by model fits with ionised disk models, resultingin an ionisation parameter xi~2000.


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Input: The Seyfert 2 galaxies NGC 2992 and NGC 3081 have been observed by INTEGRALand Swift. We report about the results and the comparison of the spectrum above10 keV based on INTEGRAL IBIS/ISGRI, Swift/BAT, and BeppoSAX/PDS. A spectrumcan be extracted in the X-ray energy band ranging from 1 keV up to 200 keV.Although NGC 2992 shows a complex spectrum below 10 keV, the hard tail observedby various missions exhibits a slope with photon index = 2, independent on theflux level during the observation. No cut-off is detectable up to the detectionlimit around 200 keV. In addition, NGC 3081 is detected in the INTEGRAL andSwift observation and also shows an unbroken Gamma = 1.8 spectrum up to 150keV. These two Seyfert galaxies give further evidence that a high-energycut-off in the hard X-ray spectra is often located at energies E_C >> 100 keV.In NGC 2992 a constant spectral shape is observed over a hard X-ray luminosityvariation by a factor of 11. This might indicate that the physical conditionsof the emitting hot plasma are constant, while the amount of plasma varies, dueto long-term flaring activity.


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Input: There are nine metal-deficient stars that have Li abundances well below theLi plateau that is defined by over 100 unevolved stars with temperatures above5800 K and values of [Fe/H] $<$ $-$1.0. Abundances of Be have been determinedfor most of these ultra-Li-deficient stars in order to investigate the cause ofthe Li deficiencies. High-resolution and high signal-to-noise spectra have beenobtained in the Be II spectral region near 3130 \AA for six ultra-Li-deficientstars with the Keck I telescope and its new uv-sensitive CCD on the upgradedHIRES. The spectrum synthesis technique has been used to determine Beabundances. All six stars are found to have Be deficiencies also. Two havemeasurable - but reduced - Be and four have only upper limits on Be. Theseresults are consistent with the idea that these Li- and Be-deficient stars areanalogous to blue stragglers. The stars have undergone mass transfer events (ormergers) which destroy or dilute both Li and Be. The findings cannot be matchedby the models that predict that the deficiencies are due to extra-mixing in asubset of halo stars that were initially rapid rotators, with the possibleexception of one star, G 139-8. Because the ultra-Li-deficient stars are alsoBe-deficient, they appear to be genuine outliers in population of halo starsused to determine the value of primordial Li; they no longer have the Li intheir atmospheres that was produced in the Big Bang.


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Input: We present results of the HST Advanced Camera for Surveys spectroscopicground-based redshift survey in the field of A1689. We measure 98 redshifts,increasing the number of spectroscopically confirmed objects by sixfold. Wepresent two spectra from this catalog of the Sextet Arcs, images which arisefrom a strongly-lensed Lyman Break Galaxy (LBG) at a redshift of z=3.038.Gravitational lensing by the cluster magnifies its flux by a factor of ~16 andproduces six separate images with a total r-band magnitude of r_625=21.7. Thetwo spectra, each of which represents emission from different regions of theLBG, show H I and interstellar metal absorption lines at the systemic redshift.Significant variations are seen in Ly-alpha profile across a single galaxy,ranging from strong absorption to a combination of emission plus absorption. Aspectrum of a third image close to the brightest arc shows Ly-alpha emission atthe same redshift as the LBG, arising from either another spatially distinctregion of the galaxy, or from a companion galaxy close to the LBG. Taken as agroup, the Ly-alpha equivalent width in these three spectra decreases withincreasing equivalent width of the strongest interstellar absorption lines. Wediscuss how these variations can be used to understand the physical conditionsin the LBG. Intrinsically, this LBG is faint, ~0.1L*, and forming stars at amodest rate, ~4 solar masses per year. We also detect absorption line systemstoward the Sextet Arcs at z=2.873 and z=2.534. The latter system is seen acrosstwo of our spectra.


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Input: Bars in galaxies are mainly supported by particles trapped around stableperiodic orbits. These orbits represent oscillatory motion with only onefrequency, which is the bar driving frequency, and miss free oscillations. Weshow that a similar situation takes place in double bars: particles get trappedaround parent orbits, which in this case represent oscillatory motion with twofrequencies of driving by the two bars, and which also lack free oscillations.Thus the parent orbits, which constitute the backbone of an oscillatingpotential of two independently rotating bars, are the double-frequency orbits.These orbits do not close in any reference frame, but they map onto loops,first introduced by Maciejewski & Sparke (1997). Trajectories trapped aroundthe parent double-frequency orbit map onto a set of points confined within aring surrounding the loop.


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Input: We study the propagation of nucleons and nuclei in tissue-like media within aMonte Carlo Model for Heavy-ion Therapy (MCHIT) based on the GEANT4 toolkit(version 8.2). The model takes into account fragmentation of projectile nucleiand secondary interactions of produced nuclear fragments. Model predictions arevalidated with available experimental data obtained for water and PMMA phantomsirradiated by monoenergetic carbon-ion beams. The MCHIT model describes well(1) the depth-dose distributions in water and PMMA, (2) the doses measured forfragments of certain charge, (3) the distributions of positron emitting nuclearfragments produced by carbon-ion beams, and (4) the energy spectra of secondaryneutrons measured at different angles to the beam direction. Radial doseprofiles for primary nuclei and for different projectile fragments arecalculated and discussed as possible input for evaluation of biological dosedistributions. It is shown that at the periphery of the transverse dose profileclose to the Bragg peak the dose from secondary nuclear fragments is comparableto the dose from primary nuclei.


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Input: We use Monte-Carlo simulations to study aging phenomena and the occurence ofspinglass phases in systems of single-domain ferromagnetic nanoparticles underthe combined influence of dipolar interaction and anisotropy energy, fordifferent combinations of positional and orientational disorder. We find thatthe magnetic moments oriente themselves preferably parallel to their anisotropyaxes and changes of the total magnetization are solely achieved by 180 degreeflips of the magnetic moments, as in Ising systems. Since the dipolarinteraction favorizes the formation of antiparallel chain-like structures,antiparallel chain-like patterns are frozen in at low temperatures, leading toaging phenomena characteristic for spin-glasses. Contrary to the intuition,these aging effects are more pronounced in ordered than in disorderedstructures.


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Input: A complete model of helium-like line and continuum emission has beenincorporated into the plasma simulation code Cloudy. All elements between Heand Zn are treated, any number of levels can be considered, and radiative andcollisional processes are included. This includes photoionization from alllevels, line transfer including continuum pumping and destruction by backgroundopacities, scattering, and collisional processes. The model is calculatedself-consistently along with the ionization and thermal structure of thesurrounding nebula. The result is a complete line and continuum spectrum of theplasma. Here we focus on the ions of the He I sequence and reconsider thestandard helium-like X-ray diagnostics. We first consider semi-analyticalpredictions and compare these with previous work in the low-density,optically-thin limit. We then perform numerical calculations of helium-likeX-ray emission (such as is observed in some regions of Seyferts) and predictline ratios as a function of ionizing flux, hydrogen density, and columndensity. In particular, we demonstrate that, in photoionized plasmas, the$R$-ratio, a density indicator in a collisional plasma, depends on theionization fraction and is strongly affected by optical depth for large columndensities. We also introduce the notion that the $R$-ratio is a measure of theincident continuum at UV wavelengths. The $G$-ratio, which istemperature-sensitive in a collisional plasma, is also discussed, and shown tobe strongly affected by continuum pumping and optical depth as well. Thesedistinguish a photoionized plasma from the more commonly studied collisionalcase.


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Input: We discuss the time evolution and matter-wave interference of Fermicondensates on the BEC side of Feshbach resonances for s and p-wavesuperfluids, upon release from harmonic traps. In swave systems, where theorder parameter is a complex scalar, we find that the interference patternsdepend on the relative phase of the order parameters of the condensates. Inp-wave systems involving the mixture of two-hyperfine states, we show that theinterference pattern exhibits a polarization effect depending on the relativeorientation of the two vector order parameters. Lastly, we also point out thatp-wave Fermi condensates exhibit an anisotropic expansion, reflecting thespatial anisotropy of the underlying interaction between fermions and theorbital nature of the vector order parameter. Potential applications of ourresults include systems of ultra-cold atoms that exhibit p-wave Feshbachresonances such as 6Li or 40K.


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Input: Spatially extended Ly-alpha sources that are faint and/or compact in coninuumare candidates for extremely young (~< 10^7 yrs) galaxies at high redshifts. Wepresent medium-resolution (R~2000) spectroscopy of such extended Ly-alphasources found in our previous study at z~3-5, using VLT/VIMOS. The deepspectroscopy showed that all 18 objects we observed have large equivalentwidths (EWs) exceeding 100 A. For about 30% of our sample (five objects), weidentified conspicuous asymmetry on the profiles of the Ly-alpha line. Theyshow broad wing emission components on the red side, and sharp cut-off on theblue side of the Ly-alpha line. Such asymmetry is often seen in superwindgalaxies known to date, and also consistent with a theoretical prediction ofsuperwind activity. There are eight objects (8/18 ~ 40%) that have large EWsexceeding 200 A, and no clear signature of superwind activities. Such large EWscannot be explained in terms of photo-ionization by a moderately old (>10^7yrs) stellar population, even with a top-heavy IMF or an extremely lowmetallicity. These eight objects clearly show a positive correlation betweenthe Ly-alpha luminosity and the velocity width. This suggests that these eightobjects are good candidates for forming-galaxies in a gas-cooling phase.


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Input: We study the evolution and saturation of the gluon distribution function inthe quark-gluon plasma as probed by a propagating parton and its effect on thecomputation of jet quenching or transport parameter $\hat{q}$. For thermalpartons, the saturation scale $Q^2_s$ is found to be proportional to the Debyescreening mass $\mu_D^2$. For hard probes, evolution at small $x=Q^2_s/6ET$leads to jet energy dependence of $\hat{q}$. We study this dependence for botha conformal gauge theory in weak and strong coupling limit and for (pure gluon)QCD. The energy dependence can be used to extract the shear viscosity $\eta$ ofthe medium since $\eta$ can be related to the transport parameter for thermalpartons in a transport description. We also derive upper bounds on thetransport parameter for both energetic and thermal partons. The later leads toa lower bound on shear viscosity-to-entropy density ratio which is consistentwith the conjectured lower bound $\eta/s\geq 1/4\pi$. We also discuss theimplications on the study of jet quenching at the BNL Relativistic Heavy IonCollider and the CERN Large Hadron Collider and the bulk properties of thedense matter.


Instruction: what is the prompt that generates the input?

Input: Modifications to quark and antiquark fragmentation functions due toquark-quark (antiquark) double scattering in nuclear medium are studiedsystematically up to order \cal{O}(\alpha_{s}^2)$ in deeply inelasticscattering (DIS) off nuclear targets. At the order $\cal{O}(\alpha_s^2)$,twist-four contributions from quark-quark (antiquark) rescattering also exhibitthe Landau-Pomeranchuck-Midgal (LPM) interference feature similar to gluonbremsstrahlung induced by multiple parton scattering. Compared to quark-gluonscattering, the modification, which is dominated by $t$-channel quark-quark(antiquark) scattering, is only smaller by a factor of $C_F/C_A=4/9$ times theratio of quark and gluon distributions in the medium. Such a modification isnot negligible for realistic kinematics and finite medium size. Themodifications to quark (antiquark) fragmentation functions from quark-antiquarkannihilation processes are shown to be determined by the antiquark (quark)distribution density in the medium. The asymmetry in quark and antiquarkdistributions in nuclei will lead to different modifications of quark andantiquark fragmentation functions inside a nucleus, which qualitativelyexplains the experimentally observed flavor dependence of the leading hadronsuppression in semi-inclusive DIS off nuclear targets. The quark-antiquarkannihilation processes also mix quark and gluon fragmentation functions in thelarge fractional momentum region, leading to a flavor dependence of jetquenching in heavy-ion collisions.


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Input: Of the nearby transiting exoplanets that are amenable to detailed study,TrES-2 is both the most massive and has the largest impact parameter. Wepresent z-band photometry of three transits of TrES-2. We improve upon theestimates of the planetary, stellar, and orbital parameters, in conjunctionwith the spectroscopic analysis of the host star by Sozzetti and co-workers. Wefind the planetary radius to be 1.222 +/- 0.038 R_Jup and the stellar radius tobe 1.003 +/- 0.027 R_Sun. The quoted uncertainties include the systematic errordue to the uncertainty in the stellar mass (0.980 +/- 0.062 M_Sun). The timingsof the transits have an accuracy of 25s and are consistent with a uniformperiod, thus providing a baseline for future observations with the NASA Keplersatellite, whose field of view will include TrES-2.


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Input: In this work, we introduce a special kind of quantum cloning machine calledHybrid quantum cloning machine. The introduced Hybrid quantum cloning machineor transformation is nothing but a combination of pre-existing quantum cloningtransformations. In this sense it creates its own identity in the field ofquantum cloners. Hybrid quantum cloning machine can be of two types: (i) Statedependent and (ii) State independent or Universal. We study here the above twotypes of Hybrid quantum cloning machines. Later we will show that the statedependent hybrid quantum-cloning machine can be applied on only four inputstates. We will also find in this paper another asymmetric universal quantumcloning machine constructed from the combination of optimal universal B-Hquantum cloning machine and universal anti-cloning machine. The fidelities ofthe two outputs are different and their values lie in the neighborhood of${5/6} $


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Input: "Extended Clifford algebras" are introduced as a means to obtain low MLdecoding complexity space-time block codes. Using left regular matrixrepresentations of two specific classes of extended Clifford algebras, twosystematic algebraic constructions of full diversity Distributed Space-TimeCodes (DSTCs) are provided for any power of two number of relays. The leftregular matrix representation has been shown to naturally result in space-timecodes meeting the additional constraints required for DSTCs. The DSTCs soconstructed have the salient feature of reduced Maximum Likelihood (ML)decoding complexity. In particular, the ML decoding of these codes can beperformed by applying the lattice decoder algorithm on a lattice of four timeslesser dimension than what is required in general. Moreover these codes have auniform distribution of power among the relays and in time, thus leading to alow Peak to Average Power Ratio at the relays.


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Input: In the coming decades, research in extrasolar planets aims to advance twogoals: 1) detecting and characterizing low-mass planets increasingly similar tothe Earth, and 2) improving our understanding of planet formation. We present anew planet detection method that is capable of making large advances towardsboth of these objectives and describe a modest network of telescopes that isable to make the requisite observations. In a system where a known planettransits its host star, a second planet in that system will cause the timebetween transits to vary. These transit timing variations can be used to inferthe orbital elements and mass of the perturbing planet even if it has a massthat is smaller than the mass of the Earth. This detection techniquecomplements other techniques because it is most sensitive in mean-motionresonances where, due to degeneracies, other techniques have reducedsensitivity. Small ground-based observatories have already exceeded thephotometric precision necessary to detect sub-Earth mass planets. However, TTVplanet searches are currently limited by the relatively small number ofhigh-precision transit data and insufficient observing time on existingtelescopes. These issues will be compounded as the number of known transitingplanets suitable for TTV study will increase substantially in the near future.A relatively modest investment in a ground-based network of small ($\sim 0.5{\rm m}$ telescopes could provide the needed coverage and so dramaticallyincrease the effectiveness of transit timing observations.


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Input: Intermediate resolution spectroscopy of the white dwarfSDSSJ104341.53+085558.2 contains double-peaked emission lines ofCaII8498,8542,8662 and identifies this object to be the second single whitedwarf to be surrounded by a gaseous disc of metal-rich material, similar to therecently discovered SDSSJ1228+1040. A photospheric Magnesium abundance of 0.3times the solar value, determined from the observed MgII4481 absorption line,implies that the white dwarf is accreting from the circumstellar material. Theabsence of Balmer emission lines and of photospheric HeI4471 absorptionindicates that the accreted material is depleted in volatile elements and, byanalogy with SDSS1228+1040, may be the result of the tidal disruption of anasteroid. Additional spectroscopy of the DAZ white dwarfs WD1337+705 and GD362does not reveal CaII emission lines. GD362 is one of the few cool DAZ thatdisplay strong infrared flux excess, thought to be originating in acircumstellar dust disc, and its temperature is likely too low to sublimatesufficient amounts of disc material to generate detectable CaII emission.WD1337+705 is, as SDSS1228+1040 and SDSS1043+0855, moderately hot, but has thelowest Mg abundance of those three stars, suggesting a possible correlationbetween the photospheric Mg abundance and the equivalent width of the CaIIemission triplet. Our inspection of 7360 white dwarfs from SDSS DR4 fails tounveil additional strong "metal gas disc" candidates, and implies that theseobjects are rather rare.


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Input: The PTCDA (3,4,9,10-Perylene-tetracarboxylic dianhydride) and the NTCDA(1,4,5,8-Naphtalenetetracarboxylic dianhydride) are aromatic, stable, planarand highly symmetric with unusual electrical properties. The PTCDA is asemiconductor organic crystalline of particular interest due to its excellentproperties and electronic potential that are used in optoelectronic devices andthe NTCDA it is monoclinic and its space group is similar to that of the PTCDA.Recently, alternate layers of PTCDA and NTCDA were growth forming multiplestructures of quantum wells showing a new class of materials with new opticlineal properties. Some have assured that their big utilities would be centeredin the construction of diodes and of possible guides of waves. We have carriedout calculations semi-empirical of the electronic structures and of opticproperties of the PTCDA and of the NTCDA that show us that they are structureshighly orderly polymeric, semiconductors in a negative load state (chargestate= -2)


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Input: The distribution of galaxies in position and velocity around the centers ofgalaxy clusters encodes important information about cluster mass and structure.Using the maxBCG galaxy cluster catalog identified from imaging data obtainedin the Sloan Digital Sky Survey, we study the BCG-galaxy velocity correlationfunction. By modeling its non-Gaussianity, we measure the mean and scatter invelocity dispersion at fixed richness. The mean velocity dispersion increasesfrom 202+/-10 km/s for small groups to more than 854+/-102 km/s for largeclusters. We show the scatter to be at most 40.5+/-3.5%, declining to14.9+/-9.4% in the richest bins. We test our methods in the C4 cluster catalog,a spectroscopic cluster catalog produced from the Sloan Digital Sky Survey DR2spectroscopic sample, and in mock galaxy catalogs constructed from N-bodysimulations. Our methods are robust, measuring the scatter to well withinone-sigma of the true value, and the mean to within 10%, in the mock catalogs.By convolving the scatter in velocity dispersion at fixed richness with theobserved richness space density function, we measure the velocity dispersionfunction of the maxBCG galaxy clusters. Although velocity dispersion andrichness do not form a true mass-observable relation, the relationship betweenvelocity dispersion and mass is theoretically well characterized and has lowscatter. Thus our results provide a key link between theory and observations upto the velocity bias between dark matter and galaxies.


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Input: A complex manifold Y satisfies the Convex Approximation Property (CAP) ifevery holomorphic map from a neighborhood of a compact convex set K in acomplex Euclidean space C^n to Y can be approximated, uniformly on K, by entiremaps from C^n to Y. If X is a reduced Stein space and Z is a stratifiedholomorphic fiber bundle over X all of whose fibers satisfy CAP, then sectionsof Z over X enjoy the Oka property with (jet) interpolation and approximation.Previously this has been proved by the author in the case when X is a Steinmanifold without singularities (Ann. Math., 163 (2006), 689-707,math.CV/0402278; Ann. Inst. Fourier, 55 (2005), 733-751, math.CV/0411048). Wealso give existence results for holomorphic sections under certain connectivityhypothesis on the fibers. In the final part of the paper we obtain the Okaproperty for sections of submersions with stratified sprays over Stein spaces.


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Input: When a family of non symmetrical heterocycled compounds is investigated, avariety of mesophases can be observed with rather different features. Here wereport the behaviour of seven different members among a family of suchmaterials, that consists of mesomorphic oxadiazole compounds. In two of thesecompounds, the optical microscope investigation shows very interestingbehaviours. In their smectic phases, fan-shaped and toric textures, sometimeswith periodic instability, are observed. Moreover, the nematic phase displays atexture transition. Texture transitions have been previously observed onlyinside the nematic phase of some compounds belonging to the families of theoxybenzoic and cyclohexane acids. In these two oxadiazole compounds we canobserve what we define as a "toric nematic phase", heating the samples from thesmectic phase. The toric nematic texture disappears as the sample is furtherheated, changing into a smooth texture.


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Input: We study the effect of continuous quantum error correction in the case whereeach qubit in a codeword is subject to a general Hamiltonian interaction withan independent bath. We first consider the scheme in the case of a trivialsingle-qubit code, which provides useful insights into the workings ofcontinuous error correction and the difference between Markovian andnon-Markovian decoherence. We then study the model of a bit-flip code with eachqubit coupled to an independent bath qubit and subject to continuouscorrection, and find its solution. We show that for sufficiently largeerror-correction rates, the encoded state approximately follows an evolution ofthe type of a single decohering qubit, but with an effectively decreasedcoupling constant. The factor by which the coupling constant is decreasedscales quadratically with the error-correction rate. This is compared to thecase of Markovian noise, where the decoherence rate is effectively decreased bya factor which scales only linearly with the rate of error correction. Thequadratic enhancement depends on the existence of a Zeno regime in theHamiltonian evolution which is absent in purely Markovian dynamics. We analyzethe range of validity of this result and identify two relevant time scales.Finally, we extend the result to more general codes and argue that theperformance of continuous error correction will exhibit the same qualitativecharacteristics.


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Input: We report a high-resolution neutron diffraction study on theorbitally-degenerate spin-1/2 hexagonal antiferromagnet AgNiO2. A structuraltransition to a tripled unit cell with expanded and contracted NiO6 octahedraindicates root(3) x root(3) charge order on the Ni triangular lattice. Thissuggests charge order as a possible mechanism of lifting the orbital degeneracyin the presence of charge fluctuations, as an alternative to Jahn-Tellerdistortions. A novel magnetic ground state is observed at base temperatureswith the electron-rich S = 1 Ni sites arranged in alternating ferromagneticrows on a triangular lattice, surrounded by a honeycomb network of non-magneticand metallic Ni ions. We also report first-principles band-structurecalculations that explain microscopically the origin of these phenomena.


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Input: We propose that Crab giant pulses are generated on closed magnetic fieldlines near the light cylinder via anomalous cyclotron resonance on the ordinarymode. Waves are generated in a set of fine, unequally spaced, narrow emissionbands at frequencies much lower than a local cyclotron frequency. Location ofemission bands is fitted to spectral structures seen by Eilek et al. (2006).  To reproduce the data, the required density of plasma in the giant pulsesemission region is much higher, by a factor $\sim 3 \times 10^5$, than theminimal Goldreich-Julian density. Emission is generated by a population ofhighly energetic particles with radiation-limited Lorentz factors $\gamma \sim7 \times 10^7$, produced during occasional reconnection close to the Y point,where the last closed field lines approach the light cylinder.


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Input: It has been shown that the luminosity of AGNs and the size of their broadline region obey a simple relation of the type R=a L^g, from faint Seyfertnuclei to bright quasars, allowing single-epoch determination of the centralblack hole mass M=b L^g D^2 from their luminosity L and width of H_betaemission line. Adopting this mass determination for cosmological studiesrequires the extrapolation to high z and L of a relation whose calibrationrelies so far on reverberation mapping measurements performed for L<10^46 erg/sand z<0.4. We initiated a campaign for the monitoring of a few luminous,intermediate z quasars whose apparent magnitude V<15.7 allows observations witha 1.8m telescope, aimed at proving that emission lines vary and respond tocontinuum variations even for luminosities >10^47 erg/s, and determiningeventually their M_BH from reverberation mapping. We have repeatedly performedsimultaneous observations of quasars and reference stars to determine relativevariability of continuum and emission lines. We describe the observations andmethods of analysis. For the quasars PG1634+706 and PG1247+268 we obtainlight-curves respectively for CIII], MgII and for CIV, CIII] emission lineswith the relevant continua. During 3.2 years of observation, in the former caseno continuum variability has been detected and the evidence for linevariability is marginal, while in the latter case both continuum and linevariability are detected with high significance and the line variations appearcorrelated with continuum variations. The detection of the emission linevariability in a quasar with L~10^47 erg/s encourages the prosecution of thecampaign which should provide a black hole mass estimate in other 5-6 years,constraining the M_BH-L relation in a poorly explored range of luminosity.


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Input: We microscopically model the decoherence dynamics of entangled coherentstates under the influence of vacuum fluctuation. We derive an exact masterequation with time-dependent coefficients reflecting the memory effect of theenvironment, by using the Feynman-Vernon influence functional theory in thecoherent-state representation. Under the Markovian approximation, our masterequation recovers the widely used Lindblad equation in quantum optics. We theninvestigate the non-Markovian entanglement dynamics of the quantum channel interms of the entangled coherent states under noise. Compared with the resultsin Markovian limit, it shows that the non-Markovian effect enhances thedisentanglement to the initially entangled coherent state. Our analysis alsoshows that the decoherence behaviors of the entangled coherent states dependsensitively on the symmetrical properties of the entangled coherent states aswell as the interactions between the system and the environment.


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Input: Cell colonies of bacteria, tumour cells and fungi, under nutrient limitedgrowth conditions, exhibit complex branched growth patterns. In order toinvestigate this phenomenon we present a simple hybrid cellular automaton modelof cell colony growth. In the model the growth of the colony is limited by anutrient that is consumed by the cells and which inhibits cell division if itfalls below a certain threshold. Using this model we have investigated how thenutrient consumption rate of the cells affects the growth dynamics of thecolony. We found that for low consumption rates the colony takes on a Eden-likemorphology, while for higher consumption rates the morphology of the colony isbranched with a fractal geometry. These findings are in agreement with previousresults, but the simplicity of the model presented here allows for a linearstability analysis of the system. By observing that the local growth of thecolony is proportional to the flux of the nutrient we derive an approximatedispersion relation for the growth of the colony interface. This dispersionrelation shows that the stability of the growth depends on how far the nutrientpenetrates into the colony. For low nutrient consumption rates the penetrationdistance is large, which stabilises the growth, while for high consumptionrates the penetration distance is small, which leads to unstable branchedgrowth. When the penetration distance vanishes the dispersion relation isreduced to the one describing Laplacian growth without ultra-violetregularisation. The dispersion relation was verified by measuring how theaverage branch width depends on the consumption rate of the cells and showsgood agreement between theory and simulations.


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Input: We study the cosmological evolution of a tachyon scalar field T with aDirac-Born-Infeld type lagrangian and potential V(T) coupled to a canonicallynormalized scalar field \phi with an arbitrary interaction term B(T,\phi) inthe presence of a barotropic fluid $\rb$, which can be matter or radiation. Theforce between the barotropic fluid and the scalar fields is only gravitational.We show that the dynamics is completely determine by only three parameters L1 =- V_T/ V^{3/2}, L2= - B_T /B^{3/2} and L3 =-B_{\phi}/B. We determineanalytically theconditions for $\lm_i$ under which the energy density of T,\phi and $\rb$ have the same redshift. We study the behavior of T and \phi inthe asymptotic limits for L_i and we show the numerical solution for differentinteresting cases.  The effective equation of state for the tachyon field changes due to theinteraction with the scalar field and we show that it is possible for a tachyonfield to redshift as matter in the absence of an interaction term B and asradiation when B is turned on. This result solves then the tachyonic matterproblem.


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Input: In this paper, a game-theoretic model for studying power control for wirelessdata networks in frequency-selective multipath environments is analyzed. Theuplink of an impulse-radio ultrawideband system is considered. The effects ofself-interference and multiple-access interference on the performance of Rakereceivers are investigated for synchronous systems. Focusing on energyefficiency, a noncooperative game is proposed in which users in the network areallowed to choose their transmit powers to maximize their own utilities, andthe Nash equilibrium for the proposed game is derived. It is shown that, due tothe frequency selective multipath, the noncooperative solution is achieved atdifferent signal-to-interference-plus-noise ratios, respectively of the channelrealization. A large-system analysis is performed to derive explicitexpressions for the achieved utilities. The Pareto-optimal (cooperative)solution is also discussed and compared with the noncooperative approach.


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Input: We study the relaxational critical dynamics of the three-dimensional randomanisotropy magnets with the non-conserved n-component order parameter coupledto a conserved scalar density. In the random anisotropy magnets the structuraldisorder is present in a form of local quenched anisotropy axes of randomorientation. When the anisotropy axes are randomly distributed along the edgesof the n-dimensional hypercube, asymptotical dynamical critical propertiescoincide with those of the random-site Ising model. However structural disordergives rise to considerable effects for non-asymptotic critical dynamics. Weinvestigate this phenomenon by a field-theoretical renormalization groupanalysis in the two-loop order. We study critical slowing down and obtainquantitative estimates for the effective and asymptotic critical exponents ofthe order parameter and scalar density. The results predict complex scenariosfor the effective critical exponent approaching an asymptotic regime.


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Input: We present spectroscopic observations of a massive globular cluster in thedwarf irregular galaxy Sextans B, discovered by us on Hubble Space TelescopeWide Field and Planetary Camera 2 (HST WFPC2) images. Long-slit spectra wereobtained with the SCORPIO spectrograph on the the 6-m telescope at the SpecialAstrophysical observatory of the Russian Academy of Sciences. We determine age,metallicity and alpha-element abundance ratio for the globular cluster to be $2 \pm 1$ Gyr, $-1.35 \pm 0.25$ dex, and $ 0.1 \pm 0.1$ dex, respectively. Mainphotometric and structural parameters of it were determined using our surfacephotometry on the HST images. The mass ($\sim 10^5 M \sun$), luminosity andstructural parameters appear to be typical for the globular clusters in our ownGalaxy. Our findings shed a new light on the evolutionary history of Sextans B.


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Input: Spatially resolved studies of star forming regions show that the assumptionof spherical geometry is not realistic in most cases, with a major complicationposed by the gas being ionised by multiple non-centrally located stars or starclusters. We try to isolate the effects of multiple non-centrally located starson the temperature and ionisation structure of HII regions, via theconstruction of 3D photoionisation models using the 3D Monte Carlophotoionisation code MOCASSIN. We find that the true temperature fluctuationsdue to the stellar distribution (as opposed to the large-scale temperaturegradients due to other gas properties) are small in all cases and not asignificant cause of error in metallicity studies. Strong emission lines fromHII regions are often used to study the metallicity of star-forming regions. Wecompare integrated emission line spectra from our models and quantify anysystematic errors caused by the simplifying assumption of a single, centrallocation for all ionising sources. We find that the dependence of themetallicity indicators on the ionisation parameter causes a clear bias, due tothe fact that models with a fully distributed configuration of stars alwaysdisplay lower ionisation parameters than their fully concentrated counterparts.The errors found imply that the geometrical distribution of ionisation sourcesmay partly account for the large scatter in metallicities derived usingmodel-calibrated empirical methods.


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Input: The purpose of this paper is to assess the statistical characterization ofweighted networks in terms of the generalization of the relevant parameters,namely average path length, degree distribution and clustering coefficient.Although the degree distribution and the average path length admitstraightforward generalizations, for the clustering coefficient severaldifferent definitions have been proposed in the literature. We examined thedifferent definitions and identified the similarities and differences betweenthem. In order to elucidate the significance of different definitions of theweighted clustering coefficient, we studied their dependence on the weights ofthe connections. For this purpose, we introduce the relative perturbation normof the weights as an index to assess the weight distribution. This studyrevealed new interesting statistical regularities in terms of the relativeperturbation norm useful for the statistical characterization of weightedgraphs.