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astro-ph0511489	m	our central assumption in this paper is that when a halo that contains metal - free gas ( i.e. , a halo for which no star has previously formed in any of its merger - tree progenitors ) collapses , a single massive star forms at the halo center after a cooling time . the mass of this star is assumed to be constant for ...	we examine the impact of molecular hydrogen photodissociation ( which tends to reduce cooling when a photodissociating background is produced by the first stars ) and x - ray photoheating ( which heats the atomic medium , raising the entropy of the gas before it collapses into halos ) . we find that in the cdm model su...	we estimate the maximum contribution to reionization from the first generation of massive stars , with zero metallicity , under the assumption that one of these stars forms with a fixed mass in every collapsed halo in which metal - free gas is able to cool . we assume that any halo that has already had stars previously...
astro-ph0511489	c	we have considered in this paper the maximum emissivity and the contribution to reionization that metal - free stars could make . our central assumption is that only one metal - free star is made in every halo where pristine gas is able to cool via molecular hydrogen rotovibrational lines . this is a reasonable assumpt...	we assume that any halo that has already had stars previously formed in one of their halo progenitors will form only stars with metals , which are assigned an emissivity of ionizing radiation equal to that determined at from the measured intensity of the ionizing background . the contribution of metal - free stars to t...	we estimate the maximum contribution to reionization from the first generation of massive stars , with zero metallicity , under the assumption that one of these stars forms with a fixed mass in every collapsed halo in which metal - free gas is able to cool . we assume that any halo that has already had stars previously...
0707.3046	i	in @xcite c. geiss , b. leclerc , and j. schrer initiated the study of the ( generalized ) tilting theory for preprojective algebras of dynkin type @xmath4 vis vie the cluster algebra structure of the coordinate ring of the maximal unipotent group @xmath5 attached to @xmath4 under the cartan - killing classification ;...	we evaluate the geiss - leclerc - schrer-map for _ shape modules _ over the preprojective algebra of type in terms of matrix minors arising from the block - toeplitz representation of the loop group . conjecturally these minors are among the cluster variables for coordinate rings of unipotent cells within . in so doing...	we evaluate the geiss - leclerc - schrer-map for _ shape modules _ over the preprojective algebra of type in terms of matrix minors arising from the block - toeplitz representation of the loop group . conjecturally these minors are among the cluster variables for coordinate rings of unipotent cells within . in so doing...
0811.3255	i	it is now generally believed that the power of active galactic nuclei ( agns ) is extracted through the accretion of gas onto a central supermassive black hole ( smbh ) . such energy mechanism means that agns are characterized by their strong hard x - ray emission ( @xmath3kev ) , which is widely used as direct evidenc...	we examine the accretion properties in a sample of 42 hard ( 3 - 60kev ) x - ray selected nearby broad - line agns . the energy range in the sample is harder than that usually used in the similar previous studies . we believe the sample completeness will be improved in the next few years by the ongoing _ swift and _ in...	we examine the accretion properties in a sample of 42 hard ( 3 - 60kev ) x - ray selected nearby broad - line agns . the energy range in the sample is harder than that usually used in the similar previous studies . these agns are mainly complied from the rxte all sky survey ( xss ) , and complemented by the released _ ...
0811.3255	r	table 2 lists the following items measured from the spectra . column ( 2 ) and ( 3 ) lists the equivalent widths ( ews ) of h@xmath38 and h@xmath39 , respectively . all the ews refer to the continuum level determined from the continuum fitting at the position of wavelength @xmath404861 . the line ratio rfe ( = /h@xmath...	in addition , all these hard x - ray agns are biased toward luminous objects with high eddington ratio ( mostly between 0.01 to 0.1 ) and low column density ( ) , which is most likely due to the selection effect of the surveys . the hard x - ray luminosity is consequently found to be strongly correlated with the black ...	we examine the accretion properties in a sample of 42 hard ( 3 - 60kev ) x - ray selected nearby broad - line agns . the energy range in the sample is harder than that usually used in the similar previous studies . these agns are mainly complied from the rxte all sky survey ( xss ) , and complemented by the released _ ...
0811.3255	c	the properties ( @xmath10 and @xmath9 ) of accretion onto smbh are examined in a sample of 42 hard x - ray selected ( 3 - 60kev ) broad - line agns in terms of their optical spectra taken by us . the energy range is harder than that usually used in the similar previous studies . these agns are mainly compiled from the ...	these agns are mainly complied from the rxte all sky survey ( xss ) , and complemented by the released _ integral agn catalog . the black hole masses , the tight correlation between the hard x - ray ( 3 - 20kev ) and bolometric / line luminosity is well identified in our sample . also identified is a strong inverse bal...	we examine the accretion properties in a sample of 42 hard ( 3 - 60kev ) x - ray selected nearby broad - line agns . the energy range in the sample is harder than that usually used in the similar previous studies . these agns are mainly complied from the rxte all sky survey ( xss ) , and complemented by the released _ ...
astro-ph0412613	c	we believe that this analysis is the most thorough investigation of the detectability of a trans - planckian modulation to the primordial power spectrum that has been performed to date . we consider three complementary approaches a simple grid search , a fisher matrix evaluation of the likely error ellipses , and a mo...	we focus on models of trans - planckian physics which lead to a modulated primordial spectrum . rather than looking at a generic modulated spectrum , our calculations are based on a specific model , and are intended as a case study for the sort of constraints one could hope to apply on a well - motivated model of trans...	we examine the constraints cosmological observations can place on any trans - planckian corrections to the primordial spectrum of perturbations underlying the anisotropies in the cosmic microwave background . we focus on models of trans - planckian physics which lead to a modulated primordial spectrum . rather than loo...
0710.4371	c	we have examined whether the effective low - energy hamiltonian derived from the downfolding procedure is able to describe dynamics and excitation spectra in a proper way . the calculation is performed in the three - stage scheme . in the first stage , we calculate the global electronic structure from the density funct...	we examine whether essence and quantitative aspects of electronic excitation spectra are correctly captured by an effective low - energy model constructed from an _ ab initio _ downfolding scheme . a global electronic structure is first calculated by _ ab initio _ density - functional calculations with the generalized ...	we examine whether essence and quantitative aspects of electronic excitation spectra are correctly captured by an effective low - energy model constructed from an _ ab initio _ downfolding scheme . a global electronic structure is first calculated by _ ab initio _ density - functional calculations with the generalized ...
1304.4992	i	we analyzed the anisotropic psf of suprime - cam data utilizing the dense star field data . we decomposed the psf ellipticities into three components ( the optical aberration , atmospheric turbulence , and the chip - misalignment ) in an empirical manner , and assessed the amplitude of each component . we then tested a...	we examined the anisotropic point spread function ( psf ) of suprime - cam data utilizing the dense star field data . we decompose the psf ellipticities into three components , the optical aberration , atmospheric turbulence and chip - misalignment in an empirical manner , and evaluate the amplitude of each component ....	we examined the anisotropic point spread function ( psf ) of suprime - cam data utilizing the dense star field data . we decompose the psf ellipticities into three components , the optical aberration , atmospheric turbulence and chip - misalignment in an empirical manner , and evaluate the amplitude of each component ....
1009.0125	i	this paper is concerned with a concrete characterization of continuous functions that are nonnegative on a closed set @xmath1 and its application for optimization purposes . by concrete we mean a systematic procedure , e.g. a numerical test that can be implemented by an algorithm , at least in some interesting cases . ...	we first show that a continuous function is nonnegative on a closed set if and only if ( countably many ) moment matrices of some signed measure with , are all positive semidefinite ( if is compact is an arbitrary finite borel measure with ) . in particular , we obtain a convergent explicit hierarchy of semidefinite ( ...	we first show that a continuous function is nonnegative on a closed set if and only if ( countably many ) moment matrices of some signed measure with , are all positive semidefinite ( if is compact is an arbitrary finite borel measure with ) . in particular , we obtain a convergent explicit hierarchy of semidefinite ( ...
1009.0125	c	in this paper we have presented a new characterization of nonnegativity on a closed set @xmath4 which is based on the knowledge of a single finite borel measure @xmath5 with @xmath3 . it permits to obtain a hierarchy of spectrahedra which provides a nested sequence of outer approximations of the convex cone of polynomi...	wen used in polynomial optimization on certain simple closed sets ( like e.g. , the whole space , the positive orthant , a box , a simplex , or the vertices of the hypercube ) , it provides a nonincreasing sequence of upper bounds which converges to the global minimum by solving a hierarchy of semidefinite programs wit...	we first show that a continuous function is nonnegative on a closed set if and only if ( countably many ) moment matrices of some signed measure with , are all positive semidefinite ( if is compact is an arbitrary finite borel measure with ) . in particular , we obtain a convergent explicit hierarchy of semidefinite ( ...
1203.6127	i	we consider the list decoding of one - point algebraic geometry ( ag ) codes . @xcite proposed the well - known list decoding algorithm for one - point ag codes , which consists of the interpolation step and the factorization step . the interpolation step has large computational complexity and many researchers have pro...	we also extend their unique decoding algorithm to list decoding , modify it so that it can be used with the feng - rao improved code construction , prove equality between its error correcting capability and half the minimum distance lower bound by that has not been done in the original proposal except for one - point h...	we generalize the unique decoding algorithm for one - point ag codes over the miura - kamiya curves proposed by to general one - point ag codes , without any assumption . we also extend their unique decoding algorithm to list decoding , modify it so that it can be used with the feng - rao improved code construction , p...
1203.6127	c	in this paper , we modified the unique decoding algorithm for plane ag codes in @xcite so that it can support one - point ag codes on _ any _ curve , and so that it can do the list decoding . the error correction capability of the original @xcite and our modified algorithms are also expressed in terms of the minimum di...	we generalize the unique decoding algorithm for one - point ag codes over the miura - kamiya curves proposed by to general one - point ag codes , without any assumption . the proposed one is as fast as the bms algorithm for one - point hermitian codes , and as a list decoding algorithm it is much faster than the algori...	we generalize the unique decoding algorithm for one - point ag codes over the miura - kamiya curves proposed by to general one - point ag codes , without any assumption . we also extend their unique decoding algorithm to list decoding , modify it so that it can be used with the feng - rao improved code construction , p...
math0602195	i	let @xmath2 be a graph on @xmath3 $ ] ; unless otherwise stated , we allow multiple edges and isolated vertices , but no loops . two edges @xmath4 and @xmath5 are a _ crossing _ if @xmath6 and they are a _ nesting _ if @xmath7 . if we draw the vertices of @xmath2 on a line and represent the corresponding edges by arcs ...	we give a correspondence between graphs with a given degree sequence and fillings of ferrers diagrams by nonnegative integers with prescribed row and column sums . in this setting ,-crossings and-nestings of the graph become occurrences of the identity and the antiidentity matrices in the filling . we use this to show ...	we give a correspondence between graphs with a given degree sequence and fillings of ferrers diagrams by nonnegative integers with prescribed row and column sums . in this setting ,-crossings and-nestings of the graph become occurrences of the identity and the antiidentity matrices in the filling . we use this to show ...
astro-ph0604144	i	astrophysical and laboratory plasmas which are not in ( local ) thermodynamic equilibrium require a detailed modelling of their atomic and , sometimes , molecular reactions so as to determine the level populations and ionization balance of their constituents . these in turn are basic ingredients for the physical and sp...	we have calculated partial final - state resolved radiative recombination ( rr ) rate coefficients from the initial ground and metastable levels of all elements up to and including zn , plus kr , mo , and xe , for all isoelectronic sequences up to na - like forming mg - like . the data are archived according to the ato...	we have calculated partial final - state resolved radiative recombination ( rr ) rate coefficients from the initial ground and metastable levels of all elements up to and including zn , plus kr , mo , and xe , for all isoelectronic sequences up to na - like forming mg - like . the data are archived according to the ato...
1108.4214	i	when performing molecular dynamics simulations , we distinguish between bonded and non - bonded interactions.@xcite effectively , this means that the interactions have been coarse - grained on the energy scale of the simulation . certain degrees of freedom are frozen , and we describe them as being permanent bonded . o...	bond formation can be controlled to limit the maximal functionality of a bead with respect to various bond types . concomitant with the bond dynamics , angular and dihedral interactions are dynamically introduced between newly connected triplets and quartets of beads , where the interaction type is determined from the ...	we have extended the large - scale atomic / molecular massively parallel simulator ( lammps ) to support directional bonds and dynamic bonding . the framework supports stochastic formation of new bonds , breakage of existing bonds , and conversion between bond types . bond formation can be controlled to limit the maxim...
1509.03849	i	investigations of two - dimensional systems ( 2dss ) on si surfaces began with metal - oxide - semiconductor field - effect transistors ( mosfets ) @xcite . however , the amorphous sio@xmath10/si interface severely limits the quality of the 2dss . the development @xcite of hydrogen - terminated silicon ( 111 ) [ h - si...	we have fabricated ambipolar transistors on chemically prepared hydrogen - terminated si(111 ) surfaces , in which a two - dimensional electron system ( 2des ) or a two - dimensional hole system ( 2dhs ) can be populated in the same conduction channel by changing the gate voltage of a global gate applied through a vacu...	we have fabricated ambipolar transistors on chemically prepared hydrogen - terminated si(111 ) surfaces , in which a two - dimensional electron system ( 2des ) or a two - dimensional hole system ( 2dhs ) can be populated in the same conduction channel by changing the gate voltage of a global gate applied through a vacu...
1104.0549	r	figure 2 shows the time evolution of a density isosurface for constant helical pitch with @xmath51 and @xmath74 ( cps2a ) where the time , @xmath75 , is in units of @xmath76 ( light travel time across the largest velocity shear surface radius , @xmath77 , considered in this study ) . displacement of the initial force -...	displacement of the initial force - free helical magnetic field leads to the growth of cd kink instability . we find that helically distorted density structure propagates along the jet with speed and flow structure dependent on the radius of the velocity shear surface relative to the characteristic radius of the helica...	we have investigated the influence of a velocity shear surface on the linear and non - linear development of the cd kink instability of force - free helical magnetic equilibria in 3d . in this study we follow the temporal development within a periodic computational box and concentrate on flows that are sub - alfvnic on...
1104.0549	i	we have investigated the development of the cd kink instability of a force - free helical magnetic field with a sub - alfvnic velocity shear surface located at various radii relative to the characteristic radius of the magnetic field . we restricted this study to sub - alfvnic shear as this regime is appropriate to the...	we have investigated the influence of a velocity shear surface on the linear and non - linear development of the cd kink instability of force - free helical magnetic equilibria in 3d . in this study we follow the temporal development within a periodic computational box and concentrate on flows that are sub - alfvnic on...	we have investigated the influence of a velocity shear surface on the linear and non - linear development of the cd kink instability of force - free helical magnetic equilibria in 3d . in this study we follow the temporal development within a periodic computational box and concentrate on flows that are sub - alfvnic on...
1611.08611	i	the dwarf - irregular galaxy ic 10 in cassiopeia presents one of the most active starbursts in the local group and a unique environment to study the immediate relics of the most massive stars : black holes and neutron stars in high mass x - ray binaries ( hmxbs ) . motivated by the discovery of the black hole hmxb ic 1...	we have monitored the cassiopeia dwarf galaxy ( ic 10 ) in a series of 10 _ chandra _ acis - s observations to capture its variable and transient x - ray source population , which is expected to be dominated by high mass x - ray binaries ( hmxbs ) . the observations span years 2003 - 2010 and reach a limiting luminos...	we have monitored the cassiopeia dwarf galaxy ( ic 10 ) in a series of 10 _ chandra _ acis - s observations to capture its variable and transient x - ray source population , which is expected to be dominated by high mass x - ray binaries ( hmxbs ) . we present a sample of 21 x - ray sources that are variable between ...
astro-ph9708104	r	we have constructed models using the cloudy program ( ferland 1993 ) in order to investigate the ionization of the observed species , the spectrum of the uv ionizing radiation field , and the molecular fraction of the damped ly@xmath0 absorption line system at z = 2.8115 . the column densities for the species observed ...	we have obtained a moderate resolution spectrum of the quasar pks 0528 - 250 with the red channel spectrograph on the multiple mirror telescope ( mmt ) in order to study a damped ly absorption line system at z = 2.8115 . we obtain a new upper limit for the co column density for the z = 2.8108 velocity component in the ...	we have obtained a moderate resolution spectrum of the quasar pks 0528 - 250 with the red channel spectrograph on the multiple mirror telescope ( mmt ) in order to study a damped ly absorption line system at z = 2.8115 . we obtain a new upper limit for the co column density for the z = 2.8108 velocity component in the ...
astro-ph9708104	i	our main results are the following . the ionization of different species in the a@xmath42 component of the z = 2.8115 damped ly@xmath0 system rules out the possibility that the quasar uv flux dominates the uv ionizing field in this component , i.e. the quasar should be more than @xmath166 mpc away from the damped ly@xm...	the ionization of different species in this component rules out a quasar spectral energy distribution ( sed ) as the ionization field , and implies an ultraviolet radiation field intensity a few times that of the milky way value . the ionization of different species also suggests a structure with a hot intercloud mediu...	we have obtained a moderate resolution spectrum of the quasar pks 0528 - 250 with the red channel spectrograph on the multiple mirror telescope ( mmt ) in order to study a damped ly absorption line system at z = 2.8115 . we obtain a new upper limit for the co column density for the z = 2.8108 velocity component in the ...
1002.1343	i	bl lac objects , being highly continuum - dominated , are a perennial problem for those wishing to study the evolution of agn populations . the lack of visible broad lines and , even more , the low equivalent width of host absorption features makes redshift determinations extraordinarily difficult . yet , since the con...	we have obtained high dynamic range , good natural seeing images of bl lacertae objects ( bl lacs ) to search for the agn host and thus constrain the source redshift . these objects are drawn from a sample of bright flat - spectrum radio sources that are either known ( via recent _ fermi _ lat observations ) gamma - ra...	we have obtained high dynamic range , good natural seeing images of bl lacertae objects ( bl lacs ) to search for the agn host and thus constrain the source redshift . these objects are drawn from a sample of bright flat - spectrum radio sources that are either known ( via recent _ fermi _ lat observations ) gamma - ra...
astro-ph0404148	r	the na d doublet was detected in six of the eight galaxies : ngc 1569 , ngc 1614 , ngc 4214 - 1 and -2 , ngc 4449 , ngc 5253 , and m82 . no absorption was seen in ngc 2363 or i zw 18 . we believe the na d in ngc 5253 , ngc 4214 - 1 , and specific components of ngc 1569 and ngc 4449 are likely stellar in nature , via ar...	the absorption features were separated into multiple components and separated into stellar and interstellar parts based on kinematics . we find that three of the dwarfs show outflows , with an average blueshift of 27 km s . we compare the shocked gas velocity ( v ) to the ionized gas velocity ( v ) and interpret the ve...	we have obtained high resolution echelle spectra ( r = 30,000 - 50,000 ) of the na d absorption doublet ( , 5896 ) for six dwarf starburst galaxies and two more luminous starbursts : m82 and ngc 1614 . the absorption features were separated into multiple components and separated into stellar and interstellar parts base...
astro-ph0404148	c	we have obtained high - resolution echelle spectra of six dwarf starburst galaxies , ngc 1614 , and m82 in order to study the cold interstellar gas in dwarf starbursts . interstellar neutral sodium column densities were obtained by measuring the equivalent width of the na d absorption doublet . we find that out of the ...	we have obtained high resolution echelle spectra ( r = 30,000 - 50,000 ) of the na d absorption doublet ( , 5896 ) for six dwarf starburst galaxies and two more luminous starbursts : m82 and ngc 1614 . this is small compared to the highest velocity components in ngc 1614 and m82 ( blueshifted by 150 km s and 91 km s , ...	we have obtained high resolution echelle spectra ( r = 30,000 - 50,000 ) of the na d absorption doublet ( , 5896 ) for six dwarf starburst galaxies and two more luminous starbursts : m82 and ngc 1614 . the absorption features were separated into multiple components and separated into stellar and interstellar parts base...
cond-mat0002379	i	density and concentration fluctuations in fluids and fluid mixtures can be investigated experimentally by light - scattering techniques . the nature of these fluctuations when the system is in equilibrium is a subject well understood@xcite . here we shall consider fluctuations in nonequilibrium steady states ( ness ) ,...	we have performed light - scattering measurements in dilute and semidilute polymer solutions of polystyrene in toluene when subjected to stationary temperature gradients . the experiments confirm the presence of long - range nonequilibrium concentration fluctuations which are proportional to , where is the applied temp...	we have performed light - scattering measurements in dilute and semidilute polymer solutions of polystyrene in toluene when subjected to stationary temperature gradients . five solutions with concentrations below and one solution with a concentration above the overlap concentration were investigated . the experiments c...
cond-mat9808069	i	two - dimensional electronic systems , as found in single heterojunction interfaces or in more complex structures such as quantum wells , have been studied intensively because of their fundamental interest and for their potential application@xcite . in particular , the two - dimensional electron gas ( 2deg ) with a spa...	we have studied the collective plasma excitations of a two - dimensional electron gas with an _ arbitrary _ lateral charge - density modulation . the dynamics is formulated using a previously developed hydrodynamic theory based on the thomas - fermi - dirac - von weizscker approximation . in this approach , both the eq...	we have studied the collective plasma excitations of a two - dimensional electron gas with an _ arbitrary _ lateral charge - density modulation . the dynamics is formulated using a previously developed hydrodynamic theory based on the thomas - fermi - dirac - von weizscker approximation . in this approach , both the eq...
1104.4494	i	ngc346 is presently the region of most intense star formation in the entire small magellanic cloud ( smc ) . it contains over 30 o type stars ( massey , parker & garmany 1989 ; evans et al . 2006 ) that ionise the n66 nebula , the largest hii region in the smc ( henize 1956 ) . the presence of these very young ( @xmath...	we show that there are at least two , almost equally numerous , young populations with distinct ages of respectively and myr . we provide for all of them accurate physical parameters . this result is consistent with measurements of the mass accretion rate in the 30 dor region and in the milky way and suggests that l...	we have studied the properties of the stellar populations in the field of the ngc346 cluster in the small magellanic cloud , using a novel self - consistent method that allows us to reliably identify pre - main sequence ( pms ) objects actively undergoing mass accretion , regardless of their age . the method does not r...
1104.4494	i	we have studied the properties of the stellar populations in the field of the ngc346 cluster in the smc as observed with the acs camera on board the hubble space telescope ( sabbi et al . to this aim , we have employed a novel , self - consistent method that allows us to reliably identify pms stars undergoing active ma...	we have studied the properties of the stellar populations in the field of the ngc346 cluster in the small magellanic cloud , using a novel self - consistent method that allows us to reliably identify pre - main sequence ( pms ) objects actively undergoing mass accretion , regardless of their age . the method does not r...	we have studied the properties of the stellar populations in the field of the ngc346 cluster in the small magellanic cloud , using a novel self - consistent method that allows us to reliably identify pre - main sequence ( pms ) objects actively undergoing mass accretion , regardless of their age . the method does not r...
astro-ph0404447	c	we have compiled a nearly complete list of bright rgb , hb , and agb stars for the globular cluster m5 reaching from the core of the cluster to @xmath130 from the center . we have used these samples to conduct a thorough comparison with theory in order to test stellar interior physics under the conditions prevalent in ...	we have tabulated lists of upper red giant , horizontal , and asymptotic giant branch ( rgb , hb , agb ) stars in the globular cluster m5 that are complete to over from the core for the rgb and agb samples , and for the hb sample . samples of hb and agb stars in populous clusters may provide a means of calibrating the ...	we have tabulated lists of upper red giant , horizontal , and asymptotic giant branch ( rgb , hb , agb ) stars in the globular cluster m5 that are complete to over from the core for the rgb and agb samples , and for the hb sample . the large samples give us the most precise value of to date for a single globular cluste...
astro-ph9902043	c	assuming the rotation curve of m33 is flat within @xmath32 , kormendy & mcclure ( 1993 ) calculate an upper limit of @xmath125 on the mass of the nucleus . lauer et al . ( 1998 ) calculate a lower limit by determining a core mass of @xmath126 . a better estimate of the mass in the starburst region should be possible fr...	the discovery of milky way - type dust ( with a strong 2175 bump ) internal to the m33 nucleus is different from previous work which has found smc - like dust ( no bump ) near starburst regions . the amount by which dust can be processed may be related to the mass and age of the starburst as well as the extent to wh...	we have thoroughly characterized the ultraviolet to near - infrared ( 0.15 - 2.2 ) spectral energy distribution ( sed ) of the central parsec of the m33 nucleus through new infrared photometry and optical / near - infrared spectroscopy , combined with ultraviolet / optical observations from the literature and the hst a...
astro-ph9902043	c	by fitting the uv to near - ir sed of the m33 nucleus with a starburst model which includes stars , gas , and dust , we find the m33 nucleus to be composed of a @xmath270 myr burst of star formation with a mass of @xmath2@xmath182 enshrouded by a shell of mw - type dust ( @xmath9 ) . this result is different from previ...	the sed shows evidence for a significant level of attenuation , which we model through a monte carlo radiative transfer code as a shell of clumpy milky way - type dust ( ) . our starburst models include the effects of this dust and can fit the sed if the nucleus was the site of a moderate ( at 10 myrs ) episode of coev...	we have thoroughly characterized the ultraviolet to near - infrared ( 0.15 - 2.2 ) spectral energy distribution ( sed ) of the central parsec of the m33 nucleus through new infrared photometry and optical / near - infrared spectroscopy , combined with ultraviolet / optical observations from the literature and the hst a...
astro-ph0010075	i	in 1987 , bothun et al . reported the serendipitous discovery of the extraordinarily large low surface brightness ( lsb ) galaxy now known as malin-1 . in spite of having a projected @xmath8-band central surface brightness of only 26.5 mag arcsec@xmath9 , malin-1 is the largest spiral galaxy known , with a disk scale ...	we have used the radio telescope to obtain new global data for 16 giant low surface brightness ( lsb ) galaxies . our targets have optical luminosities and disk scale lengths at the high end for spiral galaxies ( and kpc for=75 mpc ) , but they have diffuse stellar disks , with mean disk surface brightnesses magni...	we have used the radio telescope to obtain new global data for 16 giant low surface brightness ( lsb ) galaxies . our targets have optical luminosities and disk scale lengths at the high end for spiral galaxies ( and kpc for=75 mpc ) , but they have diffuse stellar disks , with mean disk surface brightnesses magni...
cond-mat0202370	m	the fact that the madelung energy of a random alloy described either by the effective medium model defined by the ss - dft - cpa method or by the supercell model in conjunction with the ss - lsgf method differ from each other , has neither consequences for the final result for the total energy of the random alloy nor e...	this allows us to determine the madelung potential energy of a random alloy in the single - site mean field approximation which makes the conventional single - site density - functional- theory coherent potential approximation ( ss - dft - cpa ) method practically identical to the supercell lsgf method with a single - ...	we have used the locally self - consistent green s function ( lsgf ) method in supercell calculations to establish the distribution of the net charges assigned to the atomic spheres of the alloy components in metallic alloys with different compositions and degrees of order . this allows us to determine the madelung pot...
cond-mat0403517	i	low dimensional electron systems exhibit a rich variety of surprising effects which are due to the cooperative interplay of impurities and interactions . in one dimension even clean metallic systems are always strongly affected by interactions : at low energy scales physical properties obey anomalous power - laws , kno...	we improve the recently developed functional renormalization group ( frg ) for impurities and boundaries in luttinger liquids by including renormalization of the two - particle interaction , in addition to renormalization of the impurity potential . explicit flow equations are derived for spinless lattice fermions with...	we improve the recently developed functional renormalization group ( frg ) for impurities and boundaries in luttinger liquids by including renormalization of the two - particle interaction , in addition to renormalization of the impurity potential . explicit flow equations are derived for spinless lattice fermions with...
cond-mat0403517	c	in summary , we have shown that the frg provides an ideal tool for computing the intriguing properties of luttinger liquids with static impurities . the method yields ab initio results for microscopic model systems at all energy scales from the fermi energy to the ultimate low energy limit . we have demonstrated the ...	we compute spectral properties of single - particle excitations , and the oscillations in the density profile induced by impurities or boundaries for chains with up to lattice sites . a comparison with numerical density matrix renormalization results for systems with up to 1000 sites shows that the frg with the inclusi...	we improve the recently developed functional renormalization group ( frg ) for impurities and boundaries in luttinger liquids by including renormalization of the two - particle interaction , in addition to renormalization of the impurity potential . explicit flow equations are derived for spinless lattice fermions with...
1511.07313	i	a domain wall is a prototype collective excitation in a physical system , and it is also the paradigm example of a topological soliton @xcite . a domain wall can appear whenever there is a global symmetry that becomes spontaneously broken . it constitutes the boundary that separates two neighbouring domains , in which ...	we scrutinise collective many - atom motions during all - atom molecular dynamics simulations . the example we consider is an-helical subunit of the hiv envelope glycoprotein gp41 . but in isolation the helix becomes unstable , and the monomer starts deforming . we follow the process computationally . we interpret the ...	we inquire how structure emerges during the process of protein folding . for this we scrutinise collective many - atom motions during all - atom molecular dynamics simulations . we introduce , develop and employ various topological techniques , in combination with analytic tools that we deduce from the concept of integ...
1511.07313	i	molecular dynamics enables the scrutiny of protein folding , at the level of individual atoms and over very short time intervals . however , it can leave us with the conceptual challenge to understand , how the individual atoms cooperate to produce the kind of large scale organisation that appears to be prevalent among...	we inquire how structure emerges during the process of protein folding . for this we introduce , develop and employ various topological techniques , in combination with analytic tools that we deduce from the concept of integrable models and structure of discrete nonlinear schrdinger equation . the helical structure is ...	we inquire how structure emerges during the process of protein folding . for this we scrutinise collective many - atom motions during all - atom molecular dynamics simulations . we introduce , develop and employ various topological techniques , in combination with analytic tools that we deduce from the concept of integ...
math0205030	i	the problem of the existence of periodic orbits for hamiltonian systems has a very far and rich history in the development of mathematics and physics . in fact , some of the major contributions on this question include the celebrated poincar - birkhoff theorem on the existence of periodic orbits for area preserving twi...	we introduce the hofer - zehnder-semicapacity of a symplectic manifold ( or-sensitive hofer - zehnder capacity ) with respect to a subgroup ( ) and prove that given a geometrically bounded symplectic manifold and an open subset admitting a hamiltonian free circle action with order greater than two then has bounded hofe...	we introduce the hofer - zehnder-semicapacity of a symplectic manifold ( or-sensitive hofer - zehnder capacity ) with respect to a subgroup ( ) and prove that given a geometrically bounded symplectic manifold and an open subset admitting a hamiltonian free circle action with order greater than two then has bounded hofe...
nucl-th0402026	i	the phase transition from partonic degrees of freedom ( quarks and gluons ) to interacting hadrons is a central topic of modern high - energy physics @xcite . in order to understand the dynamics and relevant scales of this transition laboratory experiments under controlled conditions are presently performed with ultra ...	we investigate hadron production as well as transverse hadron spectra from proton - proton , proton - nucleus and nucleus - nucleus collisions from 2gev to 21.3tev within two independent transport approaches ( hsd and urqmd ) that are based on quark , diquark , string and hadronic degrees of freedom . we investigate va...	we investigate hadron production as well as transverse hadron spectra from proton - proton , proton - nucleus and nucleus - nucleus collisions from 2gev to 21.3tev within two independent transport approaches ( hsd and urqmd ) that are based on quark , diquark , string and hadronic degrees of freedom . the comparison to...