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astro-ph/9308003
Fourier Analysis of Redshift Space Distortions and the Determination of Omega
The peculiar velocities of galaxies distort the pattern of galaxy clustering in redshift space, making the redshift space power spectrum anisotropic. In the linear regime, the strength of this distortion depends only on the ratio $\beta \equiv f(\Omega)/b \approx \Omega^{0.6}/b$, where $\Omega$ is the cosmological dens...
1993-08-04
2015-06-24
[ "astro-ph" ]
Shaun Cole, Karl B. Fisher and David H. Weinberg
astro-ph/9308001
Energy Principles for Self-Gravitating Barotropic Flows: II. the Stability of Maclaurin Flows
We analyze stability conditions of "Maclaurin flows" (self-gravitating, barotropic, two dimensional, stationary streams moving in closed loops around a point) by minimizing their energy, subject to fixing all the constants of the motion including mass and circulations. Necessary and sufficient conditions of stability a...
1993-08-04
2015-06-24
[ "astro-ph" ]
Asher Yahalom Joseph Katz and Shogo Inagaki
astro-ph/9308006
A Calculation of the Full Neutrino Phase Space in Cold+Hot Dark Matter Models
This paper presents a general-relativistic N-body technique for evolving the phase space distribution of massive neutrinos in linear perturbation theory. The method provides a much more accurate sampling of the neutrino phase space for the HDM initial conditions of N-body simulations in a cold+hot dark matter universe ...
1993-08-04
2009-10-22
[ "astro-ph" ]
Chung-Pei Ma and Edmund Bertschinger
astro-ph/9307040
Small Scale Microwave Background Fluctuations from Cosmic Strings
The Cosmic Microwave Background (CMB) fluctuations at very small angular scales (less than $10'$) induced by matter sources are computed in a simplified way. The result corrects a previous formula appearing in the literature. The small scale power spectrum from cosmic strings is then calculated by a new analytic method...
1993-07-30
2011-05-10
[ "astro-ph", "hep-ph" ]
Mark Hindmarsh
astro-ph/9307038
Evidence for Gaussian Initial Fluctuations from the 1.2 Jy IRAS Survey
We recover the one-point probability distribution function of the {\it initial} density fluctuations (\ipdf) from the quasi-linear galaxy density field of the 1.2 Jy \iras\ redshift survey smoothed by $10\hmpc$. The recovery, using the laminar, Eulerian, Zel'dovich approximation of Nusser and Dekel, is independent of $...
1993-07-29
2009-09-25
[ "astro-ph" ]
A. Nusser, A. Dekel, and A. Yahil
astro-ph/9307039
The Expected Dipole in the Distribution of Cosmological Gamma-Ray Bursts
If gamma-ray bursts originate at cosmological distances then their angular distribution should exhibit a dipole in the direction of the solar motion relative to the cosmic microwave background. This is due to the combined effects of abberation, an anisotropic shift of the burst event rate, and an angular variation in t...
1993-07-29
2009-10-22
[ "astro-ph" ]
Eyal Maoz
astro-ph/9307037
On the Distance Determination and Ionization of the High Velocity Clouds
We present a study of the ionization and thermal structure of neutral hydrogen clouds located in the Galactic halo, immersed in the extragalactic background radiation field, and supposed to be in pressure equilibrium with the surrounding (presumably) hot medium. The problem is solved numerically, but an useful analytic...
1993-07-28
2009-10-22
[ "astro-ph" ]
Andrea Ferrara & George B. Field
astro-ph/9307035
Recovering the Inflationary Potential
A procedure is developed for the recovery of the inflationary potential over the interval that affects astrophysical scales ($\approx 1\Mpc - 10^4\Mpc$). The amplitudes of the scalar and tensor metric perturbations and their power-spectrum indices, which can in principle be inferred from large-angle CBR anisotropy expe...
1993-07-26
2013-11-13
[ "astro-ph", "hep-ph" ]
M.S. Turner
astro-ph/9307036
Peculiar Velocity, Cosmic Perturbation Theory and the CMB Anisotropy
This is a somewhat extended version of the original July 93 report. It is proved that the cosmological density perturbation is associated with a peculiar velocity field. This allows a simple formulation of cosmological perturbation theory, which works entirely with quasi-Newtonian fluid flow equations. As an illustrati...
1993-07-26
2010-11-01
[ "astro-ph", "hep-ph" ]
Marco Bruni (School of Mathematical Sciences, Queen Mary and Westfield College, University of London, Mile End Road, London E1 4NS, UK., and Dipartimento di Astronomia, Universit\`a degli Studi di Trieste, via Tiepolo 11, 34131 Trieste, Italy) and David H. Lyth (School of Physics and Materials, Lancaster Univer...
astro-ph/9307034
Dynamics of Conductive/Cooling Fronts: Cloud Implosion and Thermal Solitons
We investigate the evolution of interfaces among phases of the interstellar medium with different temperature. It is found that, for some initial conditions, the dynamical effects related to conductive fronts are very important even if radiation losses, which tend to decelerate the front propagation, are taken into acc...
1993-07-23
2009-10-22
[ "astro-ph" ]
Andrea Ferrara & Yuri Shchekinov
astro-ph/9307030
Sequential Star Formation in Taurus Molecular Cloud 1
We discuss the fragmentation of a filamentary cloud on the basis of a 1-dimensional hydrodynamical simulation of a self-gravitating gas cloud. The simulation shows that dense cores are produced with a semi-regular interval in space and time from one edge to the other. At the initial stage the gas near one of the edges ...
1993-07-22
2009-10-22
[ "astro-ph" ]
Tomoyuki Hanawa, Satoshi Yamamoto and Yasuhiro Hirahara
astro-ph/9307033
Gravitational Instability of Cold Matter
We solve the nonlinear evolution of pressureless, irrotational density fluctuations in a perturbed Robertson-Walker spacetime using a new Lagrangian method based on the velocity gradient and gravity gradient tensors. Borrowing results from general relativity, we obtain a set of Newtonian ordinary differential equations...
1993-07-22
2009-10-22
[ "astro-ph", "gr-qc" ]
Edmund Bertschinger and Bhuvnesh Jain
astro-ph/9307032
Equilibrium, Stability and Orbital Evolution of Close Binary Systems
We present a new analytic study of the equilibrium and stability properties of close binary systems containing polytropic components. Our method is based on the use of ellipsoidal trial functions in an energy variational principle. We consider both synchronized and nonsynchronized systems, constructing the compressible...
1993-07-22
2009-10-22
[ "astro-ph" ]
D. Lai, F. A. Rasio, and S. L. Shapiro
astro-ph/9307031
The Quark-Hadron Phase Transition, QCD Lattice Calculations and Inhomogeneous Big-Bang Nucleosynthesis
We review recent lattice QCD results for the surface tension at the finite temperature quark-hadron phase transition and discuss their implications on the possible scale of inhomogeneities. In the quenched approximation the average distance between nucleating centers is smaller than the diffusion length of a protron, s...
1993-07-22
2009-10-22
[ "astro-ph", "hep-lat" ]
A.A. Coley and T. Trappenberg
astro-ph/9307029
Counter-Evolution of Faint Field Galaxies
We adopt a new approach to explore the puzzling nature of faint blue field galaxies. Instead of assuming that the local luminosity function is well defined, we first determine whether any non-evolving set of luminosity functions for different spectral types of galaxies is compatible with the observed marginal distribut...
1993-07-21
2009-10-22
[ "astro-ph" ]
D.C. Koo, C. Gronwall, and G. Bruzual
astro-ph/9307028
Hubble Space Telescope Images of the Subarcsecond Jet in DG Tau
We have applied a new restoration technique to archival [O~I], H$\alpha$, and continuum HST images of DG~Tau. The restored [O~I] and H$\alpha$ images show that DG~Tau has a jet with a projected length of 25~AU and width $\leq$10~AU, and is already collimated at a projected distance of $\sim$~40~AU (0\farcs25) from the ...
1993-07-17
2009-10-22
[ "astro-ph" ]
J. Kepner, P. Hartigan, C. Yang and S. Strom
astro-ph/9307027
Constraints on Neutrino Oscillations from Big Bang Nucleosynethesis
We discuss in detail the effect of neutrino oscillations in Big Bang nucleosynthesis, between active and sterile neutrinos, as well as between active and active neutrinos. We calculate the constraints on mixings between active and sterile neutrinos from the present observation of the primordial helium abundance and dis...
1993-07-16
2009-10-22
[ "astro-ph" ]
X. Shi, D. N. Schramm and B. D. Fields
astro-ph/9307024
Radio Transients from Gamma-Ray Bursters
The rapid time variability of gamma-ray bursts implies the sources are very compact, and the peak luminosities are so high that some matter must be ejected at ultra-relativistic speeds. The very large Lorentz factors of the bulk flow are also indicated by the very broad and hard spectra. It is natural to expect that wh...
1993-07-15
2016-08-30
[ "astro-ph" ]
Bohdan Paczynski and James E. Rhoads (Princeton University Observatory)
astro-ph/9307026
NGC 6397: A case study in the resolution of post-collapse globular cluster cores
Model surface brightness profiles based on Fokker-Planck simulations have been used to assess the high resolution surface brightness profile of the globular cluster NGC 6397 of Lauzeral et al. (1992). The profile is well fitted by the model in the maximum-expansion phase of a gravothermal oscillation with a core radius...
1993-07-15
2015-06-24
[ "astro-ph" ]
G. A. Drukier
astro-ph/9307025
Effect of Finite Nucleon Mass on Primordial Nucleosynthesis
We have modified the standard code for primordial nucleosynthesis to include the effect of finite nucleon mass on the weak-interaction rates as calculated by Seckel \cite{seckel}. We find a small, systematic increase in the $^4$He yield, $\Delta Y \simeq 0.0057\,Y$, which is insensitive to the value of the baryon-to-ph...
1993-07-15
2007-05-23
[ "astro-ph", "hep-ph" ]
Geza Gyuk and Michael S. Turner (Univ. of Chicago/Fermilab)
astro-ph/9307022
An imaging K-band survey - I: The catalogue, star and galaxy counts
We present results from a large area (552\,\sqamin) imaging $K$-band survey to a 5$\sigma$ limit of $K\simeq 17.3$. We have optical-infrared colours of almost all the objects in the sample. Star-galaxy discrimination is performed and the results used to derive the infrared star and galaxy counts. $K$-band ``no-evolutio...
1993-07-14
2015-06-24
[ "astro-ph" ]
Karl Glazebrook, J.A. Peacock, C.A. Collins and L. Miller
astro-ph/9307023
Masses of Multiquark Droplets
The mass formulae for finite lumps of strange quark matter with $u$, $d$ and $s$ quarks, and non-strange quark matter consisting of $u$ and $d$ quarks are derived in a non-relativistic potential model. The finite-size effects comprising the surface, curvature and even, the Gauss curvature were consistently obtained, wh...
1993-07-14
2009-10-22
[ "astro-ph" ]
L. Satpathy, P.K. Sahu and V.S. Uma Maheswari
astro-ph/9307021
The Infrared Tully-Fisher Relation in the Ursa-Major Cluster
We present new magnitudes derived from 1.65 micron images for 23 galaxies in the Ursa Major cluster. Magnitudes now exist for all but one spiral meeting our criteria for cluster membership and having HI velocity width greater than 187 km/s and inclination greater than 45 deg. These spirals fit a Tully-Fisher relation w...
1993-07-13
2009-10-22
[ "astro-ph" ]
R.F. Peletier and S.P. Willner
astro-ph/9307019
The radio background: radio-loud galaxies at high and low redshifts
The majority of this paper is devoted to discrete radio sources, and their consequences for cosmology. Three main issues are considered: (i) what makes a galaxy radio loud?; (ii) what do we know about how the population of radio-loud galaxies has changed with epoch?; and (iii) what can observations of high-redshift rad...
1993-07-12
2007-05-23
[ "astro-ph" ]
John Peacock (Royal Observatory Edinburgh)
astro-ph/9307020
The Inflationary Energy Scale
The energy scale of inflation is of much interest, as it suggests the scale of grand unified physics and also governs whether cosmological events such as topological defect formation can occur after inflation. The COBE results are used to limit the energy scale of inflation at around 60 $e$-foldings from the end of inf...
1993-07-12
2010-11-01
[ "astro-ph", "gr-qc" ]
Andrew R Liddle
astro-ph/9307018
Did the universe recombine? New spectral constraints on reheating
One still cannot conclusively assert that the universe underwent a neutral phase, despite the new COBE FIRAS limit y<0.000025 on Compton y-distortions of the cosmic microwave background. Although scenarios where the very early (z=1000) ionization is thermal, caused by IGM temperatures exceeding 10000K, are clearly rule...
1993-07-09
2009-10-07
[ "astro-ph" ]
Max Tegmark, Joseph Silk
astro-ph/9307017
On the inevitability of reionization: implications for cosmic microwave background fluctuations
Early photoionization of the intergalactic medium is discussed in a nearly model-independent way, in order to investigate whether early structures corresponding to rare Gaussian peaks in a CDM model can photoionize the intergalactic medium sufficiently early to appreciably smooth out the microwave background fluctuatio...
1993-07-09
2009-10-07
[ "astro-ph" ]
Max Tegmark, Joseph Silk, Alain Blanchard
astro-ph/9307016
Classical and Quantum Theory of Perturbations in Inflationary Universe Models
A brief introduction to the gauge invariant classical and quantum theory of cosmological perturbations is given. The formalism is applied to inflationary Universe models and yields a consistent and unified description of the generation and evolution of fluctuations. A general formula for the amplitude of cosmological p...
1993-07-09
2007-05-23
[ "astro-ph", "hep-ph" ]
R. Brandenberger (Brown Univ.), H. Feldman (Univ. of Michigan) and V. Mukhanov (ETH Zuerich)
astro-ph/9307014
Evidence for the Galactic Origin of Gamma-Ray Bursts
We investigate the angular distribution of the $\gamma$-ray bursts in the publicly available BATSE catalogue, using the measures of burst brightness $B$ and short time scale ($\simless$ 0.3 s) variability $V$ which we introduced earlier. We show that the 54 type I ($\log V \le -0.8$) bursts lying in the middle brightne...
1993-07-08
2016-06-08
[ "astro-ph" ]
J.M. Quashnock and D.Q. Lamb
astro-ph/9307015
Evidence That Gamma-Ray Burst Sources Repeat
We investigate clustering in the angular distribution of the 260 $\gamma$-ray bursts in the publicly available BATSE catalogue, using a nearest neighbour analysis and the measures of burst brightness $B$ and short time scale variability $V$ which we introduced earlier. We find that while all 260 bursts are only modestl...
1993-07-08
2016-06-08
[ "astro-ph" ]
J.M. Quashnock and D.Q. Lamb
astro-ph/9307013
Solar Neutrino Experiments: New Physics?
Physics beyond the simplest version of the standard electroweak model is required to reconcile the results of the chlorine and the Kamiokande solar neutrino experiments. None of the 1000 solar models in a full Monte Carlo simulation is consistent with the results of the chlorine or the Kamiokande experiments. Even if t...
1993-07-07
2009-09-25
[ "astro-ph" ]
John N. Bahcall
astro-ph/9307012
Geometry of the HST Planetary Camera Field
We present a solution for the relative positions and orientations of the four CCD chips on the Hubble Space Telescope (HST) Planetary Camera (PC). An accurate solution is required when matching HST images with ground-based images or with one another. The solution is accurate to about 1/4 PC pixel or about $0{.\hskip-2p...
1993-07-06
2009-10-22
[ "astro-ph" ]
Andrew Gould and Brian Yanny
astro-ph/9307007
CBS - a Program for Close Binary System Light Curve Analysis
CBS is a new program for binary system light curve analysis, it generates synthetic light curves for a binary system, accounting for eclipses, tidal distortion, limb darkening, gravity darkening and reflection; it is also possible to compute the light contribution and eclipses of an accretion disk. The bolometric light...
1993-07-05
2007-05-23
[ "astro-ph" ]
Loretta Solmi and Marcello Galli
astro-ph/9307010
Sharp Hi Edges in the Outskirts of Disk Galaxies
Observations indicate that some extended outer disks have a sharp cut off in the surface density of neutral hydrogen when this approaches the value of $\sim 2\times 10^{19}$ cm$^{-2}$. In this paper we model these HI edges as places where the ratio of neutral to ionized hydrogen drops rapidly due to ionizing radiation....
1993-07-05
2009-10-22
[ "astro-ph" ]
Edvige Corbelli and Edwin E. Salpeter
astro-ph/9307006
The Local Galaxy Density and the Arm Class of Spiral Galaxies
We have examined the effect of the environmental density on the arm classification of an extensive sample of spiral galaxies included in the Nearby Galaxy Catalog (Tully, 1988a). We have also explored the dependence of the arm class of a galaxy on other factors, such as its blue absolute magnitude and its disk-to-total...
1993-07-05
2009-10-22
[ "astro-ph" ]
G. Giuricin, P. Monaco, F. Mardirossian, M. Mezzetti
astro-ph/9307005
The Environment of Lyman a Absorbers in the Sightline toward 3C273
We present new ground-based data following up on the HST discovery of low-redshift Lya absorption in the sight-line to the quasar 3C273. Narrow-band filter observations show that there are no H II regions within a 12 kpc radius of the line-of-sight to the quasar, at the velocities of three of the absorbers. Broad-band ...
1993-07-05
2009-10-22
[ "astro-ph" ]
S. L. Morris, R. J. Weymann, Alan Dressler, P. J. McCarthy, B. A. Smith, R. J. Terrile, R. Gionvanelli and M. Irwin
astro-ph/9307011
Exteremely High Velocity Outflows
Extremely high velocity (EHV) wings, with full widths of 72 to 140 km/s, are seen on the CO J=3-2 lines toward W3 IRS 5, GL 490, NGC 2071, W28 A2, GL 2591, S140, and Cepheus A. The results of our survey suggest that EHV wings are common around infrared sources of moderate to high luminosity (500 to 4x10^5 Lsun) in de...
1993-07-05
2009-10-22
[ "astro-ph" ]
Minho Choi, Neal J. Evans II, and Daniel T. Jaffe
astro-ph/9307009
Hi Spin Temperatures and Heating Requirements in Outer Regions of Disk Galaxies
ABSRACT:We show how to use 21-cm emission and absorption studies to estimate the heat inputs to the neutral gas in low pressure environments, such as in outer disks of spiral galaxies, in galactic halos or in intergalactic space. For a range of model parameters we calculate the gas kinetic and spin temperatures ($T_K$ ...
1993-07-05
2009-10-22
[ "astro-ph" ]
Edvige Corbelli and Edwin E. Salpeter
astro-ph/9307008
Neutral Hydrogen Absorption and Emission in the Quasar/Galaxy Pair 3C275.1/\NGC4651
3C275.1 and \NGC4651 make a particularly interesting quasar/galaxy pairing because of the alignment of such a strong radio emitter behind the outer H\I disk of a relatively undisturbed spiral galaxy. This provides an opportunity to study the spin-temperature characteristics of atomic hydrogen at low column densities, i...
1993-07-05
2009-10-22
[ "astro-ph" ]
Stephen E. Schneider and Edvige Corbelli
astro-ph/9307003
Linear Potentials and Galactic Rotation Curves - Representative Fitting
We present a simple, closed form expression for the potential of an axisymmetric disk of stars interacting through gravitational potentials of the form $V(r)=-\beta /r+\gamma r/2$, the potential associated with fundamental sources in the conformal invariant fourth order theory of gravity which has recently been advance...
1993-07-02
2007-05-23
[ "astro-ph", "gr-qc", "hep-ph" ]
Philip D. Mannheim (University of Connecticut)
astro-ph/9307004
Linear Potentials and Galactic Rotation Curves - Formalism
In the first paper in this series we presented a typical set of galactic rotation curves associated with the conformal invariant fourth order theory of gravity which has recently been advanced by Mannheim and Kazanas as a candidate alternative to the standard second order Einstein theory. Reasonable agreement with data...
1993-07-02
2007-05-23
[ "astro-ph", "gr-qc", "hep-ph" ]
Philip D. Mannheim (University of Connecticut)
astro-ph/9307001
Clustering in the 1.2 Jy IRAS Galaxy Redshift Survey I: The Redshift and Real Space Correlation Functions
We present analyses of the two-point correlation function derived from an all-sky redshift survey of 5313 galaxies extracted from the Infrared Astronomical Satellite (IRAS) database. The redshift space correlation function \xi(s) is well described by a power law, $\xi(s) = (s/4.53h^{-1}{\rm Mpc})^{-1.28}$, on scales \s...
1993-07-01
2015-06-24
[ "astro-ph" ]
Karl B. Fisher, Marc Davis, Michael A. Strauss, Amos Yahil, and John Huchra
astro-ph/9307002
Hybrid Inflation
Usually inflation ends either by a slow rolling of the inflaton field, which gradually becomes faster and faster, or by a first-order phase transition. We describe a model where inflation ends in a different way, due to a very rapid rolling (`waterfall') of a scalar field $\sigma$ triggered by another scalar field $\ph...
1993-07-01
2009-09-29
[ "astro-ph", "gr-qc" ]
Andrei Linde
astro-ph/9306030
Extended Inflation with a Curvature-Coupled Inflaton
We examine extended inflation models enhanced by the addition of a coupling between the inflaton field and the space-time curvature. We examine two types of model, where the underlying inflaton potential takes on second-order and first-order form respectively. One aim is to provide models which satisfy the solar system...
1993-06-30
2009-10-22
[ "astro-ph", "gr-qc" ]
Andrew M Laycock and Andrew R Liddle
astro-ph/9306029
Tensor Perturbations in Inflationary Models as a Probe of Cosmology
In principle, the tensor metric (gravity-wave) perturbations that arise in inflationary models can, beyond probing the underlying inflationary model, provide information about the Universe: ionization history, presence of a cosmological constant, and epoch of matter-radiation equality. Because tensor perturbations give...
1993-06-30
2009-08-18
[ "astro-ph", "hep-ph" ]
Michael S. Turner, Martin White, and James E. Lidsey
astro-ph/9306028
Collapse and Fragmentation of Magnetized Cylindrical Clouds
Gravitational collapse of the cylindrical elongated cloud is studied by numerical magnetohydrodynamical simulations. In the infinitely long cloud in hydrostatic configuration, small perturbations grow by the gravitational instability. The most unstable mode indicated by a linear perturbation theory grows selectively ev...
1993-06-29
2009-10-22
[ "astro-ph" ]
Kohji Tomisaka (Niigata University, Niigata, Japan)
astro-ph/9306026
N-Body Simulations of Star-Disc Captures in Globular Clusters
The presence of protostellar disks can greatly increase the dissipation during close stellar encounters, leading to the formation of a significant population of binaries during the initial collapse and virialization of a cluster. We have used N-body simulations of collapsing globular clusters to find the major factors ...
1993-06-25
2015-06-24
[ "astro-ph" ]
S. D. Murray and C. J. Clarke (Institute of Astronomy, Madingley Road, Cambridge CB3 0HA, U.K.)
astro-ph/9306027
Polarization of the Microwave Background due to Primordial Gravitational Waves
The contribution of gravitational wave (tensor metric) and energy density (scalar metric) fluctuations to the cosmic microwave background polarization is computed by numerically solving the relativistic radiation transfer equations. We find that the tensor contribution is significant only at large angular scales (multi...
1993-06-25
2009-10-22
[ "astro-ph", "gr-qc" ]
Robert Crittenden, Richard L. Davis, and Paul J. Steinhardt
astro-ph/9306025
Nonlinear Instabilities in Shock-Bounded Slabs
(substantial changes to section 3.2, otherwise minor) We present an analysis of the hydrodynamic stability of a cold slab bounded by two accretion shocks. Previous numerical work has shown that when the Mach number of the shock is large the slab is unstable. Here we show that to linear order both the bending and breath...
1993-06-24
2009-10-22
[ "astro-ph" ]
ET Vishniac
astro-ph/9306024
Vacuum-Polarization Corrections to Solar-Fusion Rates
The vacuum-polarization corrections to rates for nuclear-fusion reactions in the $pp$ chain and in the CNO cycle are calculated. For the reactions of particular importance to the solar-neutrino problem, the $\Hethree$, $\Hefour$, $\Be$, and $\Ni$ reactions, we find the magnitude of the effect to be less than 2\%. The e...
1993-06-24
2008-11-26
[ "astro-ph", "hep-ph", "nucl-th" ]
Marc Kamionkowski and John N. Bahcall
astro-ph/9306022
The emission spectra of radioweak quasars. I. The farinfrared emission
We model farinfrared (FIR) spectra of radioweak quasars with the assumption that the emission is from heated dust, and that the heating is due to the central engine via energetic particles. These energetic particles are diffusing from a postulated source near the central engine through a tenuous galactic halo to arrive...
1993-06-23
2007-05-23
[ "astro-ph" ]
Martina Niemeyer and Peter L. Biermann (Max-Planck-Institut f"ur Radioastronomie Bonn)
astro-ph/9306023
Dynamics of the Globular Cluster NGC 362
In this paper we have examined the internal dynamics of the globular cluster NGC 362. A V band surface brightness profile (SBP) was constructed from CCD images, and, after it was determined that the cluster is not post core-collapse, fit with single- and multi-mass King-Michie (KM) models. The total cluster luminosity ...
1993-06-23
2009-10-22
[ "astro-ph" ]
P. Fischer, D.L. Welch, M. Mateo and P. C\^ot\'e
astro-ph/9306021
Late reionization by supernova-driven winds
A model is presented in which supernova-driven winds from early galaxies reionize the intergalactic medium by z=5. This scenario can explain the observed absence of a Gunn-Peterson trough in the spectra of high-redshift quasars providing that the bulk of these early galaxies are quite small, no more massive than about ...
1993-06-23
2009-10-07
[ "astro-ph" ]
Max Tegmark, Joseph Silk, August Evrard
astro-ph/9306020
Weakly Damped Modes in Star Clusters and Galaxies
A perturber may excite a coherent mode in a star cluster or galaxy. If the stellar system is stable, it is commonly assumed that such a mode will be strongly damped and therefore of little practical consequence other than redistributing momentum and energy deposited by the perturber. This paper demonstrates that this a...
1993-06-22
2009-10-22
[ "astro-ph" ]
Martin D. Weinberg
astro-ph/9306019
Almost Readily Detectable Time Delays from Gravity Waves?
When a source of gravity waves is conveniently placed between the Earth and some source of light, preferably a pulsating source, the magnitude of time delays induced by the gravity waves could, in optimal situations, be not too far out of the reach of already existing technology. Besides the odd case of near-to-perfect...
1993-06-21
2010-11-01
[ "astro-ph", "gr-qc" ]
Redouane Fakir
astro-ph/9306018
The Three-point Function as a Probe of Models for Large-scale Structure
We analyze the consequences of models of structure formation for higher-order ($n$-point) galaxy correlation functions in the mildly non-linear regime. Several variations of the standard $\Omega=1$ cold dark matter model with scale-invariant primordial perturbations have recently been introduced to obtain more power on...
1993-06-20
2016-08-30
[ "astro-ph" ]
Joshua A. Frieman and Enrique Gaztanaga
astro-ph/9306017
A Self-Consistent Model For The Long-Term Gamma-Ray Spectral Variability of Cygnus X-1
The long-term transitions of the black hole candidate Cygnus X-1 (between the states gamma_1, gamma_2, and gamma_3) include the occasional appearance of a strong ~ MeV bump (gamma_1), whose strength appears to be anti-correlated with the continuum flux (~ 400 keV) due to the Compton upscattering of cold disk photons by...
1993-06-19
2009-10-22
[ "astro-ph", "gr-qc" ]
Fulvio Melia & Ranjeev Misra
astro-ph/9306015
Star Clusters
This review concentrates almost entirely on globular star clusters. It emphasises the increasing realisation that few of the traditional problems of star cluster astronomy can be studied in isolation: the influence of the Galaxy affects dynamical evolution deep in the core, and the spectrum of stellar masses; in turn t...
1993-06-18
2016-01-27
[ "astro-ph" ]
Douglas C. Heggie (University of Edinburgh, Department of Mathematics and Statistics, King's Buildings, Edinburgh EH9 3JZ, U.K.)
astro-ph/9306016
Focusing of Alfvenic Power in the Context of Gamma-Ray Burst Emissivity
Highly dynamic magnetospheric perturbations in neutron star environments can naturally account for the features observed in Gamma-ray Burst spectra. The source distribution, however, appears to be extragalactic. Although noncatastrophic isotropic emission mechanisms may be ruled out on energetic and timing arguments, M...
1993-06-18
2009-10-22
[ "astro-ph" ]
M. Fatuzzo and F. Melia
astro-ph/9306014
Neutrino Balls and Gamma-Ray Bursts
We propose a mechanism by which the neutrino emission from a supernova-type explosion can be converted into a gamma-ray burst of total energy $\sim 10^{50}$ ergs. This occurs naturally if the explosion is situated inside a ball of trapped neutrinos, which in turn may lie at a galactic core. There are possible unique si...
1993-06-17
2009-10-22
[ "astro-ph", "hep-ph" ]
B. Holdom and R. A. Malaney
astro-ph/9306013
The Extended 12 Micron Galaxy Sample
We have selected an all--sky sample of 893 galaxies from the IRAS FSC--2, defined by a total (ADDSCAN) 12um flux limit of 0.22~Jy. Completeness is verified to 0.30~Jy, below which we have quantified the incompleteness down to 0.22~Jy for our statistical analysis. \P The Seyfert subsample is the largest unbiased sample ...
1993-06-17
2009-10-22
[ "astro-ph" ]
B. Rush, M. A. Malkan, and L. Spinoglio
astro-ph/9306012
Cosmic Variance of the Three-Point Correlation Function of the Cosmic Microwave Background
The fluctuations in the cosmic microwave background radiation may contain deviations from gaussian statistics which would be reflected in a nonzero value of three-point correlation function of $\Delta T$. However, any potential observation of the three-point function is limited by cosmic variance, even if a whole-sky m...
1993-06-15
2009-10-22
[ "astro-ph", "hep-ph" ]
Mark Srednicki
astro-ph/9306009
Inhomogeneous Inflation: Numerical Evolution
We describe our 3-dimensional numerical relativity code for the evolution of inhomogeneous cosmologies. During the evolution the constraint equations are monitored but not solved. The code has been tested against perturbation theory with good results. We present some runs of inhomogeneous inflation with strongly inhomo...
1993-06-15
2009-10-22
[ "astro-ph", "hep-ph" ]
Hannu Kurki-Suonio, Pablo Laguna, and Richard A. Matzner
astro-ph/9306010
Reconstruction Analysis I.: Redshift--space deprojection in the quasi--nonlinear regime
We present a new method for extracting the true 3-d velocity and density fields from the nonlinear redshift--space projected density field. The method is based on the nonlinear, nonlocal transformation of the density field. We assume a curl--free velocity field, although in the formulation presented here this assumptio...
1993-06-15
2015-06-24
[ "astro-ph" ]
A.N. Taylor & M. Rowan-Robinson
astro-ph/9306011
Evidence for Two Distinct Morphological Classes of Gamma-Ray Bursts from their Short Timescale Variability
We have analyzed the 241 bursts for which peak counts $\C$ exist in the publicly available Burst and Transient Source Experiment (BATSE) catalog. Introducing peak counts in 1024 ms as a measure of burst brightness $\B$ and the ratio of peak counts in 64 and 1024 ms as a measure of short timescale variability $\V$, we f...
1993-06-15
2009-10-22
[ "astro-ph" ]
D. Q. Lamb, C. Graziani, and I. A. Smith
astro-ph/9306008
On the Lyman-alpha Emission of Starburst Galaxies
Nearby starburst galaxies have consistently shown anomalous Ly-alpha/H-beta ratios. By re-analysing the published IUE/optical observations, we show that most starbursts present a normal Ly-alpha emission, consistent with case B recombination theory, provided extinction laws appropriate to their metallicities are used. ...
1993-06-13
2009-10-22
[ "astro-ph" ]
David Valls-Gabaud
astro-ph/9306007
Polarized Scattering in the Vicinty of Galaxies
Some bright cD galaxies in cluster cooling flows have Thomson optical depths exceeding 0.01. A few percent of their luminosity is scattered and appears as diffuse polarized emission. We calculate the scattering process for different geometric combinations of luminosity sources and scattering media. We apply our results...
1993-06-11
2009-10-22
[ "astro-ph" ]
B.W. Murphy and D.F. Chernoff
astro-ph/9306005
Gamma Rays and Neutrinos from a Powerful Cosmic Accelerator
Recent measurements of gamma rays from the powerful quasar 3C273 by the Compton Gamma Ray Observatory show that a powerful cosmic accelerator must be operating. In this paper the evidence for proton acceleration is collected with the result that (i) the gamma ray spectrum should flatten slightly above a few GeV and tha...
1993-06-11
2009-10-22
[ "astro-ph" ]
Karl Mannheim
astro-ph/9306006
Cosmic Voids and Biased Galaxy Formation
Using cosmological $N$-body simulations and the void probability function (VPF), we investigate the statistical properties of voids within a wide range of initially Gaussian models for the origin of large-scale structure. We pay particular attention to the ability of the VPF to diagnose `biased galaxy formation': the p...
1993-06-11
2015-06-24
[ "astro-ph" ]
Blane Little, David H. Weinberg
astro-ph/9306004
An Upper Limit to the Mass of Black Holes in the Halo of our Galaxy
If massive black holes constitute the dark matter in the halo surrounding the Milky Way, the existence of low mass globular clusters in the halo suggests an upper limit to their mass, $M_{_{BH}}$. We use a combination of the impulse approximation and numerical simulations to constrain $M_{_{BH}} \lsim 10^3M_\odot$, oth...
1993-06-10
2009-10-22
[ "astro-ph" ]
Ben Moore
astro-ph/9306003
Skewness Induced by Gravity
Large-scale structures, observed today, are generally believed to have grown from random, small-amplitude inhomogeneities, present in the early Universe. We investigate how gravitational instability drives the distribution of these fluctuations away from the initial state, assumed to be Gaussian. Using second order per...
1993-06-08
2009-10-22
[ "astro-ph" ]
R. Juszkiewicz, F. R. Bouchet and S. Colombi
astro-ph/9306002
Look Back Time, the Age of the Universe, and the Case for a Positive Cosmological Constant
We present explicit expressions for the calculation of cosmological look back time, for zero cosmological constant and arbitrary density parameter $\Omega$, which, in the limit as redshift becomes infinite, give the age of the universe. The case for non-zero cosmological constant is most easily solved via numerical int...
1993-06-07
2007-05-23
[ "astro-ph" ]
Kevin Krisciunas (Joint Astronomy Centre, Hilo, Hawaii, USA)
astro-ph/9306001
Did Cosmic Rays Reionize the Intergalactic Medium?
We investigate the role of cosmic rays from young galaxies in heating and ionizing the intergalactic medium (IGM) at high redshift. Using the IRAS observations at $60 \mu m$, we estimate the cosmic ray luminosity density at the present epoch. We consider various forms of luminosity evolution in redshift and calculate (...
1993-06-02
2015-06-24
[ "astro-ph" ]
Biman B. Nath, Peter L. Biermann
astro-ph/9305038
Reionization and cosmic microwave background distortions: a complete treatment of second order Compton scattering
The ionization history of the universe provides a major source of ambiguity in constraining cosmological models using small angular scale microwave background anisotropies. To clarify these issues, we consider a complete treatment of Compton scattering to second order, an approach which may be applicable to other astro...
1993-05-29
2009-10-22
[ "astro-ph" ]
Wayne Hu, Douglas Scott & Joseph Silk
astro-ph/9305036
Strange Cases from the Files of Astronomical Sociology
What astronomer could not use his own surname because his father was beheaded for sorcery? Who built the only observatory worth $5 billion in today's money? Who had worse luck than YOU travelling thousands of miles NOT to observe an astronomical event? Who had one of his books bound in human skin at the request of his ...
1993-05-28
2007-05-23
[ "astro-ph" ]
Kevin Krisciunas
astro-ph/9305037
The gamma-ray visibility of supernova remnants: a test of cosmic ray origin
Gamma ray production in supernova remnants is discussed on the basis of current ideas about cosmic ray acceleration.
1993-05-28
2007-05-23
[ "astro-ph" ]
L O'C Drury, F A Aharonian and H J Voelk
astro-ph/9305035
Motion of a Solar Mass Compact Object Around a Massive Rotating Black Hole
This preprint is based on two articles accepted by MNRAS and ApJ. Our aim is to study the evolution of the orbit of a star under the influence of interactions with an accretion disc in an AGN. The model considered consists of a low-mass compact object orbiting a supermassive black hole and colliding periodically with...
1993-05-27
2007-05-23
[ "astro-ph" ]
V. Karas and D. Vokrouhlicky
astro-ph/9305034
Sinusoidal Gravitational Waves from the Nuclei of Active Galaxies
It is believed that most quasars and galaxies present two common features: the presence in their core of a supermassive object, and the experience of one or more encounters with other galaxies. In this scenario, it is likely that a substantial fraction of active galactic nuclei harbour a supermassive binary, fueled by ...
1993-05-26
2007-05-23
[ "astro-ph", "gr-qc" ]
Giacomo Giampieri
astro-ph/9305032
Redshift distortions of galaxy correlation functions
To examine how peculiar velocities can affect the 2-, 3-, and 4-point redshift correlation functions, we evaluate volume-average correlations for configurations that emphasize and minimize redshift distortions for four different volume-limited samples from each of the CfA, SSRS, and IRAS redshift catalogs. We find a ch...
1993-05-26
2008-11-26
[ "astro-ph" ]
J.N.Fry and Enrique Gaztanaga
astro-ph/9305033
Comparing Direct N-Body Integration with Anisotropic Gaseous Models of Star Clusters
We compare the results for the dynamical evolution of star clusters derived from anisotropic gaseous models with the data from N-body simulations of isolated and one-component systems, each having modest number of stars. The statistical quality of N-body data was improved by averaging results from many N-body runs, eac...
1993-05-26
2015-06-24
[ "astro-ph" ]
Mirek Giersz and Rainer Spurzem
astro-ph/9305031
Galaxy Redshifts: Improved Techniques
This paper analyses the effects of random noise in determining errors and confidence levels for galaxy redshifts obtained by cross-correlation techniques. The main finding is that confidence levels have previously been overestimated, and errors inaccurately calculated in certain applications. New formul\ae\ are present...
1993-05-25
2015-06-24
[ "astro-ph" ]
A.F. Heavens
astro-ph/9305030
"Sample Variance" in Small-Scale CMB Anisotropy Experiments
We discuss the effects of finite sky coverage and the uncertainty in extracting information about the power spectrum from experiments on small angular scales. In general the cosmic variance is enhanced by a factor of $4\pi/A$, where $A$ is the solid angle sampled by the experiment. As a rough guide, an experiment with ...
1993-05-25
2009-10-22
[ "astro-ph", "hep-ph" ]
Douglas Scott, Mark Srednicki, Martin White
astro-ph/9305029
The Sensitivity of Ligo to a Stochastic Background, and its Dependance on the Detector Orientations
We analyze the sensitivity of a network of interferometer gravitational-wave detectors to the gravitational-wave stochastic background, and derive the dependence of this sensitivity on the orientations of the detector arms. We build on and extend the recent work of Christensen, but our conclusion for the optimal choice...
1993-05-24
2009-12-30
[ "astro-ph", "gr-qc" ]
Eanna Flanagan
astro-ph/9405049
Complete normality conditions for the dynamical systems on Riemannian manifolds
New additional equations for the Newtonian dynamical systems on Riemannian manifolds are found. They supplement the previously found weak normality conditions up to the complete normality conditions for Newtonian dynamical systems.
1993-05-24
2007-05-23
[ "astro-ph" ]
A.Yu. Boldin, A.A. Bronnikov, V.V. Dmitrieva, R.A. Sharipov (Bashkir State University, Ufa, Russia)
astro-ph/9305028
Lectures on Modern Cosmology and Structure Formation
Focus of these lectures is the challenge of explaining the origin of structure in the Universe. The interplay between quantum field theory and classical general relativity has given rise to several interesting cosmological models which contain mechanisms for generating density inhomogeneities. The three theories discus...
1993-05-22
2007-05-23
[ "astro-ph", "hep-ph" ]
O. Eboli and V. Ribelles
astro-ph/9305027
The Orbit of the Binary Star Delta Scorpii
Although delta Scorpii is a bright and well-studied star, the details of its multiplicity have remained unclear. Here we present the first diffraction-limited image of this 0.12 arcsec binary star, made using optical interferometry, and resolve the confusion that has existed in the literature over its multiplicity. E...
1993-05-22
2009-10-22
[ "astro-ph" ]
Timothy R. Bedding
astro-ph/9305026
The Ultraviolet Emission Properties of Five Low-Redshift Active Galactic Nuclei at High Signal to Noise and Spectral Resolution
We analyze the ultraviolet (UV) emission line and continuum properties of five low-redshift active galactic nuclei (four luminous quasars: PKS~0405$-$123, H1821+643, PG~0953+414, and 3C273, and one bright Seyfert 1 galaxy: Mrk~205). The HST spectra have higher signal-to-noise ratios (typically $\sim 60$ per resolution ...
1993-05-21
2011-02-19
[ "astro-ph" ]
Ari Laor, John N. Bahcall, Buell T. Jannuzi, Donald P. Schneider (IAS), Richard F. Green (NOAO), George F. Hartig (STScI)
astro-ph/9305025
Lick Slit Spectra of Thirty-Eight Objective Prism QSO Candidates and Low Metallicity Halo Stars
We present Lick Observatory slit spectra of 38 objects which were claimed to have pronounced ultraviolet excess and emission lines by Zhan \& Chen. Most of our spectra have FWHM spectral resolutions of about 4~\AA , and relatively high S/N of about 10 -- 50, although some have FWHM $\simeq 15$~\AA ~or lower S/N. We fin...
1993-05-19
2009-10-22
[ "astro-ph" ]
D. Tytler, X.-M Fan, V.T. Junkkarinen and R.D. Cohen
astro-ph/9305023
AG Carinae III. The 1990 hot phase of the star and the physical structure of the circumstellar environment
Long slit spectra of the region around the Luminous Blue Variable AG Car obtained in June 1990, just before the onset of its new brightening phase, indicate that AG Car was in the hottest phase so far recorded. The spectrum shows strong broad emissions of He II 468.6 nm, and [Fe III] 465.8-470.1 nm, and He I, N II, Si ...
1993-05-19
2011-05-23
[ "astro-ph" ]
R. Viotti, V.F. Polcaro, C. Rossi
astro-ph/9305024
A forgotten episode of the $\eta ~Car$ light curve in 1860-1865
We have found previously unreported observations of the galactic Luminous Blue Variable $\eta ~Car$ covering the period 1860-1865. Contrary to the current belief, these data suggest that the star reached the first magnitude in 1860-1862, with possible large luminosity fluctuations, followed by a steep fading in 1865. A...
1993-05-19
2011-05-23
[ "astro-ph" ]
V.F. Polcaro and R. Viotti
astro-ph/9305021
Hydrodynamic Detonation Instability in Electroweak and QCD Phase Transitions
The hydrodynamic stability of deflagration and detonation bubbles for a first order electroweak and QCD phase transition has been discussed recently with the suggestion that detonations are stable. We examine here the case of a detonation more carefully. We find that in front of the bubble wall perturbations do not gro...
1993-05-18
2009-10-22
[ "astro-ph" ]
Mark Abney
astro-ph/9305022
A Measurement of the Medium-Scale Anisotropy in the Cosmic Microwave Background Radiation
Observations from the first flight of the Medium Scale Anisotropy Measurement (MSAM) are analyzed to place limits on Gaussian fluctuations in the Cosmic Microwave Background Radiation (CMBR). This instrument chops a 30\arcmin\ beam in a 3 position pattern with a throw of $\pm40\arcmin$; the resulting data is analyzed i...
1993-05-18
2009-10-22
[ "astro-ph" ]
E. S. Cheng, D. A. Cottingham, D. J. Fixsen, C. A. Inman, M. S. Kowitt, S. S. Meyer, L. A. Page, J. L. Puchalla, and R. F. Silverberg
astro-ph/9305020
The Rate of the Proton-Proton Reaction
We re-evaluate the matrix element for the proton-proton reaction which is important for stellar-evolution calculations and for the solar-neutrino problem. We self-consistently determine the effect of vacuum polarization on the matrix element by first correcting the low-energy scattering data to account for vacuum polar...
1993-05-17
2009-10-22
[ "astro-ph", "hep-ph", "nucl-th" ]
Marc Kamionkowski and John N. Bahcall
astro-ph/9305018
Moments of the Counts Distribution in the 1.2 Jy IRAS Redshift Survey
We derive the volume-averaged 2, 3, 4, and 5-point correlation functions from the moments of the Count probability distribution function of a redshift survey of IRAS galaxies, and find them all to be reasonably well-described by power laws. Weak systematic effects with the sample size provide evidence for stronger clus...
1993-05-14
2009-10-22
[ "astro-ph" ]
Francois R. Bouchet, et al
astro-ph/9305019
Limits on the Primordial Fluctuation Spectrum Void Sizes and CMBR Anisotropy
We suggest to use the common appearance of voids with a scale of $5000 \kms$ in the galaxy distribution to estimate the power spectrum on this scale. We use a simple model for a gravitational formation of voids and we compare the results with the matter fluctuations as constrained by the CMBR observations of COBE. We f...
1993-05-14
2008-02-03
[ "astro-ph" ]
T. Piran, M. Lecar, D. S. Goldwirth, L. Nicolaci da Costa, and G. R. Blumenthal
astro-ph/9305017
High resolution kinematics of galactic globular clusters. II. On the significance of velocity dispersion measurements
Small number statistics may heavily affect the structure of the broadening function in integrated spectra of galactic globular cluster centers. As a consequence, it is a priori unknown how closely line broadening measure- ments gauge the intrinsic velocity dispersions at the cores of these stel- lar systems. We have ta...
1993-05-13
2007-05-23
[ "astro-ph" ]
Simone R. Zaggia, Massimo Capaccioli, and Giampaolo Piotto
astro-ph/9305014
Charged Boson Stars and Vacuum Instabilities
We consider charged boson stars and study their effect on the structure of the vacuum. For very compact particle like ``stars", with constituent mass $m_{*}$ close to the Planck mass $m_{Pl}$, i.e. $m_{*}^{2} = {\cal O} (\alpha m_{Pl}^{2})$, we argue that there is a limiting total electric charge $Z_c$, which, primaril...
1993-05-12
2019-08-17
[ "astro-ph", "gr-qc" ]
P.Jetzer, P.Liljenberg, B.-S.Skagerstam
astro-ph/9305015
Gravitational Waves and $\gamma$-Ray Bursts
Coalescing binaries in distant galaxies are one of the most promising sources of gravitational waves detectable by the LIGO project.$^{[1-5]}$ They are also a copious source of neutrinos,$^{[1]}$ however these neutrino pulses are far too weak to be detected on earth. Several years ago Eichler \etal$\,$$^{[6]}$ suggeste...
1993-05-12
2009-10-22
[ "astro-ph", "gr-qc" ]
Christopher S. Kochanek and Tsvi Piran
astro-ph/9305011
Structure Formation with Cold + Hot Dark Matter
We report results from high-resolution particle-mesh (PM) N-body simulations of structure formation in an $\Omega=1$ cosmological model with a mixture of Cold plus Hot Dark Matter (C+HDM) having $\Omega_{\rm cold}=0.6$, $\Omega_\nu=0.3$, and $\Omega_{\rm baryon}=0.1$. We present analytic fits to the C+HDM power spectra...
1993-05-12
2010-11-30
[ "astro-ph" ]
Anatoly Klypin, Jon Holtzman, Joel Primack, and Eniko Regos
astro-ph/9305016
\bf Combustion Gasdynamics in Proto-Neutron Stars
The possible conversion of neutron matter to strange matter and its relevance to astrophysical problems are discussed. Particular attention is paid to the {\it form} in which this hypothetical burning process should be propagated in dense matter and to the {\it moment} when it should start.
1993-05-12
2007-05-23
[ "astro-ph" ]
J.E.Horvath