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2022-08-05 | Quadratic Symmetric Polynomials and an analogue of the Davenport Constant | In this paper, we define the constant $D(\varphi, p)$, an analogue for the
Davenport constant, for sequences on the finite field $\mathbb{F}_p$, defined
via quadratic symmetric polynomials. Next, we state a series of results
presenting either the exact value of $D(\varphi, p)$, or lower and upper bounds
for this consta... | 2208.03212v1 |
2022-08-15 | Liouville Theorem on Ricci shrinkers with constant scalar curvature and its application | In this paper we consider harmonic functions on gradient shrinking Ricci
solitons with constant scalar curvature. A Liouville theorem is proved without
using gradient estimate : any bounded harmonic function is constant on gradient
shrinking Ricci solitons with constant scalar curvature. As an application, we
show that... | 2208.07101v1 |
2022-10-24 | Isoparametric hypersurfaces and hypersurfaces with constant principal curvatures in Finsler spaces | In this paper, we study the relationship between isoparametric hypersurfaces
and hypersurfaces
with constant principal curvatures in Finsler spaces. We give some examples
of isoparametric hypersurfaces with (non)constant principal curvatures on
Randers manifolds with nonconstant flag curvatures. Furthermore, we const... | 2210.12937v1 |
2022-11-21 | A Cut-Matching Game for Constant-Hop Expanders | This paper provides a cut-strategy that produces constant-hop expanders in
the well-known cut-matching game framework.
Constant-hop expanders strengthen expanders with constant conductance by
guaranteeing that any demand can be (obliviously) routed along constant-hop
paths - in contrast to the $\Omega(\log n)$-hop ro... | 2211.11726v1 |
2023-03-14 | Some fast convergent series for the mathematical constants $ζ(4)$ and $ζ(5)$ | Recently, Sun [preprint, arXiv: 2210.07238v7] proposed two conjectural series
for the mathematical constant $\zeta(4)$ and two conjectural series for the
mathematical constant $\zeta(5)$. In terms of the operator method and two
hypergeometric transformations, we prove these four conjectures. Furthermore,
we also find s... | 2303.07887v2 |
2023-05-26 | Geodesics on metrics of Eguchi-Hanson type | Geodesic equations are solved when at least two of $\theta$, $\phi$ and
$\psi$ are constant, or $r$ is constant, on scalar flat metrics of
Eguchi-Hanson type. They can also be solved also on Eguchi-Hanson metrics which
are Ricci flat if only $\phi$ is constant. However, the explicit solution of
the geodesic equations i... | 2305.18621v1 |
1996-10-28 | QSO Absorbing Galaxies at z<~1: Deep Imaging and Spectroscopy in the Field of 3C 336 | We present very deep WFPC2 images and FOS spectroscopy from the Hubble Space
Telescope (HST) together with numerous supporting ground-based observations of
the field of the quasar 3C 336 ($z_{em}=0.927$). The observations are designed
to investigate the nature of galaxies producing metal line absorption systems
in the ... | 9610230v1 |
1996-11-05 | The nature of intermediate-redshift damped Ly-alpha absorbers | We present HST/WFPC2 high-spatial resolution images in the R and B bands of
the close environment of the sightlines to seven quasars which spectra show
either a damped Ly-alpha absorption line, 21cm absorption, or a very strong
MgII/FeII absorption system at intermediate redshifts (0.4 < z < 1). Objects
down to about 0... | 9611031v1 |
1997-07-08 | The Formation of Galactic Disks | We study the population of galactic disks expected in current hierarchical
clustering models for structure formation. A rotationally supported disk with
exponential surface density profile is assumed to form with a mass and angular
momentum which are fixed fractions of those of its surrounding dark halo. We
assume that... | 9707093v1 |
1997-09-26 | No C+ emission from the z=3.137 damped Lyman-alpha absorber towards PC1643+4631A | We describe a search for redshifted [C II] in a z=3.137 damped Ly-alpha
absorption system that has a large neutral hydrogen column density and which
was controversially reported to be a source of CO emission, indicative of rapid
star-formation (Frayer, Brown & Vanden Bout 1994; Braine, Downes & Guilloteau
1996). There ... | 9709266v1 |
1998-04-06 | Three-dimensional waves generated at Lindblad resonances in thermally stratified disks | We analyze the linear, 3D response to tidal forcing of a disk that is thin
and thermally stratified in the direction normal to the disk plane. We model
the vertical disk structure locally as a polytrope which represents a disk of
high optical depth. We solve the 3D gas-dynamic equations semi-analytically in
the neighbo... | 9804063v1 |
2000-11-23 | Near-Infrared Integral Field Spectroscopy of Damped Lyman-alpha Systems | We assess the feasibility of detecting star formation in damped Lyman-alpha
systems (DLAs) at z>1 through near-infrared spectroscopy using the forthcoming
integral field units on 8m-class telescopes. Although their relation to
galaxies is not well established, high-z DLAs contain most of the neutral gas
in the Universe... | 0011421v1 |
2001-12-03 | Euler, Jacobi, and Missions to Comets and Asteroids | Whenever a freely spinning body is found in a complex rotational state, this
means that either the body is a recent victim of an impact or a tidal
interaction, or is a fragment of a recently disrupted progenitor. Another
factor (relevant for comets) is outgassing. Due to impacts, tidal forces and
outgassing, the astero... | 0112054v3 |
2002-06-17 | The UCSD HIRES/KECK I Damped Lya Abundance Database: IV. Probing Galactic Enrichment Histories with Nitrogen | We present 14 N^0 measurements from our HIRES/Keck database of damped Lya
abundances. These data are combined with measurements from the recent and past
literature to build an homogeneous, uniform set of observations. We examine
photoionization diagnostics like Fe^++ and Ar^0 in the majority of the complete
sample and ... | 0206296v1 |
2003-08-11 | The Nature of Damped Ly-alpha Absorbing Galaxies at z<=1--A Photometric Redshift Survey of Damped Ly-alpha Absorbers | We study the nature of damped Lya absorption (DLA) systems at z<=1 using a
sample of 11 DLA galaxies, for which accurate redshift measurements are
available. We demonstrate that the precision of photometric redshifts is
sufficient for identifying DLA galaxies, because DLAs are rare and their
intrinsically high column d... | 0308190v1 |
2004-07-21 | Discovery of a Primitive Damped Lyman alpha Absorber Near an X-ray Bright Galaxy Group in the Virgo Cluster | We present a new UV echelle spectrum of PG1216+069, obtained with HST+STIS,
which reveals damped Lya (DLA) absorption as well as O I, C II, Si II, and Fe
II absorption lines at z(abs) = 0.00632 near the NGC4261 group. The absorber
shows no evidence of highly-ionized gas, which places constraints on "warm-hot"
missing b... | 0407465v2 |
2004-08-27 | Detection of 21 Centimeter HI Absorption at z = 0.78 in a Survey of Radio Continuum Sources | We report the detection of a deep broad HI 21 cm absorption system at z =
0.78 toward the radio source [HB89] 2351+456 (4C+45.51) at z = 1.992. The HI
absorption was identified in a blind spectral line survey conducted at the
Green Bank Telescope spanning 0.63 < z < 1.10 toward a large sample of radio
continuum sources... | 0408531v1 |
2005-03-17 | The first WIMPy halos | Dark matter direct and indirect detection signals depend crucially on the
dark matter distribution. While the formation of large scale structure is
independent of the nature of the cold dark matter (CDM), the fate of
inhomogeneities on sub-galactic scales, and hence the present day CDM
distribution on these scales, dep... | 0503387v2 |
2005-06-30 | Molecular Hydrogen in the Damped Ly alpha Absorber of Q1331+170 | We used HST/STIS to obtain the spectrum of molecular hydrogen associated with
the damped Ly$\alpha$ system at $z_{\rm abs}=1.7765$ toward the quasar
Q1331+170 at $z_{\rm em}=2.084$. Strong ${\rm H}_2$ absorption was detected,
with a total ${\rm H}_2$ column density of $N({\rm H}_2)=(4.45\pm 0.36)\times
10^{19} {\rm cm^... | 0506766v1 |
1997-05-06 | Resonant Raman Scattering in Antiferromagnets | Two-magnon Raman scattering provides important information about electronic
correlations in the insulating parent compounds of high-$T_c$ materials. Recent
experiments have shown a strong dependence of the Raman signal in $B_{1g}$
geometry on the frequency of the incoming photon. We present an analytical and
numerical ... | 9705051v1 |
1998-09-15 | Solid friction at high sliding velocities: an explicit 3D dynamical SPH approach | We present realistic 3D numerical simulations of elastic bodies sliding on
top of each other in a regime of velocities ranging from meters to tens of
meters per second using the so-called Smoothed Particle Hydrodynamics (SPH)
method. Our investigations are restricted to regimes of pressure and roughness
where only elas... | 9809213v1 |
2000-03-10 | Competing orders and quantum criticality in doped antiferromagnets | We use a number of large-N limits to explore the competition between ground
states of square lattice doped antiferromagnets which break electromagnetic
U(1), time-reversal, or square lattice space group symmetries. Among the states
we find are d-, (s+id)-, and (d+id)-wave superconductors, Wigner crystals,
Wigner crysta... | 0003163v7 |
2001-12-03 | Theory of proximity effect in superconductor/ferromagnet heterostructures | We present a microscopic theory of proximity effect in the
ferromagnet/superconductor/ferromagnet (F/S/F) nanostructures where S is s-wave
low-T_c superconductor and F's are layers of 3d transition ferromagnetic metal.
Our approach is based on the solution of Gor'kov equations for the normal and
anomalous Green's funct... | 0112034v3 |
2007-07-27 | C IV absorption in damped and sub-damped Lyman-alpha systems: correlations with metallicity and implications for galactic winds at z~2-3 | We present a study of C IV absorption in a sample of 63 damped Lyman-alpha
(DLA) systems and 11 sub-DLAs in the redshift range 1.75<z_abs<3.61, using a
dataset of high-resolution (6.6 km/s FWHM), high signal-to-noise VLT/UVES
spectra. Narrow and broad C IV absorption line components indicate the presence
of both warm, ... | 0707.4065v2 |
2008-10-01 | Corotational Instability of Inertial-Acoustic Modes in Black Hole Accretion Discs and Quasi-Periodic Oscillations | We study the global stability of non-axisymmetric p-modes (also called
inertial-acoustic modes) trapped in the inner-most regions of accretion discs
around black holes. We show that the lowest-order (highest-frequency) p-modes,
with frequencies $\omega=(0.5-0.7) m\Omega_{\rm ISCO}$, can be overstable due
to general rel... | 0810.0203v2 |
2008-10-03 | Stochastic excitation of nonradial modes II. Are solar asymptotic gravity modes detectable? | Detection of solar gravity modes remains a major challenge to our
understanding of the innerparts of the Sun. Their frequencies would enable the
derivation of constraints on the core physical properties while their
amplitudes can put severe constraints on the properties of the inner convective
region. Our purpose is to... | 0810.0602v2 |
2008-10-20 | The kinematic signature of damped Lyman alpha systems: Using the D-index to screen for high column density HI absorbers | Using a sample of 21 damped Lyman alpha systems (DLAs) and 35 sub-DLAs, we
evaluate the D-index = EW / Delta v x 1000 from high resolution spectra of the
MgII lambda 2796 profile. This sample represents an increase in sub-DLA D-index
statistics by a factor of four over the sample used by Ellison (2006). We
investigate ... | 0810.3700v1 |
2009-01-24 | Dynamic migration of rotating neutron stars due to a phase transition instability | Using numerical simulations based on solving the general relativistic
hydrodynamic equations, we study the dynamics of a phase transition in the
dense core of isolated rotating neutron stars, triggered by the back bending
instability reached via angular momentum loss. In particular, we investigate
the dynamics of a mig... | 0901.3819v2 |
2009-02-12 | New Magellan Inamori Kyocera Echelle Observations of z<1.5 sub-damped Lyman-alpha systems | The Damped and sub-Damped Lyman-alpha (DLA and sub-DLA) systems seen in the
spectra of QSOs offer a unique way to study the interstellar medium of high
redshift galaxies. In this paper we report on new abundance determinations in a
sample of 10 new systems, nine of the lesser studied sub-DLAs and one DLA,
along the lin... | 0902.2022v2 |
2009-04-16 | Revisiting the origin of the high metallicities of sub-damped Lyman-alpha systems | Sub-damped Lyman-alpha systems (sub-DLAs) have previously been found to
exhibit a steeper metallicity evolution than the classical damped Lyman-alpha
systems (DLAs), evolving to close to solar metallicity by z~1. From new
high-resolution spectra of 17 sub-DLAs we have increased the number of
measurements of [Fe/H] at z... | 0904.2531v1 |
2009-05-27 | A MIKE + UVES survey of Sub-Damped Lyman-Alpha Systems at z<1.5 | We have combined the results from our recent observations of Damped and
sub-Damped Lyman-alpha systems with the MIKE and UVES spectrographs on the
Magellan Clay and VLT Kueyen telescopes with ones from the literature to
determine the N(HI)-weighted mean metallicity of these systems based both on
Fe, a depleted element ... | 0905.4473v2 |
2009-12-14 | Using 21cm Absorption in Small Impact Parameter Galaxy-QSO Pairs to Probe Low-Redshift Damped and Sub-Damped Lyman-alpha System | To search for low-redshift damped Lyman-alpha (DLA) and sub-DLA quasar
absorbers, we have conducted a 21cm absorption survey of radio-loud quasars at
small impact parameters to foreground galaxies selected from the Sloan Digital
Sky Survey (SDSS). Here we present the first results from this survey based on
observations... | 0912.2575v2 |
2010-04-21 | Kadanoff-Baym description of Hubbard clusters out of equilibrium: performance of many-body schemes, correlation-induced damping and multiple steady states | We present in detail a method we recently introduced (PRL. 103, 176404
(2009)) to describe finite systems in and out of equilibrium, where the
evolution in time is performed via the Kadanoff-Baym Equations (KBE) within
Many-Body Perturbation Theory (MBPT). The main property we analyze is the
time-dependent density. We ... | 1004.3662v1 |
2010-05-22 | Helical edge magnetoplasmon in the quantum Hall effect regime | We present the microscopic treatment of edge magnetoplasmons (EMPs) for the
regime of not-too-low temperatures defined by the condition $\hbar
\omega_{c}\gg k_{B}T\gg \hbar v_{g}/2\ell_{0}$, where $v_{g}$ is the group
velocity of the edge states, $\ell_{0}=\sqrt{\hbar /m^{\ast}\omega_{c}}$ is the
magnetic length and $\... | 1005.4154v1 |
2010-06-02 | Do Damped and Sub-damped Lyman-alpha Absorbers Arise in Galaxies of Different Masses? | We consider the questions of whether the damped Lyman-alpha (DLA) and sub-DLA
absorbers in quasar spectra differ intrinsically in metallicity, and whether
they could arise in galaxies of different masses. Using the recent measurements
of the robust metallicity indicators Zn and S in DLAs and sub-DLAs, we confirm
that s... | 1006.0298v1 |
2010-08-31 | A SINFONI Integral Field Spectroscopy Survey for Galaxy Counterparts to Damped Lyman-alpha Systems - I. New Detections and Limits for Intervening and Associated Absorbers | Detailed studies of Damped and sub-Damped Lyman-alpha systems (DLA), the
galaxies probed by the absorption they produce in the spectra of background
quasars, rely on identifying the galaxy responsible for the absorber with more
traditional methods. Integral field spectroscopy provides an efficient way of
detecting fain... | 1009.0025v1 |
2010-12-22 | Abstract Wave Equations and Associated Dirac-Type Operators | We discuss the unitary equivalence of generators $G_{A,R}$ associated with
abstract damped wave equations of the type $\ddot{u} + R \dot{u} + A^*A u = 0$
in some Hilbert space $\mathcal{H}_1$ and certain non-self-adjoint Dirac-type
operators $Q_{A,R}$ (away from the nullspace of the latter) in $\mathcal{H}_1
\oplus \ma... | 1012.4927v2 |
2011-02-18 | The First Observations of Low Redshift Damped Lyman-alpha Systems with the Cosmic Origins Spectrograph | We report on the first Cosmic Origins Spectrograph (COS) observations of
damped and sub-damped Lyman-alpha (DLA) systems discovered in a new survey of
the gaseous halos of low-redshift galaxies. From observations of 37 sightlines,
we have discovered three DLAs and four sub-DLAs. We measure the neutral gas
density Omega... | 1102.3927v1 |
2011-05-23 | BCS - BEC crossover and quantum hydrodynamics in p-wave superfluids with a symmetry of the A1 - phase | We solve the Leggett equations for the BCS - BEC crossover in the three
dimension resonance p-wave superfluid with the symmetry of the A1 - phase. We
calculate the sound velocity, the normal density, and the specific heat for the
BCS-domain (\mu > 0), BEC-domain (\mu < 0), and close to important point \mu =
0 in 100% p... | 1105.4438v1 |
2011-07-12 | Considerations on the accretion of Uranus and Neptune by mutual collisions of planetary embryos in the vicinity of Jupiter and Saturn | Modeling the formation of the ice giants Uranus and Neptune is a long-lasting
problem in planetary science. Due to gas-drag, collisional damping, and
resonant shepherding, the planetary embryos repel the planetesimals away from
their reach and thus they stop growing (Levison et al. 2010). This problem
persists independ... | 1107.2235v2 |
2011-08-19 | The ALFALFA HI Absorption Pilot Survey: A Wide-Area Blind Damped Lyman Alpha System Survey of the Local Universe | We present the results of a pilot survey for neutral hydrogen (HI) 21 cm
absorption in the Arecibo Legacy Fast Arecibo L-Band Feed Array (ALFALFA)
Survey. This project is a wide-area "blind" search for HI absorption in the
local universe, spanning -650 km/s < cz < 17,500 km/s and covering 517.0 square
degrees (7% of th... | 1108.4011v1 |
2011-09-22 | Tidal Dissipation in Planet-Hosting Stars: Damping of Spin-Orbit Misalignment and Survival of Hot Jupiters | Observations of hot Jupiters around solar-type stars with very short orbital
periods (~day) suggest that tidal dissipation in such stars is not too
efficient so that these planets can survive against rapid orbital decay. This
is consistent with recent theoretical works, which indicate that the tidal Q of
planet-hosting... | 1109.4703v2 |
2011-10-20 | The First Observations of Low-Redshift Damped Lyman-α Systems with the Cosmic Origins Spectrograph: Chemical Abundances and Affiliated Galaxies | We present Cosmic Origins Spectrograph (COS) measurements of metal abundances
in eight 0.083<z<0.321 damped Lyman-\alpha (DLA) and sub-damped Ly-\alpha\
absorption systems serendipitously discovered in the COS-Halos survey. We find
that these systems show a large range in metallicities, with -1.10<[Z/H]<0.31,
similar t... | 1110.4557v2 |
2011-11-01 | On the misalignment of the directly imaged planet β Pictoris b with the system's warped inner disk | The vertical warp in the debris disk Beta Pictoris -- an inclined inner disk
extending into a flat outer disk -- has long been interpreted as the signpost
of a planet on an inclined orbit. Direct images spanning 2004-2010 have
revealed Beta Pictoris b, a planet with a mass and orbital distance consistent
with this pict... | 1111.0297v2 |
2011-11-25 | Application of a damped Locally Optimized Combination of Images method to the spectral characterization of faint companions using an Integral Field Spectrograph | High-contrast imaging instruments are now being equipped with integral field
spectrographs (IFS) to facilitate the detection and characterization of faint
substellar companions. Algorithms currently envisioned to handle IFS data, such
as the Locally Optimized Combination of Images (LOCI) algorithm, rely upon
aggressive... | 1111.6102v1 |
2012-02-01 | CMB at 2x2 order: the dissipation of primordial acoustic waves and the observable part of the associated energy release | Silk damping of primordial small-scale perturbations in the photon-baryon
fluid due to diffusion of photons inevitably creates spectral distortions in
the CMB. With the proposed CMB experiment PIXIE it might become possible to
measure these distortions and thereby constrain the primordial power spectrum
at comoving wav... | 1202.0057v2 |
2012-02-28 | The Last Stages of Terrestrial Planet Formation: Dynamical Friction and the Late Veneer | The final stage of terrestrial planet formation consists of the cleanup of
residual planetesimals after the giant impact phase. Dynamically, a residual
planetesimal population is needed to damp the high eccentricities of the
terrestrial planets after the giant impact stage. Geochemically, highly
siderophile element (HS... | 1202.6372v2 |
2012-03-13 | Trapping in three-planet resonances during gas-driven migration | We study the establishment of three-planet resonances -similar to the Laplace
resonance in the Galilean satellites- and their effects on the mutual
inclinations of the orbital planes of the planets, assuming that the latter
undergo migration in a gaseous disc. In particular, we examine the resonance
relations that occu... | 1203.2960v1 |
2012-10-04 | Plasmonic Waves on a Chain of Metallic Nanoparticles: Effects of a Liquid Crystalline Host or an Applied Magnetic Field | A chain of metallic particles, of sufficiently small diameter and spacing,
allows linearly polarized plasmonic waves to propagate along the chain. In this
paper, we consider how these waves are altered by an anisotropic host (such as
a nematic liquid crystal) or an applied magnetic field. In a liquid crystalline
host, ... | 1210.1509v1 |
2012-11-12 | The explosion energy of early stellar populations: The Fe-peak element ratios in low metallicity damped Lyman-alpha systems | The relative abundances of the Fe-peak elements (Ti-Zn) at the lowest
metallicities are intimately linked to the physics of core-collapse supernova
explosions. With a sample of 25 very metal-poor damped Lyman-alpha systems, we
investigate the trends of the Fe-peak element ratios with metallicity. For nine
of the 25 DLA... | 1211.2805v3 |
2012-12-07 | Circumstellar disks can erase the effects of stellar fly-bys on planetary systems | Most stars form in embedded clusters. Stellar flybys may affect the orbital
architecture of the systems by exciting the eccentricity and causing dynamical
instability. Since, incidentally, the timescale over which a cluster loses its
gaseous component and begins to disperse is comparable to the circumstellar
disk lifet... | 1212.1561v1 |
2013-01-22 | Effect of partial ionization on wave propagation in solar magnetic flux tubes | Observations show that waves are ubiquitous in the solar atmosphere and may
play an important role for plasma heating. The study of waves in the solar
corona is usually based on linear ideal magnetohydrodynamics (MHD) for a fully
ionized plasma. However, the plasma in the photosphere and the chromosphere is
only partia... | 1301.5214v1 |
2013-02-07 | Secular Orbital Evolution of Compact Planet Systems | Recent observations have shown that at least some close-in exoplanets
maintain eccentric orbits despite tidal circularization timescales that are
typically shorter than stellar ages. We explore gravitational interactions with
a distant planetary companion as a possible cause of these non-zero
eccentricities. For simpli... | 1302.1620v2 |
2013-05-10 | Nonlinear Development of the R Mode Instability and the Maximum Rotation Rate of Neutron Stars | We describe how the nonlinear development of the R mode instability of
neutron stars influences spin up to millisecond periods via accretion. Our
arguments are based on nearly-resonant interactions of the R mode with pairs of
"daughter modes". The amplitude of the R mode saturates at the lowest value for
which parametr... | 1305.2335v2 |
2013-07-28 | Constraint damping of the conformal and covariant formulation of the Z4 system in simulations of binary neutron stars | Following previous work in vacuum spacetimes, we investigate the
constraint-damping properties in the presence of matter of the recently
developed traceless, conformal and covariant Z4 (CCZ4) formulation of the
Einstein equations. First, we evolve an isolated neutron star with an ideal gas
equation of state and subject... | 1307.7391v2 |
2013-08-05 | Peculiar Velocity Decomposition, Redshift Space Distortion and Velocity Reconstruction in Redshift Surveys. II. Dark Matter Velocity Statistics | Massive spectroscopic redshift surveys open a promising window to accurately
measure peculiar velocity at cosmological distances through redshift space
distortion (RSD). In paper I of this series of work we proposed to decompose
peculiar velocity into three eigen-modes (v_\delta, v_S and v_B) in order to
facilitate the... | 1308.0886v4 |
2013-10-25 | A SINFONI Integral Field Spectroscopy Survey for Galaxy Counterparts to Damped Lyman-alpha Systems - V. Neutral and Ionised Phase Metallicities | The gas-phase and stellar metallicities have proven to be important
parameters to constrain the star formation history of galaxies. However, HII
regions associated with recent star-formation may not have abundances typical
for the galaxy as a whole and it is believed that the bulk of the metals may be
contained in the ... | 1310.6865v1 |
2014-04-10 | Thirty-six New, High-Probability, Damped Ly-alpha Absorbers at Redshift 0.42 < z < 0.70 | Quasar damped Ly-alpha (DLA) absorption line systems with redshifts z<1.65
are used to trace neutral gas over approximately 70 per cent of the most recent
history of the Universe. However, such systems fall in the UV and are rarely
found in blind UV spectroscopic surveys. Therefore, it has been difficult to
compile a m... | 1404.2914v2 |
2014-05-03 | 3D MHD simulation of linearly polarised Alfven wave dynamics in Arnold-Beltrami-Childress magnetic field | Previous studies [Malara et al ApJ, 533, 523 (2000)] considered
small-amplitude Alfven wave (AW) packets in Arnold-Beltrami-Childress (ABC)
magnetic field using WKB approximation. In this work linearly polarised Alfven
wave dynamics in ABC magnetic field via direct 3D MHD numerical simulation is
studied for the first t... | 1405.0587v1 |
2014-11-25 | Investigation of toroidal acceleration and potential acceleration forces in EAST and J-TEXT plasmas | In order to produce intrinsic rotation, bulk plasmas must be collectively
accelerated by the net force exerted on them, which results from both driving
and damping forces. So, to study the possible mechanisms of intrinsic rotation
generation, it is only needed to understand characteristics of driving and
damping terms ... | 1411.6744v1 |
2015-01-07 | Understanding resonance graphs using Easy Java Simulations (EJS) and why we use EJS | This paper reports a computer model- simulation created using Easy Java
Simulation (EJS) for learners to visualize how the steady-state amplitude of a
driven oscillating system varies with the frequency of the periodic driving
force. The simulation shows (N=100) identical spring-mass systems being
subjected to (1) peri... | 1501.01535v4 |
2015-04-20 | Forward Modeling of Reduced Power Spectra From Three-Dimensional k-Space | We present results from a numerical forward model to evaluate one-dimensional
reduced power spectral densities (PSD) from arbitrary energy distributions in
$\mathbf{k}$-space. In this model, we can separately calculate the diagonal
elements of the spectral tensor for incompressible axisymmetric turbulence with
vanishin... | 1504.04995v2 |
2015-07-13 | The role of low-energy phonons with mean-free-paths >0.8 um in heat conduction in silicon | Despite recent progress in the first-principles calculations and measurements
of phonon mean-free-paths (MFPs), contribution of low-energy phonons to heat
conduction in silicon is still inconclusive, as exemplified by the
discrepancies between different first-principles calculations. Here we
investigate the contributio... | 1507.03422v4 |
2015-08-27 | Nonlinear Landau damping and modulation of electrostatic waves in a nonextensive electron-positron-pair plasma | The nonlinear theory of amplitude modulation of electrostatic wave envelopes
in a collisionless electron-positron (EP) pair plasma is studied by using a set
of Vlasov-Poisson equations in the context of Tsallis' $q$-nonextensive
statistics. In particular, the previous linear theory of Langmuir oscillations
in EP plasma... | 1508.06903v2 |
2015-10-03 | Systematic investigations of deep sub-barrier fusion reactions using an adiabatic approach | To describe fusion hindrance observed in fusion reactions at extremely low
incident energies, I propose a novel extension of the standard CC model by
introducing a damping factor that describes a smooth transition from sudden to
adiabatic processes. I demonstrate the performance of this model by
systematically investig... | 1510.00806v1 |
2015-10-29 | Numerical simulations of transverse oscillations in radiatively cooling coronal loops | We aim to study the influence of radiative cooling on the standing kink
oscillations of a coronal loop. Using the FLASH code, we solved the 3D ideal
magnetohydrodynamic equations. Our model consists of a straight, density
enhanced and gravitationally stratified magnetic flux tube. We perturbed the
system initially, lea... | 1510.08760v1 |
2016-04-28 | Single-Particle Dynamics in a Nonlinear Accelerator Lattice: Attaining a Large Tune Spread with Octupoles in IOTA | Fermilab is constructing the Integrable Optics Test Accelerator (IOTA) as the
centerpiece of the Accelerator R&D Program towards high-intensity circular
machines. One of the factors limiting the beam intensity in present circular
accelerators is collective instabilities, which can be suppressed by a spread
of betatron ... | 1604.08565v4 |
2016-10-12 | Dipole modes with depressed amplitudes in red giants are mixed modes | Seismic observations have shown that a number of evolved stars exhibit
low-amplitude dipole modes, which are referred to as depressed modes. Recently,
these low amplitudes have been attributed to the presence of a strong magnetic
field in the stellar core of those stars.
We intend to study the properties of depressed... | 1610.03872v1 |
2016-11-07 | Three-phonon and four-phonon interaction processes in a pair-condensed Fermi gas | We study the interactions among phonons and the phonon lifetime in a
pair-condensed Fermi gas in the BEC-BCS crossover in the collisionless regime.
To compute the phonon-phonon coupling amplitudes we use a microscopic model
based on a generalized BCS Ansatz including moving pairs, which allows for a
systematic expansio... | 1611.01954v3 |
2016-11-20 | Migration of Planets Into and Out of Mean Motion Resonances in Protoplanetary Disks: Analytical Theory of Second-Order Resonances | Recent observations of Kepler multi-planet systems have revealed a number of
systems with planets very close to second-order mean motion resonances (MMRs,
with period ratio $1:3$, $3:5$, etc.) We present an analytic study of resonance
capture and its stability for planets migrating in gaseous disks. Resonance
capture r... | 1611.06463v2 |
2016-11-29 | Kinetic Field Theory: Effects of momentum correlations on the cosmic density-fluctuation power spectrum | In earlier work, we have developed a Kinetic Field Theory (KFT) for
cosmological structure formation and showed that the non-linear
density-fluctuation power spectrum known from numerical simulations can be
reproduced quite well even if particle interactions are taken into account to
first order only. Besides approxima... | 1611.09503v2 |
2016-12-08 | Highly inclined and eccentric massive planets. II. Planet-planet interactions during the disc phase | We aim to investigate the influence of the eccentricity and inclination
damping due to planet-disc interactions on the final configurations of the
systems, generalizing previous studies on the combined action of the gas disc
and planet-planet scattering during the disc phase. Instead of the simplistic
$K$-prescription,... | 1612.02693v1 |
2017-02-22 | A Model of Energetic Ion Effects on Pressure Driven Tearing Modes in Tokamaks | The effects that energetic trapped ions have on linear resistive
magnetohydrodynamic (MHD) instabilities are studied in a reduced model that
captures the essential physics driving or damping the modes through variations
in the magnetic shear. The drift-kinetic orbital interaction of a slowing down
distribution of trapp... | 1702.06837v2 |
2017-07-31 | Investigating quantum wireless multihop teleportation under decoherence | This research work scrutinizes quantum routing protocol with multihop
teleportation for wireless mesh backbone networks, in amplitude and phase
damping channels. After analyzing the quantum multihop protocol, we select a
four-qubit cluster state as the quantum channel for the protocol. The quantum
channel linking the i... | 1708.00087v6 |
2017-11-30 | Origins of sharp cosmic-ray electron structures and the DAMPE excess | Nearby sources may contribute to cosmic-ray electron (CRE) structures at high
energies. Recently, the first DAMPE results on the CRE flux hinted at a narrow
excess at energy ~1.4 TeV. We show that in general a spectral structure with a
narrow width appears in two scenarios: I) "Spectrum broadening" for the
continuous s... | 1712.00005v2 |
2017-11-30 | Bayesian analysis of the break in DAMPE lepton spectra | Recently, DAMPE has released its first results on the high-energy cosmic-ray
electrons and positrons (CREs) from about $25$ GeV to $4.6$ TeV, which directly
detect a break at $\sim 1$ TeV. This result gives us an excellent opportunity
to study the source of the CREs excess. In this work, we used the data fo
proton and ... | 1712.00372v4 |
2017-12-07 | Internal alignment and position resolution of the silicon tracker of DAMPE determined with orbit data | The DArk Matter Particle Explorer (DAMPE) is a space-borne particle detector
designed to probe electrons and gamma-rays in the few GeV to 10 TeV energy
range, as well as cosmic-ray proton and nuclei components between 10 GeV and
100 TeV. The silicon-tungsten tracker-converter is a crucial component of
DAMPE. It allows ... | 1712.02739v2 |
2018-01-24 | Modelling redshift-space distortion in the post-reionization ${\rm HI}$ 21-cm power spectrum | The post-reionization ${\rm HI}$ 21-cm signal is an excellent candidate for
precision cosmology, this however requires accurate modelling of the expected
signal. Sarkar et al. (2016) have simulated the real space ${\rm HI}$ 21-cm
signal, and have modelled the ${\rm HI}$ power spectrum as $P_{{\rm HI}}(k)=b^2
P(k)$ wher... | 1801.07868v1 |
2018-05-09 | Amplitude and lifetime of radial modes in red giant star spectra observed by Kepler | Context: the space-borne missions CoRoT and Kepler have provided photometric
observations of unprecedented quality. The study of solar-like oscillations
observed in red giant stars by these satellites allows a better understanding
of the different physical processes occurring in their interiors. In
particular, the stud... | 1805.03690v1 |
2018-05-31 | Impact of bias and redshift-space modelling for the halo power spectrum: Testing the effective field theory of large-scale structure | We study the impact of different bias and redshift-space models on the halo
power spectrum, quantifying their effect by comparing the fit to a subset of
realizations taken from the WizCOLA suite. These provide simulated power
spectrum measurements between $k_{\rm min}$ = 0.03 h/Mpc and $k_{\rm max}$ =
0.29 h/Mpc, const... | 1805.12394v3 |
2018-06-10 | Non-damping oscillations at flaring loops | Context. QPPs are usually detected as spatial displacements of coronal loops
in imaging observations or as periodic shifts of line properties in
spectroscopic observations. They are often applied for remote diagnostics of
magnetic fields and plasma properties on the Sun. Aims. We combine imaging and
spectroscopic measu... | 1806.03573v1 |
2018-09-05 | Nonlinear Mixed Modes in Red Giants | Turbulent motions in the convective envelope of red giants excite a rich
spectrum of solar-like oscillation modes. Observations by CoRoT and Kepler have
shown that the mode amplitudes increase dramatically as the stars ascend the
red giant branch, i.e., as the frequency of maximum power, $\nu_\mathrm{max}$,
decreases. ... | 1809.01727v2 |
2018-12-14 | Probing neutron star structure via f-mode oscillations and damping in dynamical spacetime models | Gravitational wave and electromagnetic observations can provide new insights
into the nature of matter at supra-nuclear densities inside neutron stars.
Improvements in electromagnetic and gravitational wave sensing instruments
continue to enhance the accuracy with which they can measure the masses, radii,
and tidal def... | 1812.06126v1 |
2019-05-06 | Proximate Molecular Quasar Absorbers: Excess of damped H2 systems at zabs~zQSO in SDSS DR14 | We present results from a search for strong H2 absorption systems proximate
to quasars (zabs~zem) in the Sloan Digital Sky Survey (SDSS) Data Release 14.
The search is based on the Lyman-Werner band signature of damped H2 absorption
lines without any prior on the associated metal or neutral hydrogen content.
This has r... | 1905.02040v1 |
2019-11-12 | Self Sustained Thermally Induced Gas-Damped Oscillations of Bimetal Cantilevers with Application to the Design of a New Pyroelectric Micro Energy Harvester | Low efficiency is the main drawback of many MEMS thermal energy harvesters.
Recently, energy harvesting micro-devices that operate using the pyroelectric
effect gained attention due to their potential superior performance. Operation
of these devices is based on the cyclic motion of a pyroelectric capacitor that
operate... | 1911.04823v1 |
2020-04-22 | A Significantly Neutral Intergalactic Medium Around the Luminous z=7 Quasar J0252-0503 | Luminous $z\ge7$ quasars provide direct probes of the evolution of
supermassive black holes (SMBHs) and the intergalactic medium (IGM) during the
epoch of reionization (EoR). The Ly$\alpha$ damping wing absorption imprinted
by neutral hydrogen in the IGM can be detected in a single EoR quasar spectrum,
allowing the mea... | 2004.10877v1 |
2021-02-01 | On a Possible Solution to the Tidal Realignment Problem for Hot Jupiters | Hot stars with hot Jupiters have a wide range of obliquities, while cool
stars with hot Jupiters tend to have low obliquities. An enticing explanation
for this pattern is tidal realignment of the cool host stars, although this
explanation assumes that obliquity damping occurs faster than orbital decay, an
assumption th... | 2102.01081v2 |
2021-02-22 | Slow-Mode Magnetoacoustic Waves in Coronal Loops | Rapidly decaying long-period oscillations often occur in hot coronal loops of
active regions associated with small (or micro-) flares. This kind of wave
activity was first discovered with the SOHO/SUMER spectrometer from Doppler
velocity measurements of hot emission lines, thus also often called "SUMER"
oscillations. T... | 2102.11376v1 |
2021-11-22 | Recent Developments in Quantum-Circuit Refrigeration | We review the recent progress in direct active cooling of the
quantum-electric degrees freedom in engineered circuits, or quantum-circuit
refrigeration. In 2017, the invention of a quantum-circuit refrigerator (QCR)
based on photon-assisted tunneling of quasiparticles through a
normal-metal--insulator--superconductor j... | 2111.11234v1 |
2017-06-16 | Damping of Rabi oscillations in intensity-dependent photon echoes from exciton complexes in a CdTe/(Cd,Mg)Te single quantum well | We study Rabi oscillations detected in the coherent optical response from
various exciton complexes in a 20~nm-thick CdTe/(Cd,Mg)Te quantum well using
time-resolved photon echoes. In order to evaluate the role of exciton
localization and inhomogeneous broadening we use selective excitation with
spectrally narrow ps-pul... | 1706.05327v1 |
2017-06-28 | Generating Log-normal Mock Catalog of Galaxies in Redshift Space | We present a public code to generate a mock galaxy catalog in redshift space
assuming a log-normal probability density function (PDF) of galaxy and matter
density fields. We draw galaxies by Poisson-sampling the log-normal field, and
calculate the velocity field from the linearised continuity equation of matter
fields,... | 1706.09195v2 |
2018-02-16 | Quantitative Constraints on the Reionization History from the IGM Damping Wing Signature in Two Quasars at z > 7 | During reionization, neutral hydrogen in the intergalactic medium (IGM)
imprints a damping wing absorption feature on the spectrum of high-redshift
quasars. A detection of this signature provides compelling evidence for a
significantly neutral Universe, and enables measurements of the hydrogen
neutral fraction $x_{\rm ... | 1802.06066v1 |
2018-02-16 | Landau Damping in a strong magnetic field: Dissociation of Quarkonia | We have investigated the effects of strong magnetic field on the properties
of quarkonia immersed in a thermal medium of quarks and gluons and studied its
quasi-free dissociation due to the Landau-damping. Thermalizing the Schwinger
propagator in the lowest Landau levels for quarks and the Feynman propagator
for gluons... | 1802.06874v1 |
2018-07-04 | Constraints on reionisation from the z=7.5 QSO ULASJ1342+0928 | The recent detection of ULASJ1342+0928, a bright QSO at $z=7.54$, provides a
powerful probe of the ionisation state of the intervening intergalactic medium,
potentially allowing us to set strong constraints on the epoch of reionisation
(EoR). Here we quantify the presence of Ly$\alpha$ damping wing absorption from
the ... | 1807.01593v1 |
2018-07-04 | Stellar masses, metallicity gradients and suppressed star formation revealed in a new sample of absorption selected galaxies | Context. Absorbing galaxies are selected via the detection of characteristic
absorption lines which their gas-rich media imprint in the spectra of distant
light-beacons. The proximity of the typically faint foreground absorbing
galaxies to bright background sources makes it challenging to robustly identify
these in emi... | 1807.01755v1 |
2018-07-05 | Stationarity and energy transfer in out-of-equilibrium systems | We define a characteristic energy density based on the measurement of the two
first moments of the extrinsic injected power smoothed over time. Using the
stationarity, we show that this definition characterizes an energy per degrees
freedom of the intrinsic dissipation. Our framework can be applied to systems
in contac... | 1807.01856v1 |
2018-10-25 | Time-retarded damping and magnetic inertia in the Landau-Lifshitz-Gilbert equation self-consistently coupled to electronic time-dependent nonequilibrium Green functions | The conventional Landau-Lifshitz-Gilbert (LLG) equation is a widely used tool
to describe dynamics of local magnetic moments, viewed as classical vectors of
fixed length, with their change assumed to take place simultaneously with the
cause. Here we demonstrate that recently developed [M. D. Petrovi\'{c} {\em et
al.}, ... | 1810.11016v2 |
2019-07-17 | Sub-damped Lyman alpha systems in the XQ-100 survey I -- Identification and contribution to the cosmological HI budget | Sub-damped Lyman alpha systems (subDLAs; HI column densities of
19.0<=logN(HI)<20.3) are rarely included in the cosmic HI census performed at
redshifts z>=1.5, yet are expected to contribute significantly to the overall
HI mass budget of the Universe. In this paper, we present a blindly selected
sample of 155 subDLAs f... | 1907.07703v1 |
2019-10-28 | Investigating the damping rate of phase-mixed Alfven waves | Context: This paper investigates the effectiveness of phase mixing as a
coronal heating mechanism. A key quantity is the wave damping rate, $\gamma$,
defined as the ratio of the heating rate to the wave energy.
Aims: We investigate whether or not laminar phase-mixed Alfv\'en waves can
have a large enough value of $\g... | 1910.12510v1 |
2020-03-01 | Positivity and nonadditivity of quantum capacities using generalized erasure channels | We consider various forms of a process, which we call {\em gluing}, for
combining two or more complementary quantum channel pairs
$(\mathcal{B},\mathcal{C})$ to form a composite. One type of gluing combines a
perfect channel with a second channel to produce a \emph{generalized erasure
channel} pair $(\mathcal{B}_g,\mat... | 2003.00583v2 |
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