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astro-ph/9510090
The Canada France Redshift Survey VIII: Evolution of the clustering of galaxies from z~1
We have used the projected two-point correlation function, $w(r_p)$, to investigate the spatial distribution of the 591 galaxies with secure redshifts between $0 \leq z \leq 1.3$ in the five CFRS fields. The slope of the two-point correlation function for the sample as a whole is $\gamma=1.64\pm0.05$, very similar to...
1995-10-18
2016-08-30
[ "astro-ph" ]
O. Le Fevre, D. Hudon, S.J. Lilly, D. Crampton, F. Hammer, L. Tresse
astro-ph/9510088
Mid-Infrared Imaging of Young Stellar Objects
We present arcsecond resolution mid-infrared (8--13 $\mu$m) images and photometry of four young stellar objects (YSOs)~--- L1551-IRS5, HL~Tau, AS~205, and AS~209 (V1121~Oph)~--- taken with the Berkeley Mid-Infrared Camera. For AS~205, a known T Tauri binary, we also present near-infrared JHK images and HKL$^{\prime}$ s...
1995-10-18
2009-10-28
[ "astro-ph" ]
Michael C. Liu, James R. Graham (UC Berkeley), A.M. Ghez (UCLA), M. Meixner (UIUC), C.J. Skinner, Eric Keto, Roger Ball (IGPP/LLNL), J.F. Arens, and J.G. Jernigan (SSL/UC Berkeley)
astro-ph/9510091
Cluster Dynamics and Cluster Masses
In spite of the promise of new techniques for constraining the mass distribution in galaxy clusters, much remains to be learned from galaxy orbital velocities. This article reviews the theory of potential estimation in hot dynamical systems like galaxy clusters. An analysis is presented of the Coma cluster, based on a ...
1995-10-18
2007-05-23
[ "astro-ph" ]
David Merritt and Karl Gebhardt (Rutgers University)
astro-ph/9510082
The Baryon Catastrophe and the multiphase intracluster medium
We review the theories and observations which together have led to the concept of the Baryon Catastrophe: observations of the baryon fraction on the scale of clusters of galaxies appear to be at least three times as high as the universal baryon fraction predicted by the theory of primordial nucleosynthesis in a flat, $...
1995-10-17
2015-06-24
[ "astro-ph" ]
K. F. Gunn and P. A. Thomas
astro-ph/9510103
X-ray Timing and Spectral Behavior of the Rapid Burster
We present an X-ray fast-timing and spectral analysis of the type II bursts and the persistent emission (PE) of the Rapid Burster observed with the EXOSAT Medium-Energy Instrument. The Hardness-Intensity and Color-Color Diagrams of the Rapid Burster are somewhat different from those of the majority of other low-mass X-...
1995-10-17
2015-06-24
[ "astro-ph" ]
Robert Rutledge, Lori Lubin, Walter Lewin, Brian Vaughan, Jan van Paradijs, Michiel van der Klis
astro-ph/9510086
The energetics of flat and rotating early-type galaxies and their X-ray luminosity
The global energy budget of the hot gas flows in early-type galaxies is used to explain the recent observational results that S0 galaxies have lower mean X-ray luminosity $L_X$ per unit optical luminosity $L_B$ than do ellipticals. This could be explained with a higher heat input or with a lower gravitational energy (a...
1995-10-17
2015-06-24
[ "astro-ph" ]
L. Ciotti (Osservatorio Astronomico di Bologna) and S. Pellegrini (Dipartimento di Astronomia, Bologna)
astro-ph/9510085
The history of star formation of starburst galaxies
In this paper, we use different luminosity ratios to trace the histories of star formation of two different kinds of starburst galaxies: HII galaxies and starburst nucleus galaxies (SBNGs). The mean star formation rates (SFRs) for these galaxies is comparable, and compatible with a near constant star formation over a f...
1995-10-17
2007-05-23
[ "astro-ph" ]
Roger Coziol (Astrophysics Division, Instituto Nacional de Pesquisas Espaciais (INPE))
astro-ph/9510083
Is the Accretion Flow in NGC 4258 Advection-dominated?
The mass of the central black hole in the active galaxy NGC 4258 (M106) has been measured to be $M=3.6\times10^7\Msun$ (Miyoshi et al. 1995). The Eddington luminosity corresponding to this mass is $L_E=4.5\times10^{45}$ erg s$^{-1}$. By contrast the X-ray luminosity of the nucleus of NGC 4258 between $2-10$ keV is $(4\...
1995-10-17
2009-10-28
[ "astro-ph" ]
J.-P. Lasota, M. A. Abramowicz, X. Chen, J. Krolik, R. Narayan and I. Yi
astro-ph/9510084
Thermal Instability of Advection-Dominated Disks against Local Perturbations
Thermal instability is examined for advection-dominated one-temperature accretion disks. We consider axisymmetric perturbations with short wavelength in the radial direction. The viscosity is assumed to be sufficiently small for the vertical hydrostatic balance to hold in perturbed states. The type of viscosity is give...
1995-10-17
2015-06-24
[ "astro-ph" ]
Shoji Kato, Marek A. Abramowicz and Xingming Chen
astro-ph/9510087
Chaos and Elliptical Galaxies
Recent results on chaos in triaxial galaxy models are reviewed. Central mass concentrations like those observed in early-type galaxies -- either stellar cusps, or massive black holes -- render most of the box orbits in a triaxial potential stochastic. Typical Liapunov times are 3-5 crossing times, and ensembles of stoc...
1995-10-17
2009-10-28
[ "astro-ph" ]
David Merritt (Rutgers University)
astro-ph/9510080
Locally Optimally Emitting Clouds and the Origin of Quasar Emission Lines
The similarity of quasar line spectra has been taken as an indication that the emission line clouds have preferred parameters, suggesting that the environment is subject to a fine tuning process. We show here that the observed spectrum is a natural consequence of powerful selection effects. We computed a large grid of ...
1995-10-16
2011-05-05
[ "astro-ph" ]
Jack Baldwin (CTIO), Gary Ferland, Kirk Korista and Dima Verner (Univ. Ky)
astro-ph/9510081
Radio Science Investigation on a Mercury Orbiter Mission
We review the results from {\it Mariner 10} regarding Mercury's gravity field and the results from radar ranging regarding topography. We discuss the implications of improving these results, including a determination of the polar component, as well as the opportunity to perform relativistic gravity tests with a future ...
1995-10-16
2009-10-28
[ "astro-ph", "gr-qc" ]
J. D. Anderson, S. G. Turyshev, S. W. Asmar, M. K. Bird, A. S. Konopliv, T. P. Krisher, E. L. Lau, G. Schubert and W. L. Sjogren
astro-ph/9510078
Star Formation and Chemical Evolution in Damped Lya Clouds
Using the redshift evolution of the neutral hydrogen density, as inferred from observations of damped Ly$\alpha$ clouds, we calculate the evolution of star formation rates and elemental abundances in the universe. For most observables our calculations are in rough agreement with previous results based on the instantane...
1995-10-16
2009-10-28
[ "astro-ph" ]
R.A. Malaney (CITA) and B. Chaboyer (CITA)
astro-ph/9510079
Probing the halo of Centaurus A: a merger dynamical model for the PN population
Photometry and kinematics of the giant elliptical galaxy NGC~5128 (Centaurus~A) based on planetary nebulae observations (Hui~\etal 1995) are used to build dynamical models which allow us to infer the presence of a dark matter halo. To this end, we apply a Quadratic Programming method. Constant mass-to-light ratio model...
1995-10-16
2007-05-23
[ "astro-ph" ]
A. Mathieu, H. Dejonghe and X. Hui
astro-ph/9510074
A Technical Memorandum On Core Radii In Lens Statistics
Quantitative estimates of lensing probabilities must be self-consistent. In particular, for asymptotically isothermal models: (1) using the $(3/2)^{1/2}$ correction for the velocity dispersion overestimates the expected number of lenses by 150\% and their average separations by 50\%, thereby introducing large cosmologi...
1995-10-15
2007-05-23
[ "astro-ph" ]
C.S. Kochanek (Harvard-Smithsonian Center For Astrophysics)
astro-ph/9510076
Deprojection of Axially Symmetric Objects
The deprojection of axisymmetric density distributions is generally indeterminate to within the addition of certain axisymmetric distributions (konus densities) that are invisible in projection. The known class of konus densities is expanded considerably here through the introduction of {\em semikonus functions}. These...
1995-10-15
2015-06-24
[ "astro-ph" ]
C.S. Kochanek & G.B. Rybicki (Harvard-Smithsonian Center For Astrophysics)
astro-ph/9510077
Is There A Cosmological Constant?
We present limits on the cosmological constant from the statistics of gravitational lenses using newly completed quasar surveys, new lens data, and a range of lens models. The formal limit is $\lambda_0 < 0.66$ at 95\% confidence in flat cosmologies, including the statistical uncertainties in the number of lenses, gala...
1995-10-15
2009-10-28
[ "astro-ph" ]
C.S. Kochanek (Harvard-Smithsonian Center For Astrophysics)
astro-ph/9510075
Gravitational Lenses and the Structure of Galaxies
Nearly singular isothermal mass distributions with small core radii are consistent with stellar dynamics, lens statistics, and lens models as a model for E/S0 galaxies. Models like the de Vaucouleurs model with a constant mass-to-light ratio are not. While the isothermal distributions are probably an oversimplification...
1995-10-15
2011-04-15
[ "astro-ph" ]
C.S. Kochanek (Harvard-Smithsonian Center For Astrophysics)
astro-ph/9510073
Conversion of neutron stars to strange stars as an origin of gamma-ray bursts
This paper argues that conversion of neutron stars to strange stars as an origin of cosmological stars in the binaries with low-mass companions. Our model may provide an explanation why the binary millisecond pulsars seem to have same low magnetic fields.
1995-10-14
2009-07-09
[ "astro-ph" ]
K. S. Cheng and Z. G. Dai
astro-ph/9510069
Obscured AGB stars in the Magellanic Clouds II. Near-infrared and mid-infrared counterparts
We have carried out an infrared search for obscured AGB stars in the Magellanic Clouds. The survey uncovered a number of obscured AGB stars as well as some supergiants with infrared excess. We present photometry of the sources and discuss the colour diagrams and bolometric luminosities. Most of the AGB stars are lumino...
1995-10-13
2015-06-24
[ "astro-ph" ]
Albert A. Zijlstra, Cecile Loup, L.B.F.M. Waters, P.A. Whitelock, Jacco Th. van Loon and F. Guglielmo
astro-ph/9510071
Statistical Connections Between the Properties of Type Ia Supernovae and the B--V Colors of Their Parent Galaxies, and the Value of H$_0$
Statistical connections between the properties of Type Ia supernovae (SNe Ia) and the B--V colors of their parent galaxies are established. Compared to SNe Ia in blue galaxies [B-V$\la$0.75], SNe Ia in redder galaxies have (1) a wider dispersion in the blueshifts of their Si II $\lambda$6355 absorption features, ten da...
1995-10-13
2016-08-30
[ "astro-ph" ]
David Branch, W. Romanishin, and E. Baron
astro-ph/9510070
Preliminary Spectral Analysis of SN 1994I
We present optical spectra of the Type Ic supernova 1994I in M51 and preliminary non-LTE analysis of the spectra. Our models are not inconsistent with the explosions of C+O cores of massive stars. While we find no direct evidence for helium in the optical spectra, our models cannot rule out small amounts of helium. Mor...
1995-10-13
2015-06-24
[ "astro-ph" ]
E. Baron, P. H. Hauschildt, D. Branch, R. P. Kirshner, and A. V. Filippenko
astro-ph/9510072
Looking for $\Lambda$ with the Rees-Sciama Effect
In models with a cosmological constant, a significant component of the large scale cosmic microwave background (CMB) anisotropy is produced at rather low redshifts, z < 1. In these models, the gravitational potential perturbations begin to evolve at late times. Photons passing through these time varying potentials aqui...
1995-10-13
2009-07-09
[ "astro-ph", "hep-ph" ]
Robert G. Crittenden and Neil Turok (Princeton University)
astro-ph/9510068
On Gravitational Collapse in the Nonsymmetric Gravitational Theory
The analytical structure of the difference between the static vacuum solution in the nonsymmetric gravitational theory (NGT) and the Schwarzschild solution of Einstein's gravitational theory (EGT) is studied. It is proved that a smooth matching of the solutions does not exist in the range $0 < r \leq 2M$, for any non-z...
1995-10-13
2007-05-23
[ "astro-ph", "gr-qc" ]
J. W. Moffat and I. Yu. Sokolov
astro-ph/9510065
Warm absorber, reflection and Fe K line in the X-ray spectrum of IC 4329A
Results from the X-ray spectral analysis of the ASCA PV phase observation of the Seyfert 1 galaxy IC 4329A are presented. We find that the 0.4 - 10 keV spectrum of IC 4329A is best described by the sum of a steep ($\Gamma \sim 1.98$) power-law spectrum passing through a warm absorber plus a strong reflection component ...
1995-10-12
2009-10-28
[ "astro-ph" ]
M. Cappi, T. Mihara, M. Matsuoka (RIKEN-Japan), K. Hayashida (Osaka University-Japan), K.A. Weaver (Johns Hopkins University-USA) and C. Otani (RIKEN-Japan)
astro-ph/9510066
Limits on diffusive shock acceleration in dense and incompletely ionised media
The limits imposed on diffusive shock acceleration by upstream ion-neutral Alfven wave damping, and by ionisation and Coulomb losses of low energy particles, are calculated. Analytic solutions are given for the steady upstream wave excitation problem with ion-neutral damping and the resulting escaping upstream flux cal...
1995-10-12
2008-02-03
[ "astro-ph" ]
L O'C Drury (Dublin Institute for Advanced Studies, Dublin, Ireland), P Duffy, J G Kirk (MPI fuer Kernphysik, Heidelberg, Germany)
astro-ph/9510067
Dynamical Constraints on the Formation of Elliptical Galaxies
Recent work on the construction of spherical, Axisymmetric and triaxial dynamical models for elliptical galaxies is reviewed briefly, including their role in providing evidence for dark halos and central black holes. The different orbital structures and shapes of low-mass and giant elliptical galaxies provide essential...
1995-10-12
2007-05-23
[ "astro-ph" ]
P. T. de Zeeuw and C. M. Carollo
astro-ph/9510060
A New Method for Obtaining Binary Pulsar Distances and its Implications for Tests of General Relativity
We demonstrate how measuring orbital period derivatives can lead to more accurate distance estimates and transverse velocities for some nearby binary pulsars. In many cases this method will estimate distances more accurately than is possible by annual parallax, as the relative error decreases as t^-5/2. Unfortunately, ...
1995-10-11
2009-10-28
[ "astro-ph" ]
J. F. Bell and M. Bailes
astro-ph/9510063
Microlensing of disk sources
We analyse the effects on the predictions for the microlensing searches toward the Galactic bulge coming from the fact that not all the stars monitored belong to the bulge itself, but that a non--negligible fraction of them actually are in the Galactic disk. The different distribution and motions of these disk stars ...
1995-10-11
2009-10-28
[ "astro-ph" ]
S. Mollerach and E. Roulet
astro-ph/9510064
Is the X-ray spectrum of the Seyfert 2 galaxy NGC5252 intrinsically flat?
The first X-ray observation of the Seyfert 2 galaxy NGC5252 is reported. ASCA collected $\sim 4000$ photons/detector enough to perform an accurate spectral analysis of this source. The luminosity of NGC5252 is L$_{\rm X}$(0.7-10 keV) $\simeq 2.6 \times 10^{43}$ erg s$^{-1}$, typical of a Seyfert 1 galaxy. A simple desc...
1995-10-11
2009-10-28
[ "astro-ph" ]
M. cappi, T. Mihara, M. Matsuoka (RIKEN-Japan), W. Brinkmann, M. A. Prieto (MPE-FRG) and G.G.C. Palumbo (University of Bologna-Italy)
astro-ph/9510061
The Current Star Formation Rate of the Local Universe
The Universidad Complutense de Madrid (UCM) Survey is a long-term project aiming at finding and analysing star-forming galaxies detected by their H$\alpha$ emission in Schmidt objective-prism plates. The instrumental set-up limits the volume of the Universe surveyed to a redshift $z\lesssim0.045$. So far we have discov...
1995-10-11
2009-10-28
[ "astro-ph" ]
J. Gallego and J. Zamorano (University Complutense of Madrid), A. Aragon-Salamanca (Institute of Astronomy Cambridge), M. Rego (University Complutense of Madrid)
astro-ph/9510062
A Catalog of Digital Images of 113 Nearby Galaxies
We present a digital catalog of images of 113 galaxies in this paper. These galaxies are all nearby, bright, large and well resolved. All images were recorded with charge coupled devices (CCDs) at the Palomar Observatory with the 1.5 meter telescope and at the Lowell Observatory with the 1.1 meter telescope. At Palomar...
1995-10-11
2010-04-06
[ "astro-ph" ]
Zsolt Frei, Puragra Guhathakurta, James E. Gunn and J. Anthony Tyson
astro-ph/9510057
Cosmological Implications of Galaxy Cluster Evolution
We analyze with hydrodynamical simulations the evolution of galaxy clusters in a cosmological environment. Power ratios (Buote \& Tsai 1995) are used to quantitatively relate cluster morphologies to their dynamical states. The simulated clusters follow the same ``evolutionary track'' obeyed by a sample of low-redshift ...
1995-10-10
2015-06-24
[ "astro-ph" ]
John C. Tsai (CITA) and David A. Buote (MIT)
astro-ph/9510056
Averaging inhomogeneous Newtonian cosmologies
Idealizing matter as a pressureless fluid and representing its motion by a peculiar--velocity field superimposed on a homogeneous and isotropic Hubble expansion, we apply (Lagrangian) spatial averaging on an arbitrary domain $\cal D$ to the (nonlinear) equations of Newtonian cosmology and derive an exact, general equat...
1995-10-10
2011-09-29
[ "astro-ph", "gr-qc" ]
Thomas Buchert and Juergen Ehlers
astro-ph/9510055
Standard Cosmology and the BATSE Number vs. Peak Flux Distribution
The observed 2B BATSE distribution is consistent with the faintest GRBs in our sample originating from a redshift of Zmax ~ 0.8-3.0 (90\%), with the most likely values in the range of 1.0-2.2, and is largely insensitive to Omega for models with no evolution. To constrain the model parameter Omega to the range 0.1-1.0 u...
1995-10-10
2015-06-24
[ "astro-ph" ]
Robert Rutledge, Lam Hui, Walter H.G. Lewin (MIT)
astro-ph/9510054
Intergalactic Hydrogen Clouds at Low-Redshift: Connections To Voids And Dwarf Galaxies
We provide new post-COSTAR data on one sightline (Mrk 421) and updated data from another (I Zw 1) from our Hubble Space Telescope (HST) survey of intergalactic Lyman-alpha clouds located along sightlines to four bright quasars passing through well-mapped galaxy voids (16,000 km/s pathlength) and superclusters (18,000 k...
1995-10-10
2007-05-23
[ "astro-ph" ]
J. Michael Shull, John T. Stocke and Steve Penton (Center for Astrophysics and Space Astronomy, Department of Astrophysical, Planetary, and Atmospheric Sciences, University of Colorado, Boulder CO)
astro-ph/9510058
Mass Estimates of X-Ray Clusters
We use cosmological gas dynamic simulations to investigate the accuracy of galaxy cluster mass estimates based on X-ray observations. The experiments follow the formation of clusters in different cosmological models and include the effects of gravity, pressure gradients, and hydrodynamical shocks. A subset of our ensem...
1995-10-10
2009-10-28
[ "astro-ph" ]
August E. Evrard (University of Michigan Department of Physics), Christopher A. Metzler (NASA/Fermilab Astrophysics Center), and Julio F. Navarro (Steward Observatory, University of Arizona)
astro-ph/9510059
The Role of Time in Physical Cosmology
Recent advances in observational cosmology are changing the way we view the nature of time. In general relativity, the freedom in choosing a time hypersurface has hampered the implementation of the theory. Fortunately, Hamilton-Jacobi theory enables one to describe all time hypersurfaces on an equal footing. Using an e...
1995-10-10
2007-05-23
[ "astro-ph", "gr-qc", "hep-ph" ]
D. S. Salopek
astro-ph/9510052
Quantifying the Fragility of Galactic Disks in Minor Mergers
We perform fully self-consistent stellar dynamical simulations of the accretion of a companion ("satellite") galaxy by a large disk galaxy to investigate the interaction between the disk, halo, and satellite components of the system during a merger. Our fiducial encounter begins with a satellite in a prograde, circular...
1995-10-09
2009-10-28
[ "astro-ph" ]
Ian R. Walker, J. Christopher Mihos, and Lars Hernquist (UC Santa Cruz)
astro-ph/9510053
Formation of Massive Counterrotating Disks in Spiral Galaxies
We present results of numerical simulations of the formation of a massive counterrotating gas disk in a spiral galaxy. Using a hierarchical tree gravity solver combined with a sticky-particle gas dissipation scheme for our simulations, we have investigated three mechanisms: episodic and continuous gas infall, and a mer...
1995-10-09
2016-08-30
[ "astro-ph" ]
Aniruddha R. Thakar and Barbara S. Ryden (Ohio State University)
astro-ph/9510051
Galaxy Number Counts
In these Lectures Notes I re-visit the problem of the deep number counts as a viable method to (1) study the evolution of the galaxy population in the past and (2) determine the value of the deceleration parameter $q_0$. After a brief description of the basic concepts needed to model the counts, we show that simple lum...
1995-10-09
2007-05-23
[ "astro-ph" ]
Ana Campos (Dept. Physics, U. Durham)
astro-ph/9510049
The Nonlinear Redshift Space Power Spectrum: Omega from Redshift Surveys
We examine the anisotropies in the power spectrum by the mapping of real to redshift space. Using the Zel'dovich approximation, we obtain an analytic expression for the nonlinear redshift space power spectrum in the distant observer limit. For a given unbiased galaxy distribution in redshift space, the anisotropies in ...
1995-10-08
2016-06-08
[ "astro-ph" ]
K.B. Fisher, A. Nusser
astro-ph/9510046
A Theory of Extrasolar Giant Planets
We present a broad suite of models of extrasolar giant planets (EGP's), ranging in mass from 0.3 to 15 Jupiter masses. The models predict luminosity (both reflected and emitted) as a function of age, mass, deuterium abundance and distance from parent stars of various spectral type. We also explore the effects of helium...
1995-10-08
2009-10-28
[ "astro-ph" ]
D. Saumon, W.B. Hubbard, A. Burrows, T. Guillot, J.I. Lunine, and G. Chabrier
astro-ph/9510047
Galaxies at z=2: extensions around radio-quiet QSOs
We have been conducting an imaging survey to detect host galaxies of radio-quiet QSOs at high redshift (z = 2), in order to compare them with those of radio-loud objects. Six QSOs were observed in the R passband with the auxiliary port of the 4.2m WHT of the {\it Observatorio de Roque de los Muchachos} indir August 199...
1995-10-08
2007-05-23
[ "astro-ph" ]
I. Aretxaga, B.J. Boyle, R.J. Terlevich
astro-ph/9510045
Detection of Massive Forming Galaxies at Redshifts Greater than One
The complex problem of when and how galaxies formed has not until recently been susceptible of direct attack. It has been known for some time that the excessive number of blue galaxies counted at faint magnitudes implies that a considerable fraction of the massive star formation in the universe occurred at z < 3, but, ...
1995-10-08
2009-10-28
[ "astro-ph" ]
Lennox L. Cowie, Esther M. Hu, and Antoinette Songaila (Univ. of Hawaii, IfA)
astro-ph/9510050
Lensing by Distant Clusters: HST Observations of Weak Shear in the Field of 3C324
We present the detection of weak gravitational lensing in the field of the radio galaxy 3C324 (z=1.206) using deep HST imaging. ~From an analysis of the shapes of faint R=24.5-27.5 galaxies in the field we measure a weak, coherent distortion centered close to the radio source. This shear field most likely arises from g...
1995-10-08
2009-10-28
[ "astro-ph" ]
Ian Smail & Mark Dickinson
astro-ph/9510048
The Core of Cluster-Lenses
The gravitational lensing of faint background galaxies by rich clusters is emerging as a very efficient method to constrain both the mass distribution of cluster of galaxies and probe the statistical properties of faint background galaxies. We review here the results concerning the core of cluster lenses, where recent ...
1995-10-08
2007-05-23
[ "astro-ph" ]
J.-P. Kneib, G. Soucail
astro-ph/9510042
Small-Scale Power Spectrum and Correlations in LCDM
Cosmological models with a positive cosmological constant and $\Omega_0<1$ have a number of attractive features. A larger Hubble constant, which can be compatible with the recent HST estimate, and a large fraction of baryon density in galaxy clusters make them current favorites. Early galaxy formation also is considere...
1995-10-06
2007-05-23
[ "astro-ph" ]
Anatoly Klypin, Joel Primack, Jon Holtzman
astro-ph/9510040
Detection of the Angular Correlation of Faint X-ray Sources
We have analyzed a set of deep ROSAT observations with a total sky coverage of 40 square degrees to search for clustering of faint X-ray sources. Using the resulting catalog of discrete X-ray sources, we detect, for the first time in X-rays, a positive correlation on angular scales of 0.5'-10'. When corrected for a bia...
1995-10-06
2009-10-28
[ "astro-ph" ]
A. Vikhlinin and W. Forman
astro-ph/9510038
An Incoherent $\alpha-\Omega$ Dynamo in Accretion Disks
We use the mean-field dynamo equations to show that an incoherent alpha effect in mirror-symmetric turbulence in a shearing flow can generate a large scale, coherent magnetic field. We illustrate this effect with simulations of a few simple systems. In accretion disks, this process can lead to axisymmetric magnetic dom...
1995-10-06
2015-06-24
[ "astro-ph" ]
Ethan T. Vishniac (U. Texas) and Axel Brandenburg (Nordita)
astro-ph/9510041
Higher-Order Gravitational Perturbations of the Cosmic Microwave Background
We study the behavior of light rays in perturbed Robertson-Walker cosmologies, calculating the redshift between an observer and the surface of last scattering to second order in the metric perturbation. At first order we recover the classic results of Sachs and Wolfe, and at second order we delineate the various new ef...
1995-10-06
2008-11-26
[ "astro-ph", "gr-qc" ]
Ted Pyne and Sean M. Carroll
astro-ph/9510034
Galaxy Harassment and the Evolution of Clusters of Galaxies
Disturbed spiral galaxies with high rates of star formation pervaded clusters of galaxies just a few billion years ago, but nearby clusters exclude spirals in favor of ellipticals. ``Galaxy harassment" (frequent high speed galaxy encounters) drives the morphological transformation of galaxies in clusters, provides fuel...
1995-10-06
2009-10-28
[ "astro-ph" ]
Ben Moore, Neal Katz, George Lake, Alan Dressler & Augustus Oemler
astro-ph/9510039
Evaporation of cosmological quark drops and relativistic radiative transfer
We discuss the results of a full relativistic treatment of the hydrodynamics of disconnected quark regions during the final stages of the cosmological quark-hadron transition. In this study, which represents a further development of a previous analysis of the evaporation of cosmological quark drops, the effects of long...
1995-10-06
2009-10-28
[ "astro-ph", "hep-ph" ]
L. Rezzolla and J. C. Miller
astro-ph/9510043
Femtolensing and Picolensing by Axion Miniclusters
Non-linear effects in the evolution of the axion field in the early Universe may lead to the formation of gravitationally bound clumps of axions, known as ``miniclusters.'' Minicluster masses and radii should be in the range $M_{\rm mc}\sim10^{-12} M_\odot$ and $R_{\rm mc} \sim 10^{10}$cm, and in plausible early-Univer...
1995-10-06
2009-10-28
[ "astro-ph", "hep-ph" ]
E. W. Kolb and I. I. Tkachev
astro-ph/9510044
Compact Objects without Events Horizon
It is shown that gravitational theory allows stable equilibrium configurations of the degenerated Fermi gas, whose masses are many times as large as the Sun. They have no events horizon at the Schwarzchild radius from the center. They are objects with low luminosity and they are new candidates to Dark Matter in the Uni...
1995-10-06
2008-02-03
[ "astro-ph" ]
L. V. Verozub
astro-ph/9510036
The Acceleration of Electrons In Radio Supernova SN1986J
We propose a model for radio supernovae (RSN) based on the synchrotron emission from relativistic electrons which are diffusively accelerated at the expanding supernova shock. This model was originally developed for application to the optically thin emission observed from SN1987A. Here we generalise it by including the...
1995-10-06
2011-05-23
[ "astro-ph" ]
Lewis Ball (Research Centre for Theoretical Astrophysics, University of Sydney, NSW, Australia) J.G. Kirk (Max-Planck-Institut fuer Kernphysik, Heidelberg, Germany)
astro-ph/9510035
Advanced Statistical Methods for Large-Scale Structure Studies
These Lecture Notes are devoted to an introductory description of some of the most widely applied statistical methods for the analysis of the Large-Scale Structure (LSS) of the Universe. Rather than providing technical details about the implementation of such methods, I concentrate more on their significance and on the...
1995-10-06
2007-05-23
[ "astro-ph" ]
Stefano Borgani
astro-ph/9510027
The debate of galaxy correlations and its theoretical implications
We discuss the problem of galaxy correlations by considering the various methods by which this information can be obtained. We focus in particular on the volume limited three dimensional samples and discuss a new way to increase the scale of their statistical validity. From our previous results and the most recent ones...
1995-10-05
2007-05-23
[ "astro-ph" ]
L. Pietronero, M. Montuori and F. Sylos Labini
astro-ph/9510030
Cosmic Error and the Statistics of Large Scale Structure
We examine the errors on counts in cells extracted from galaxy surveys. The measurement error, related to the finite number of sampling cells, is disentangled from the ``cosmic error'', due to the finiteness of the survey. Using the hierarchical model and assuming locally Poisson behavior, we identified three contribut...
1995-10-05
2009-10-28
[ "astro-ph" ]
Istv\'an Szapudi and St\'ephane Colombi
astro-ph/9510031
Analysis of the Polarization and Flux Spectra of SN1993J
Synthetic polarization and flux spectra are presented for aspherical, electron scattering-dominated photospheres of Type II supernovae (SN II) in general and the specific case of SN 1993J using a Monte Carlo scheme. The observed luminosity of a Type II supernova depends on the unknown inclination angle. Spectral anal...
1995-10-05
2016-08-30
[ "astro-ph" ]
P. Hoeflich, J.C. Wheeler, D.C. Hines, S.R. Trammell
astro-ph/9510028
Advection-Dominated Models of Luminous Accreting Black Holes
It has been found that a class of optically-thin two-temperature advection-dominated accretion solutions explains many observations of low-luminosity accreting black holes. Here it is shown that these models give a satisfactory description also of higher luminosity systems, provided the viscosity parameter $\alpha$ is ...
1995-10-05
2009-10-28
[ "astro-ph" ]
Ramesh Narayan
astro-ph/9510026
Variations in Solar Luminosity from Time Scales of Minutes to Months
We present the power spectrum of solar irradiance during 1985 and 1987 obtained from the ACRIM project from time scales of minutes to months. At low frequency the spectra are Lorentzian. At higher frequencies they are proportional to $f^{-{1/2}}$. A linear, stochastic model of the turbulent heat transfer between the gr...
1995-10-05
2009-10-28
[ "astro-ph" ]
Jon D. Pelletier (Geological Sciences, Cornell U.)
astro-ph/9510029
Metric Perturbations from Quantum Tunneling in Open Inflation
We study the effect that quantum fluctuations produced during the nucleation of a single-bubble open inflationary universe have on the amplitude of temperature anisotropies in the microwave background. We compute the instanton action for the quantum tunneling between the false and true vacua in open inflation models an...
1995-10-05
2016-08-24
[ "astro-ph", "gr-qc" ]
Juan Garcia-Bellido
astro-ph/9510032
Spatial Distribution of the Starbursts in Post-Starburst Coma Cluster Galaxies
We present long slit spectra and multi-color CCD images which demonstrate that the strong star formation episodes that occurred in the post-starburst galaxies in the Coma Cluster and two field galaxies were not restricted to the central regions of the galaxies. Rather, the remnant young stars from the starbursts are fo...
1995-10-05
2009-10-28
[ "astro-ph" ]
Nelson Caldwell, James Rose, Marijn Franx, and Andrew Leonardi
astro-ph/9510033
The Ages of Starbursts in Post-Starburst Galaxies
We present a new technique for accurately determining the ages of starbursts in post-starburst galaxies. In particular, it uses the strength of the Ca II H + H$\epsilon$ absorption feature relative to that of Ca II K to separate the effects of burst strength from burst age in a spectrum comprised of a post-starburst po...
1995-10-05
2009-10-28
[ "astro-ph" ]
Andrew J. Leonardi and James A. Rose
astro-ph/9510037
Gravitational Dynamics in an Expanding Universe
The dynamical evolution of collisionless particles in an expanding background is described. After discussing qualitatively the key features, the gravitational clustering of collisionless particles in an expanding universe is modelled using some simple physical ideas. I show that it is indeed possible to understand the ...
1995-10-05
2007-05-23
[ "astro-ph" ]
T.Padmanabhan
astro-ph/9510018
The determination of $H_O$ by using the TF relation : About particular selection effects
This paper completes the statistical modeling of the Hubble flow when a Tully-Fisher type relation is used for estimating the absolute magnitude $M\approx a\,p+b$ from a line width distance indicator $p$. Our investigation is performed with the aim of providing us with a full understanding of statistical biases due to ...
1995-10-04
2007-05-23
[ "astro-ph" ]
R. Triay, S. Rauzy and M. Lachi\`eze-Rey
astro-ph/9510021
Three-Dimensional Hydrodynamic Bondi-Hoyle Accretion. V. Specific Heat Ratio 1.01, Nearly Isothermal Flow
We investigate the hydrodynamics of three-dimensional classical Bondi-Hoyle accretion. A totally absorbing sphere of different sizes (1, 0.1 and 0.02 accretion radii) moves at different Mach numbers (0.6, 1.4, 3.0 and 10) relative to a homogeneous and slightly perturbed medium, which is taken to be an ideal, nearly iso...
1995-10-04
2007-05-23
[ "astro-ph" ]
M. Ruffert (Max-Planck-Institut fuer Astrophysik)
astro-ph/9510025
OY Car in Outburst: Balmer emission from the red star and the gas stream
We present observations of OY Car, obtained with the Anglo-Australian telescope, during a normal outburst in 1991. Two sinusoidal components are resolved in the Hbeta trailed spectra and we determine the location of the narrow component to be on the secondary star with a maximum contributed flux of ~2.5 per cent to the...
1995-10-04
2007-05-23
[ "astro-ph" ]
E.T.Harlaftis, T. R. Marsh
astro-ph/9510022
X-ray reflection in Galactic Black Hole Candidates: smeared edge profiles and resonant Auger destruction
We consider the spectra of Thomson-thick, geometrically-thin accretion discs around Galactic black hole candidates in the reflection model and compute their iron K edges and iron K$\alpha$ lines. We compare the smeared iron K edge profiles that we compute with observation and find them to be a satisfactory description ...
1995-10-04
2015-06-24
[ "astro-ph" ]
R.R. Ross, A.C. Fabian, W.N. Brandt
astro-ph/9510016
The Nature of the Galactic Dark Matter
Disk-halo models of the Galaxy and LMC are constructed and used to analyse the microlensing data-set. Deflectors in the LMC bar, disk and halo provide an optical depth to microlensing of $\sim 2 \times 10^{-7}$. Deflectors in the Galactic disk and halo contribute $\sim 5 \times 10^{-7}$. The extent, flattening and velo...
1995-10-04
2016-06-08
[ "astro-ph" ]
N.W.Evans
astro-ph/9510015
Multifrequency Observations of Gamma-Ray Burst
Neither a flaring nor a quiescent counterpart to a gamma-ray burst has yet been convincingly identified at any wavelength region. The present status of the search for counterparts of classical gamma-ray bursts is given. Particular emphasis is put on the search for flaring counterparts, i.e. emission during or shortly a...
1995-10-04
2007-05-23
[ "astro-ph" ]
J. Greiner
astro-ph/9510014
Power spectrum for fractal distributions
We study the behaviour of the power spectrum (PS) in the case of fractal structures. We show that in this case the main observational features of the PS, the large scale flattening and the scaling of the amplitude with sample depth, are related to finite size effects, due to the fractal nature of galaxy distribution in...
1995-10-04
2007-05-23
[ "astro-ph" ]
F. Sylos Labini and L. Amendola
astro-ph/9510020
The Tully-Fisher relation : Correspondence between the Inverse and Direct approaches
In a previous paper, we have demonstrated the importance to define a statistical model describing the observed linear correlation between the absolute magnitude $M$ and the log line width distance indicator $p$ of galaxies (the Tully-Fisher relation). As long as the same statistical model is used during the calibration...
1995-10-04
2007-05-23
[ "astro-ph" ]
S. Rauzy and R. Triay
astro-ph/9510024
Stellar Equilibrium and Gravitational Collapse in the Nonsymmetric Gravitational Theory
We establish the formalism in the nonsymmetric gravitational theory (NGT) for stellar equilibrium and gravitational collapse. We study the collapse of a pressureless, spherically symmetric dust cloud. By assuming that the interior solution is smoothly matched at the surface of the star to the quasi-static, spherically ...
1995-10-04
2008-02-03
[ "astro-ph", "gr-qc" ]
J. W. Moffat
astro-ph/9510019
Cosmic Microwave Background Anisotropies from the Rees-Sciama Effect in $\Omega_{0} \le 1$ Universes
We investigate the imprint of nonlinear matter condensations on the Cosmic Microwave Background (CMB) in $\Omega_{0}<1$ cold dark matter (CDM) model universes. We consider simulation domains ranging from $120h^{-1}$ Mpc to $360h^{-1}$ Mpc in size. We concentrate on the secondary temperature anisotropies induced by time...
1995-10-04
2008-11-26
[ "astro-ph" ]
Robin Tuluie, Pablo Laguna (Penn State) and Peter Anninos (NCSA)
astro-ph/9510017
Wavelet Analysis of Inhomogeneous Data with Application to the Cosmic Velocity Field
In this article we give an account of a method of smoothing spatial inhomogeneous data sets by using wavelet reconstruction on a regular grid in an auxilliary space onto which the original data is mapped. In a previous paper by the present authors, we devised a method for inferring the velocity potential from the radia...
1995-10-04
2009-10-28
[ "astro-ph" ]
S. Rauzy, M. Lachi\`eze-Rey and R.N. Henriksen
astro-ph/9510023
Microlensing By a Prolate All-Macho Halo
It is widely believed that dark matter halos are flattened, that is closer to oblate than prolate. The evidence cited is based largely on observations of galaxies which do not look anything like our own and on numerical simulations which use ad hoc initial conditions. Given what we believe to be a ``reasonable doubt'' ...
1995-10-04
2009-10-28
[ "astro-ph" ]
Gilbert P. Holder, Lawrence M. Widrow
astro-ph/9510013
On the interpretation of the He II absorption in the line of sight of Q0302-003
We point out the peculiarities of the line of sight of Q0302-003 which was recently used to estimate the He II opacity at $z \sim 3.285$. This line of sight contains a large void in Lyman $\alpha$ clouds, in the region used for the He II opacity observation, and the void is thought to be caused by the ionizing radiatio...
1995-10-04
2015-06-24
[ "astro-ph" ]
Biman B. Nath and Shiv K. Sethi
astro-ph/9510010
Chaos, Fractals and Inflation
In order to draw out the essential behavior of the universe, investigations of early universe cosmology often reduce the complex system to a simple integrable system. Inflationary models are of this kind as they focus on simple scalar field scenarios with correspondingly simple dynamics. However, we can be assured that...
1995-10-03
2009-10-28
[ "astro-ph", "gr-qc", "hep-th" ]
Neil J. Cornish (CWRU) and Janna J. Levin (CfPA, Berkeley)
astro-ph/9510008
Hydrodynamic accretion onto rapidly rotating Kerr black hole
Bondi type hydrodynamic accretion of the surrounding matter onto Kerr black hole with an arbitrary rotational parameter is considered. The effects of viscosity, thermal conductivity and interaction with radiation field are neglected. The black hole is supposed to be at rest with respect to matter at infinity. The flow ...
1995-10-03
2015-06-24
[ "astro-ph" ]
Vladimir I.Pariev (P.N.Lebedev Physical Institute, Moscow)
astro-ph/9510012
Weak Lensing and the Sloan Digital Sky Survey
While the strategy for the first applications of weak lensing has been to ``go deep'' it is equally interesting to use one's telescope time to instead ``go wide''. The Sloan Survey (SDSS) provides a natural framework for a very wide area weak lensing survey.
1995-10-03
2011-04-12
[ "astro-ph" ]
Albert Stebbins, Tim Mckay, and Joshua A. Frieman
astro-ph/9510007
High-Energy Spectral Complexity from Thermal Gradients in Black Hole Atmospheres
We show that Compton scattering of soft photons with energies near 100 eV in thermally stratified black-hole accretion plasmas with temperatures in the range 100 keV - 1 MeV can give rise to an X-ray spectral hardening near 10 keV. This could produce the hardening observed in the X-ray spectra of black holes, which is ...
1995-10-03
2009-10-28
[ "astro-ph" ]
J. G. Skibo and C. D. Dermer (Naval Research Laboratory)
astro-ph/9510009
Strong X-ray Absorption in a BALQSO: PHL5200
We present $\it {ASCA}$ observations of the z=1.98 prototype BALQSO: PHL5200. The source was detected in both SIS and GIS. A power-law spectrum ($\alpha_E = 0.6^{+0.9}_{-0.6}$) with large intrinsic absorption (N$_H = 1.3^{+2.3}_{-1.1} \times 10^{23}$ cm$^{-2}$) best describes the spectrum. Excess column density over th...
1995-10-03
2007-05-23
[ "astro-ph" ]
Smita Mathur, Martin Elvis & K. P. Singh
astro-ph/9510011
Fragmentation in a centrally condensed protostar
Hydrodynamical calculations in three space dimensions of the collapse of an isothermal, centrally condensed, rotating 1 M\sol protostellar cloud are presented. A numerical algorithm involving nested subgrids is used to resolve the region where fragmentation occurs in the central part of the protostar. A previous calcul...
1995-10-03
2007-05-23
[ "astro-ph" ]
Andi Burkert, Peter Bodenheimer
astro-ph/9510006
Optical Detection of the Hidden Nuclear Engine in NGC~4258
The sub-parsec masing disk recently found to be orbiting a central mass of $\sim3.6\times10^7$~\msun\ in the Seyfert/LINER galaxy NGC~4258 provides the most compelling evidence to date for the existence of a massive black hole in the nucleus of a galaxy. The disk is oriented nearly edge-on %($\bf i=83$\deg) and the X-r...
1995-10-03
2009-10-28
[ "astro-ph" ]
Belinda J. Wilkes (CfA), Gary D. Schmidt (Steward Observatory), Paul S. Smith (Steward Observatory), Smita Mathur (CfA), Kim K. McLeod (CfA)
astro-ph/9510001
Kinematics of ionized gas associated with the radio nucleus and lobes in the active galaxy IRAS 04210+0400
We have used high resolution longslit spectroscopy to investigate the ionized gas in the active galaxy IRAS 04210+0400 and its association with the radio structure. We suggest that two of the ionized components are associated with the central double radio source and observe that the relative positions of these compon...
1995-10-02
2015-06-24
[ "astro-ph" ]
A.J. Holloway (Manchester), W. Steffen (Manchester), A. Pedlar (NRAL), D.J. Axon (NRAL,STSCI), J.E. Dyson (Manchester), J. Meaburn (Manchester) and C.N. Tadhunter (Sheffield)
astro-ph/9510005
Spectral Properties of Accretion Disks Around Galactic and Extragalactic Black Holes
We study the spectral properties of a very general class of accretion disks which can be decomposed into three distinct components apart from a shock at $r=r_s$: (1) An optically thick Keplerian disk on the equatorial plane ($r>r_s$), (2) A sub-Keplerian optically thin halo above and below this Keplerian disk $r>r_s$ a...
1995-10-02
2009-10-28
[ "astro-ph" ]
Sandip K. Chakrabarti and Lev G. Titarchuk
astro-ph/9510003
The Neutral Hydrogen Disk of Arp 10 (=VV 362) : A Non-equilibrium Disk Associated with a Galaxy with Rings and Ripples
We present VLA \ion{H}{1} and optical spectra of the peculiar galaxy Arp~10. Originally believed to be an example of a classical colliding ring galaxy with multiple rings, the new observations show a large disturbed neutral hydrogen disk extending 2.7 times the radius of the bright optical ring. We also present evidenc...
1995-10-02
2009-10-28
[ "astro-ph" ]
V. Charmandaris and P. N. Appleton (Iowa State Univ.)
astro-ph/9510004
Evidence for a Spectroscopic Sequence Among SNe Ia
In this Letter we present evidence for a spectral sequence among Type Ia supernovae (SNe Ia). The sequence is based on the systematic variation of several features seen in the near-maximum light spectrum. This sequence is analogous to the recently noted photometric sequence among SNe Ia which shows a relationship betwe...
1995-10-02
2009-07-28
[ "astro-ph" ]
Peter Nugent, Mark Phillips, E. Baron, David Branch, and Peter Hauschildt
astro-ph/9510002
Deficit of Far-Infrared [CII] Line Emission toward the Galactic Center
We have observed the [CII] 158 micron line emission from the Galactic plane (-10 deg < l < 25 deg, |b| <= 3 deg) with the Balloon-borne Infrared Carbon Explorer (BICE). The observed longitudinal distribution of the [CII] line emission is clearly different from that of the far-infrared continuum emission; the Galactic c...
1995-10-02
2009-10-28
[ "astro-ph" ]
Takao Nakagawa, Yasuo Doi, Yukari Yamashita Yui, Haruyuki Okuda, Kenji Mochizuki, and Hiroshi Shibai (The Institute of Space and Astronautical Science), Tetsuo Nishimura and Frank J. Low (Steward Observatory, University of Arizona)
astro-ph/9509159
ROSAT PSPC observations of Cygnus-A : X-ray spectra of the cooling flow and hot spots
We present a {\it ROSAT} Position Sensitive Proportional Counter (PSPC) observation of the powerful radio galaxy Cygnus-A. The X-ray emission in the {\it ROSAT} band is dominated by thermal emission from the hot intracluster medium of the associated cluster. Image deprojection confirms the existence of a significant cl...
1995-10-01
2015-06-24
[ "astro-ph" ]
C.S. Reynolds, A.C. Fabian
astro-ph/9509160
Determination of the Hubble constant from observations of Cepheid variables in the galaxy M96
New Hubble Space Telescope observations of Cepheid variable stars in the nearby galaxy M96 give a distance to the host galaxy group, Leo-I, of 11.6+/-0.8 Mpc. This value, used in conjunction with several reliable secondary indicators of relative distance, constrains the distances to more remote galaxy clusters, and yie...
1995-10-01
2009-10-28
[ "astro-ph" ]
N.R. Tanvir, T. Shanks, H.C. Ferguson, D.R.T. Robinson
astro-ph/9509158
Classical Mechanics without Absolute Space
A relative mechanics with no absolute space is shown to be equivalent to Newtonian mechanics applied in a universe of zero net angular momentum. Closed spaces in General Relativity have no angular momentum and shrivel to one point as the mass-energy contained tends to zero, so obeying Mach's principle on the origin of ...
1995-10-01
2009-10-28
[ "astro-ph" ]
D. Lynden-Bell and J. Katz
astro-ph/9509155
Population synthesis of X-ray sources at the Galactic center
We model the evolution of the selected types of X-ray sources (both with BHs and NSs) for the star formation burst at the Galactic center. For the currently assumed starburst age of 4-7 millions years, our results are consistent with the recent {\it GRANAT} X-ray observations of the Galactic center and predict a substa...
1995-10-01
2007-05-23
[ "astro-ph" ]
S.B. Popov, V.M. Lipunov, L.M. Ozernoy, K.A. Postnov, and M.E. Prokhorov
astro-ph/9509154
Physics of the Very Early Universe
In this report of the workshop on `Physics of the Very Early Universe' held at GR14, the recent status and open problems in a selected number of major areas of interest are reviewed, focusing on attempts to develop a superstring cosmology and on progress in understanding current theories of structure formation.
1995-10-01
2007-05-23
[ "astro-ph", "gr-qc" ]
Robert H. Brandenberger (Brown University)
astro-ph/9509157
The life-cycle of star formation in distant clusters
We analyse the detailed distribution of star-forming and post-starburst members in three distant (z = 0.31) galaxy clusters in terms of evolutionary sequences that incorporate secondary bursts of star formation on pre-existing stellar populations. Using the number density of spectroscopically-confirmed members on the E...
1995-10-01
2015-06-24
[ "astro-ph" ]
A. J. Barger, A. Aragon-Salamanca, R. S. Ellis, W. J. Couch, I. Smail, and R. M. Sharples
astro-ph/9509156
The Nova-like Variables
We review optical observations and theoretical models of the non-magnetic nova-like variables (UX UMa, VY Scl and SW Sex stars). A brief discussion of the classification scheme is followed by a statistical overview of the observed properties. The most important features of each of the sub-classes are then reviewed, con...
1995-10-01
2016-01-27
[ "astro-ph" ]
V.S. Dhillon
astro-ph/9509153
NIR imaging and modeling of the core of M100
High-resolution NIR and optical images are used to constrain a dynamical model of the circumnuclear star forming (SF) region in the barred galaxy M100 (=NGC 4321). Subarcsecond resolution allowed us to distinguish important morphological details which are easily misinterpreted when using images at lower resolution. Sma...
1995-09-29
2019-07-31
[ "astro-ph" ]
J.H. Knapen (Montreal), R.F. Peletier (Kapteyn), I. Shlosman (Lexington), J.E. Beckman (IAC Tenerife), C.H. Heller (Goettingen), and R.S. de Jong (Durham)
astro-ph/9509150
A Simple Law for the Average Time History of Gamma-Ray Bursts and Their Time Dilations
Individual gamma ray bursts (GRBs) have very diverse time behavior - from a single pulse to a long complex sequence of chaotic pulses of different timescales. I studied light curves of GRBs using data from the CGRO's BATSE experiment and found that the average post-peak time history for a sample of 460 bursts obeys an ...
1995-09-29
2009-10-28
[ "astro-ph" ]
Boris E. Stern (Institute for Nuclear Research, Moscow, Russia, and Stockholm Observatory, Sweden)