id large_stringlengths 9 16 | title large_stringlengths 1 382 | abstract large_stringlengths 3 6.09k | publish_date date32 | update_date date32 | categories large listlengths 1 13 | authors large_stringlengths 3 62.8k |
|---|---|---|---|---|---|---|
astro-ph/9505020 | The Velocity Dispersion -- Temperature Correlation from a Limited
Cluster Sample | Most studies of correlations between X-ray and optical properties of galaxy
clusters have used the largest samples of data available, regardless of the
morphological types of clusters included. Given the increasing evidence that
morphology is related to a cluster's degree of dynamical evolution, we approach
the study o... | 1995-05-04 | 2009-10-28 | [
"astro-ph"
] | Christina M. Bird (U. Kansas), Richard F. Mushotzky (GSFC) and
Christopher A. Metzler (U. Michigan) |
astro-ph/9505015 | From Microwave Anisotropies to Cosmology | Fluctuations in the temperature of the cosmic microwave background have now
been detected over a wide range of angular scales, and a consistent picture
seems to be emerging. This article describes some of the implications for
cosmology. Analysis of all the published detections suggests the existence of a
peak on degree... | 1995-05-04 | 2009-10-28 | [
"astro-ph"
] | Douglas Scott, Joe Silk & Martin White |
astro-ph/9505022 | Feasibility of Measuring the Cosmological Constant Lambda and Mass
Density Omega using Type Ia Supernovae | We explore the feasibility of resurrecting the apparent magnitude-redshift
relation for a ``standard candle'' to measure the cosmological constant and
mass density. We show that type Ia supernovae, if measured with 0.15 mag
uncertainty out to a redshift of z=1, may provide a good standard candle or
calibrated candle fo... | 1995-05-04 | 2014-10-13 | [
"astro-ph"
] | Ariel Goobar and Saul Perlmutter |
astro-ph/9505018 | A Collision of Subclusters in Abell 754 | We present direct evidence of a collision of subclusters in the galaxy
cluster Abell 754. Our comparison of new optical data and archival ROSAT PSPC
X-ray data reveal three collision signatures predicted by n-body/hydrodynamical
simulations of hierarchical cluster evolution. First, there is strong evidence
of a non-hyd... | 1995-05-04 | 2009-10-28 | [
"astro-ph"
] | Ann I. Zabludoff (OCIW) and Dennis Zaritsky (UCO/Lick Obs., UCSC) |
astro-ph/9505016 | On the Detectability of Very Massive Compact Objects with Gravitational
Microlensing | If the dark halo of our galaxy is made of compact objects as massive as M =
10^6 solar masses, their detection by means of ordinary microlensing searches
would take a very long time as the characteristic time scale of such a lensing
event, t_0, is approximately 200 years. Fortunately, the very high
magnification events... | 1995-05-04 | 2007-05-23 | [
"astro-ph"
] | Bohdan Paczynski (Princeton University Observatory) |
astro-ph/9505019 | Probing For Machos of Mass $10^{-15}M_\odot$-$10^{-7}M_\odot$ with
Gamma-Ray Burst Parallax Spacecraft | Two spacecraft separated by $\sim 1\,\au$ and equipped with gamma-ray burst
(GRB) detectors could detect or rule out a cosmological density of Massive
Compact Halo Objects (MACHOs) in the mass range $10^{-15} M_{\odot}\lsim M
\lsim 10^{-7} M_{\odot}$ provided that GRBs prove to be cosmological.
Previously devised metho... | 1995-05-04 | 2009-10-28 | [
"astro-ph"
] | Robert J. Nemiroff and Andrew Gould |
astro-ph/9505021 | Satellites in Discs: Regulating the Accretion Luminosity | We demonstrate, using a simple analytic model, that the presence of a massive
satellite can globally modify the structure and emission properties of an
accretion disc to which it is tidally coupled. We show, using two levels of
numerical approximation, that the analytic model gives reasonable results. The
results are a... | 1995-05-04 | 2015-06-24 | [
"astro-ph"
] | Dave Syer (CITA), Cathie Clarke (QMW) |
astro-ph/9505023 | A Supernova at z = 0.458 and Implications for Measuring the Cosmological
Deceleration | We have begun a program to discover high-redshift supernovae ($z \approx$
0.25--0.5), and study them with follow-up photometry and spectroscopy. We
report here our first discovery, a supernova at $z = 0.458$. The photometry for
this supernova closely matches the lightcurve calculated for this redshift from
the template... | 1995-05-04 | 2014-10-13 | [
"astro-ph"
] | S. Perlmutter, C. R. Pennypacker, G. Goldhaber, A. Goobar, R. A.
Muller, H. J. M. Newberg, J. Desai, A. G. Kim, M. Y. Kim, I. A. Small, B. J.
Boyle, C. S. Crawford, R. G. McMahon, P. S. Bunclark, D. Carter, M. J. Irwin,
R. J. Terlevich, R. S. Ellis, K. Glazebrook, W. J. Couch, J. R. Mould, T. A.
Small, and R. G... |
astro-ph/9505009 | Possible association of ultra-high-energy cosmic-ray events with strong
gamma-ray bursts | We point out that each of the error boxes of the two highest-energy
cosmic-ray shower events known, overlaps with that of a strong gamma-ray burst
(GRB). The GRBs precede the cosmic rays by 5.5, and 11 months respectively. In
one case the strongest known cosmic ray is paired with the strongest gamma-ray
burst in the BA... | 1995-05-03 | 2011-05-05 | [
"astro-ph",
"hep-ex",
"hep-ph"
] | Mordehai Milgrom and Vladimir Usov (Weizmann Institute) |
astro-ph/9505012 | LONG WAVELENGTH OBSERVATIONS OF HIGH GALACTIC LATITUDE DUST | The properties of high latitude dust are of great interest to extragalactic
astronomers and cosmologists. It is proposed here that essentially all high
Galactic latitude interstellar dust is at a typical temperature of about 20~K
(i.e. it is warm dust) and that if any cold high latitude interstellar dust
exists, its em... | 1995-05-03 | 2009-10-28 | [
"astro-ph"
] | George F. Smoot (Berkeley) |
astro-ph/9505011 | A PRELIMINARY CLASSIFICATION SCHEME FOR THE CENTRAL REGIONS OF LATE-TYPE
GALAXIES | The large-scale prints in The Carnegie Atlas of Galaxies have been used to
formulate a classification scheme for the central regions of late-type
galaxies. Systems that exhibit small bright central bulges or disks (type CB)
are found to be of earlier Hubble type and of higher luminosity than galaxies
that do not contai... | 1995-05-03 | 2009-10-28 | [
"astro-ph"
] | Sidney van den Bergh |
astro-ph/9505010 | Mass Distributions of Clusters Using Gravitational Magnification | Lensing in the context of rich clusters is normally quantified from small
image distortions, yielding a relative mass distribution in the limit of weak
lensing. Here we show the magnification effect of lensing can also be mapped
over a cluster, resulting in absolute mass determinations for the weak limit.
Furthermore, ... | 1995-05-03 | 2016-08-30 | [
"astro-ph"
] | Tom Broadhurst |
astro-ph/9505014 | Binary galaxies and alternative physics. I. A qualitative application of
MOND and Mannheim-Kazanas gravity | Binary galaxies are modeled as point-masses obeying the non-Newtonian MOND
and Mannheim-Kazanas (MKG) theories of gravity. Random samples of such systems
are generated by means of Monte Carlo simulations of binary orbits. Model pairs
have total masses and mass ratios similar to pairs in the cataloged sample used
in the... | 1995-05-03 | 2011-05-23 | [
"astro-ph"
] | D.S.L. Soares (Physics Department - UFMG/Brazil) |
astro-ph/9505013 | A Gravitational Lens Solution for IRAS F10214+4724 | We show that the high redshift IRAS source F10214 is highly magnified by the
gravitational field of an intervening elliptical galaxy, accounting for its
many anomalous properties. Detailed radio and near-IR images identify the IRAS
source with a symmetric arc, centered on a red object, or lensing galaxy. To
explain the... | 1995-05-03 | 2009-10-28 | [
"astro-ph"
] | Tom Broadhurst, Joseph Lehar |
astro-ph/9505008 | Phase-Transition Theory of Instabilities. III. The Third-Harmonic
Bifurcation on the Jacobi Sequence and the Fission Problem | In Papers I and II, we have used a free-energy minimization approach that
stems from the Landau-Ginzburg theory of phase transitions to describe in
simple and clear physical terms the secular and dynamical instabilities as well
as the bifurcations along equilibrium sequences of rotating, self-gravitating
fluid systems.... | 1995-05-02 | 2009-10-28 | [
"astro-ph"
] | D.M. Christodoulou, D. Kazanas, I. Shlosman and J.E. Tohline |
astro-ph/9505004 | Subcluster merging in clusters of galaxies and the cosmological density
parameter | Recent X-ray observations have established that collisions between
subclusters of galaxies are rather common phenomena. Prompted by such
observations, we have performed N-body simulations of two equal-mass
subclusters of galaxies, which are going to merge. We first have confirmed that
only a part of kinetic energy asso... | 1995-05-02 | 2016-08-30 | [
"astro-ph"
] | F. E. Nakamura(Department of Astronomy, Kyoto University), M. Hattori
(MPE) and S. Mineshige(Department of Astronomy, Kyoto University) |
astro-ph/9505002 | On the usage of Flaring Gas Layers to determine the Shape of Dark Matter
Halos | I present a new method of deriving the shape of the dark matter (DM) halos of
spiral galaxies. The method relies on the comparison of model predictions with
high spectral and spatial resolution HI observations of the gas layer.
The potential arising from the {\em total} mass distribution of the galaxy is
used in the ... | 1995-05-02 | 2009-10-28 | [
"astro-ph"
] | Rob P. Olling (Columbia University, New York) |
astro-ph/9505006 | Determination of Malmquist Bias and Selection Effects from Monte-Carlo
Simulations | Maps of the peculiar velocity field derived from distance relations are
affected by Malmquist type bias and selection effects. Because of the large
number of interdependent effects, they are in most cases difficult to treat
analytically. Monte Carlo simulations are used to understand and evaluate these
effects. In thes... | 1995-05-02 | 2009-10-28 | [
"astro-ph"
] | Wolfram Freudling, Luiz N. Da Costa, Gary Wegner, Riccardo Giovanelli,
Martha P. Haynes and John J. Salzer |
astro-ph/9505007 | High redshift AGNs from the 1Jy catalogue and the magnification bias | We have found a statistically significant (99.1 \%) excess of red ($O-E>2$)
galaxies with photographic magnitudes $E<19.5$, $O< 21$ taken from the APM Sky
Catalogue around $z \sim 1$ radiosources from the 1Jy catalogue. The amplitude,
scale and dependence on galaxy colours of the observed overdensity are
consistent wit... | 1995-05-02 | 2009-10-28 | [
"astro-ph"
] | N. Benitez and E. Martinez-Gonzalez |
astro-ph/9505005 | Approximation Methods for Non-linear Gravitational Clustering | We discuss various analytical approximation methods for following the
evolution of cosmological density perturbations into the strong (i.e.
nonlinear) clustering regime. These methods can be classified into five types:
(i) simple extrapolations from linear theory, such as the high--peak model and
the lognormal model; (... | 1995-05-02 | 2008-11-26 | [
"astro-ph"
] | Varun Sahni and Peter Coles |
astro-ph/9505003 | Mechanical alignment of suprathermally rotating grains | It is shown that mechanical alignment of grains can be efficient for grains
rotating suprathermally, i.e. with kinetic energy substantially exceeding $k$
(the Boltzmann constant) over any temperature in the system. The paper studies
suprathermal rotation caused by H$_{2}$ formation and the alignment that takes
place du... | 1995-05-01 | 2009-10-28 | [
"astro-ph"
] | A. Lazarian |
astro-ph/9505001 | Substructure in Clusters of Galaxies and the value of ${\bf\Omega}$ | We investigate the formation of clusters of galaxies in an expanding universe
using a new code that regrids at a region of high density. In particular we
investigate two models for the initial conditions, both with the standard CDM
power spectrum - one has $\Omega = 1$ and the other $\Omega = 0.2$. Both
universes have ... | 1995-05-01 | 2015-06-24 | [
"astro-ph"
] | Suvendra N. Dutta |
astro-ph/9504101 | Decaying $\Lambda$ cosmologies and statistical properties of
gravitational lenses | In this paper we investigate the statistical properties of gravitational
lenses for models in which a cosmological term decreases with time as $\Lambda
\propto a^{-m}$, where $a$ is the scale factor and $m$ is a parameter ($0 \leq
m < 3$). We show that for given low values of the present matter density
parameter $\Omeg... | 1995-04-28 | 2015-06-24 | [
"astro-ph"
] | L. F. Bloomfield Torres and I. Waga |
astro-ph/9504100 | GRAIN ALIGNMENT IN THE TAURUS DARK CLOUD | Variations in polarization efficiency (p/A) of interstellar grains as a
function of environment place vital constraints on models for the mechanism of
their alignment. We use polarimetry of background field stars to investigate
alignment in the Taurus dark cloud as a function of optical depth for
extinctions of A_K < 2... | 1995-04-28 | 2009-10-28 | [
"astro-ph"
] | P.A. Gerakines(1,2) and D.C.B. Whittet(1) (1- Leiden Observatory,
Leiden, The Netherlands; 2- Dept. of Physics, Rensselaer Polytechnic Inst) |
astro-ph/9504097 | Reconciling Inflation with Openness | It is already understood that the increasing observational evidence for an
open Universe may be reconciled with inflation if our horizon is contained
inside one single huge bubble nucleated during the inflationary phase
transition. In the scenario we present here, the Universe consists of
infinitely many superhorizon b... | 1995-04-27 | 2009-10-28 | [
"astro-ph"
] | Luca Amendola, Carlo Baccigalupi and Franco Occhionero |
astro-ph/9504095 | ASCA observations of the Seyfert 1 galaxies Mrk1040 and MS0225.5+3121 | We present {\it ASCA} observations of the Seyfert 1 galaxies Mrk~1040 and
MS~0225.5+3121. Mrk~1040 was found to have decreased in flux by almost a factor
of 4 since an {\it EXOSAT} observation 10\,years ago. The energy spectrum of
Mrk~1040 displays complexity both at soft energies (below 0.8\thinspace keV)
and at hard ... | 1995-04-27 | 2015-06-24 | [
"astro-ph"
] | C. S. Reynolds, A. C. Fabian and H. Inoue |
astro-ph/9504099 | The Masses of Nearby Dwarfs can be Determined with Gravitational
Microlensing | Microlensing of distant stars in the Milky Way by the nearby high proper
motion stars offers a direct way to precisely measure the masses of single
lower main sequence stars and brown dwarfs. | 1995-04-27 | 2007-05-23 | [
"astro-ph"
] | B. Paczynski |
astro-ph/9504098 | Relativity Experiments in the Solar System | Recent theoretical works on alternative metric theories of gravity give
greater significance to solar-system tests of General Relativity. In
particular, it is suggested that the post-Newtonian parameter $\gamma$ ought to
be determined with great precision in order to discover possible preferred
frame effects or effects... | 1995-04-27 | 2009-09-25 | [
"astro-ph"
] | Giacomo Giampieri (Jet Propulsion Laboratory) |
astro-ph/9504096 | Omega_baryon and the Geometry of Intermediate Redshift Lyman alpha
Absorption Systems | Estimates of Omega_baryon from primordial nucleosynthesis together with
standard assumptions about the ionization state of low column density Lyman
alpha forest clouds can be used to determine an upper limit for the cloud
thickness along the line of sight. This upper limit provides significant
constraints on the axis r... | 1995-04-27 | 2016-06-08 | [
"astro-ph"
] | Michael Rauch (Carnegie Observatories) & Martin G. Haehnelt
(Max-Planck-Institut fuer Astrophysik) |
astro-ph/9504093 | Soft X-ray properties of "narrow-line" Seyfert 1 galaxies | We report on AGN with extremely soft X-ray spectra observed with ROSAT. From
their optical emission lines these objects are classified as narrow-line
Seyfert 1 galaxies (NLS1), almost all with extremely large Fe II/H-beta ratios
and relatively narrow optical lines of hydrogen. Our results are based on a
systematic stud... | 1995-04-26 | 2007-05-23 | [
"astro-ph"
] | Th. Boller, W.N. Brandt, H. Fink |
astro-ph/9504090 | The thick disc of the Galaxy: Sequel of a merging event | Accurate characterization of thick disc properties from recent kinematic and
photometric surveys provides converging evidences that this intermediate
population is a sequel of the violent heating of early disc populations by a
merging satellite galaxy.
The thick disc population is revisited under the light of new dat... | 1995-04-26 | 2011-05-23 | [
"astro-ph"
] | Annie C. Robin, Misha Haywood, Cr\'ez\'e, Devendra K. Ojha and Olivier
Bienaym\'e |
astro-ph/9504091 | Microlensing Search of $10^6$ Quasars | By monitoring $10^6$ quasars one could search for lensing by stars and
Massive Compact Halo Objects (Machos) out to redshifts $z\sim 4$. If Machos
have a present cosmological density $\Omega_{L,0}=1\%$, then the expected event
rate is $\Gamma\sim 200\,\yr^{-1}$. The expected event rate for known stars in
galaxies is $\... | 1995-04-26 | 2009-10-28 | [
"astro-ph"
] | Andrew Gould |
astro-ph/9504094 | A Merger Origin for X-Structures in S0 Galaxies | Using numerical simulation, we study the response of a disk galaxy to a
merger involving a low-mass satellite companion. During a prograde satellite
accretion, the disk galaxy forms a strong bar in response to the perturbation
of the companion. After the accretion event is over, the bar buckles vertically
due to a bend... | 1995-04-26 | 2007-05-23 | [
"astro-ph"
] | Chris Mihos, Ian Walker, Lars Hernquist (UC Santa Cruz), Claudia
Mendes de Oliviera (ESO and Instituto Astonomico e Geofisico), and Mike Bolte
(UC Santa Cruz) |
astro-ph/9504092 | Automated classification of IUE low dispersion spectra (I) | Along the life of the IUE project, a large archive with spectral data has
been generated, requiring automated classification methods to be analyzed in an
objective form. Previous automated classification methods used with IUE spectra
were based on multivariate statistics. In this paper, we compare two
classification me... | 1995-04-26 | 2019-08-15 | [
"astro-ph"
] | E. F. Vieira (LAEFF - INTA - Spain), J. D. Ponz (ESA) |
astro-ph/9504088 | The Discovery of a Short Period Double-Degenerate Binary Star | We have found that the white dwarf PG 1101+364 is a double-lined white
dwarf/white dwarf binary with an orbital period of 3.47 hours. PG 1101+364 is
the shortest period detached double-degenerate yet found and gravitational
radiation will cause it to merge in 2.5 X 10**9 years. PG 1101+364 has a mass
ratio of 0.87 +/- ... | 1995-04-25 | 2016-06-08 | [
"astro-ph"
] | T.R. Marsh (Southampton) |
astro-ph/9504089 | Cosmic density and velocity fields in Lagrangian perturbation theory | A first- and second-order relation between cosmic density and
peculiar-velocity fields is presented. The calculation is purely Lagrangian and
it is derived using the second-order solutions of the Lagrange-Newton system
obtained by Buchert & Ehlers. The procedure is applied to two particular
solutions given generic init... | 1995-04-25 | 2011-05-23 | [
"astro-ph"
] | Mikel Susperregi and Thomas Buchert |
astro-ph/9504080 | Is the galactic halo baryonic? | Recent observations of microlensing events in the Large Magellanic Cloud
suggest that a sizeable fraction of the galactic halo is in form of MACHOs with
mass less than abou 0.1 M_{\odot}. Here we argue that molecular clouds (mainly
H_2) located in the galactic halo can contribute substantially to its total
mass. We out... | 1995-04-24 | 2007-05-23 | [
"astro-ph"
] | F.De Paolis, G.Ingrosso, Ph.Jetzer and M.Roncadelli |
astro-ph/9504081 | LIGHT PHOTINOS AS DARK MATTER | There are good reasons to consider models of low-energy supersymmetry with
very light photinos and gluinos. In a wide class of models the lightest
$R$-odd, color-singlet state containing a gluino, the $\r0$, has a mass in the
1-2 GeV range and the slightly lighter photino, $\pho$, would survive as the
relic $R$-odd spe... | 1995-04-24 | 2016-08-24 | [
"astro-ph",
"hep-ph"
] | Glennys R. Farrar and Edward W. Kolb |
astro-ph/9504085 | Analytic approach to the polarization of the cosmic microwave background
in flat and open universes | We develop an analytic method and approximations to compute the polarization
induced in the cosmic microwave background radiation on a wide range of angular
scales by anisotropic Thomson scattering in presence of adiabatic scalar
{(energy-density)} linear fluctuations. The formalism is an extension to the
polarized cas... | 1995-04-24 | 2009-10-28 | [
"astro-ph",
"gr-qc"
] | Matias Zaldarriaga and Diego D. Harari (Universidad de Buenos Aires) |
astro-ph/9504083 | The Extragalactic Neutrino Background Radiations From Blazars and Cosmic
Rays | Blazar emission of gamma rays and cosmic ray production of gamma rays in
gas-rich clusters have been proposed recently as alternative sources of the
high energy extragalactic diffuse gamma ray background radiation. We show that
these sources also produce a very different high energy extragalactic diffuse
neutrino backg... | 1995-04-24 | 2014-10-13 | [
"astro-ph"
] | Arnon Dar and Nir J. Shaviv (Technion, Haifa, Israel) |
astro-ph/9504087 | EVOLUTION OF THE POTENTIAL IN COSMOLOGICAL GRAVITATIONAL CLUSTERING | The potential is a constant to linear order in cosmological gravitational
clustering. In this Letter we present results of testing the conjecture,
proposed by Pauls and Melott (1995), that the effect of nonlinear evolution on
the potential can be better described by smoothing it on the scale of
nonlinearity. We show tw... | 1995-04-24 | 2009-10-28 | [
"astro-ph",
"gr-qc"
] | Adrian L. Melott, B.S. Sathyaprakash, and Varun Sahni |
astro-ph/9504082 | Dark Matter and Big Bang Nucleosynthesis | The recently observed Deuterium abundance in a low- metallicity high-redshift
hydrogen cloud, which is about ten times larger than that observed in the near
interstellar medium, is that expected from the Standard Big Bang
Nucleosynthesis theory and the observed abundances of $^4$He and $^7$Li
extrapolated to their prim... | 1995-04-24 | 2009-10-28 | [
"astro-ph"
] | Arnon Dar (Technion, Haifa, Israel) |
astro-ph/9504086 | The lens parallax method: determining redshifts of faint blue galaxies
through gravitational lensing | We propose a new technique, which we call the lens parallax method, to
determine simultaneously the redshift distribution of the faint blue galaxies
and the mass distributions of foreground clusters of galaxies. The method is
based on gravitational lensing and makes use of the following: (1) the
amplitude of lensing-in... | 1995-04-24 | 2009-10-28 | [
"astro-ph"
] | Matthias Bartelmann and Ramesh Narayan |
astro-ph/9504084 | The power spectrum in a strongly inhomogeneous Universe | A crucial issue in cosmology is the determination of the fluctuation power
spectrum.The standard picture of the matter clustering, the Cold Dark Matter
model (and its variant), assumes that,on scales smaller than a certain
``flattening scale'' $\lambda_f$, the power spectrum increases with the scale,
while on much larg... | 1995-04-24 | 2009-10-28 | [
"astro-ph"
] | Francesco Sylos Labini and Luca Amendola |
astro-ph/9504079 | THE OPTICAL GRAVITATIONAL LENSING EXPERIMENT. THE CATALOG OF PERIODIC
VARIABLE STARS IN THE GALACTIC BULGE. II. PERIODIC VARIABLES IN FOUR BAADE'S
WINDOW FIELDS: BW1, BW2, BW3 AND BW4 | We present the second part of the OGLE Catalog of Periodic Variable Stars in
the Galactic bulge. 800 variable stars found in four Baade's Window fields BW1,
BW2, BW3 and BW4 are presented. Among them 71 are classified as pulsating, 465
as eclipsing and 264 as miscellaneous type. The Catalog and individual
observations ... | 1995-04-23 | 2007-05-23 | [
"astro-ph"
] | A. UDALSKI, M. SZYMANSKI, J. KALUZNY, M. KUBIAK, M. MATEO and W.
KRZEMINSKI |
astro-ph/9504078 | Statistical Determination of the MACHO Mass Spectrum | The mass function of 51 Massive Compact Objects (MACHOs) detected toward the
Galactic bulge is statistically estimated from Einstein ring crossing times
$t_{\rm e}$. For a Gaussian mass function, the best fitting parameters are
$\langle \log (m/M_{\odot}) \rangle = -1.12$ and $\sigma_{\log (m/M_{\odot})} =
0.57$. If th... | 1995-04-22 | 2009-10-28 | [
"astro-ph"
] | Cheongho Han and Andrew Gould |
astro-ph/9504077 | On the Source and Location of Temporal Variability in Fireballs | Most cosmological models for gamma-ray bursts invoke the production of a
``fireball'' in a compact region, as indicated by the short time variability of
the observed GRBs. The high density of $e^+e^-$ pairs in such fireballs
inevitably makes them opaque to gamma-rays and requires the gamma-ray emission
to take place on... | 1995-04-22 | 2007-05-23 | [
"astro-ph"
] | Nir J. Shaviv |
astro-ph/9504075 | Gamma-Ray Burst Peak Duration as a Function of Energy | Gamma-ray burst time histories often consist of many peaks. These peaks tend
to be narrower at higher energy. If gamma-ray bursts are cosmological, the
energy dependence of gamma-ray burst time scales must be understood in order to
correct the time scale dependence due to the expansion of the universe. By
using the ave... | 1995-04-21 | 2009-10-28 | [
"astro-ph"
] | E. E. Fenimore, J. J. M. in 't Zand, J. P. Norris, J. T. Bonnell, and
R. J. Nemiroff |
astro-ph/9504076 | PKS 2349$-$014: A LUMINOUS QUASAR WITH THIN WISPS, A LARGE OFF-CENTER
NEBULOSITY, AND A CLOSE COMPANION GALAXY | HST images (WFC2) of \pks show that this luminous nearby quasar is
interacting with diffuse (presumably galactic) material. Two thin wisps that
have a total extent of about 20 kpc (for $H_0 = 100$ \kms ${\rm Mpc}^{-1}$ and
$\Omega_0 = 1.0$) are observed to approximately surround the quasar. One of the
wisps appears to ... | 1995-04-21 | 2009-10-28 | [
"astro-ph"
] | J. N. Bahcall, Kirhakos, Sofia, and D. P. Schneider |
astro-ph/9504074 | THE EVOLUTION OF ACCRETION DISKS WITH CORONAE: A MODEL FOR THE
LOW-FREQUENCY QUASI-PERIODIC OSCILLATIONS IN X-RAY BINARIES | The global nonlinear time dependent evolution of accretion disk-corona
systems in X-ray binary sources has been investigated to provide an
understanding of the low frequency ($\sim 0.04$~Hz) quasi-periodic oscillations
(QPOs) observed recently in the Rapid Burster MXB 1730-335 and in some black
hole candidates sources ... | 1995-04-21 | 2009-10-28 | [
"astro-ph"
] | Marek A. Abramowicz, Xingming Chen, and Ronald E. Taam |
astro-ph/9504073 | Limitation of the Press-Schechter Formalism | The Press-Schechter(PS) formalism for the mass function of the collapsed
objects are reanalyzed. The factor of two in the Press-Schechter formalism is
argued to be correct in the sharp $k$-space filter even when we use the another
approach proposed by Jedamzik(1994) in the cloud-in-cloud problem, which is
different fro... | 1995-04-21 | 2016-08-30 | [
"astro-ph"
] | T.Yano, M.Nagashima and N.Gouda |
astro-ph/9504068 | The Cambridge-Cambridge ROSAT Serendipity Survey - II. Classification of
X-ray Luminous Galaxies | We present the results of an intermediate-resolution (1.5\AA) spectroscopic
study of 17 X-ray luminous narrow emission-line galaxies previously identified
in the Cambridge-Cambridge {\it ROSAT} Serendipity Survey and the {\it
Einstein} Extended Medium Sensitivity Survey. Emission-line ratios reveal that
the sample is c... | 1995-04-20 | 2015-06-24 | [
"astro-ph"
] | B.J.Boyle, R.G.McMahon, B.J.Wiles, M.Elvis |
astro-ph/9504065 | The Determination of the `Diffusion Coefficients' and the Stellar Wind
Velocities for X-Ray Binaries | The distribution of neutron stars (NS's) is determined by stationary solution
of the Fokker-Planck equation. In this work using the observed period changes
for four systems: Vela X-1, GX 301-2, Her X-1 and Cen X-3 we determined D, the
'diffusion coefficient',-parameter from the Fokker-Planck equation. Using
strong depe... | 1995-04-20 | 2009-10-28 | [
"astro-ph"
] | V.M.Lipunov and S.B.Popov |
astro-ph/9504063 | Determination of Distance from Time Dilation of Cosmological Gamma-Ray
Bursts | The isotropic distribution of gamma-ray bursts as observed with the Burst and
Transient Experiment (BATSE) strongly suggests that the bursts are at
cosmological distances. At such distances, the expansion of the universe should
redshift the spectra and stretch the temporal structure. We relate the observed
peak intensi... | 1995-04-20 | 2009-10-28 | [
"astro-ph"
] | Ed E. Fenimore and Joshua S. Bloom |
astro-ph/9504066 | Population synthesis of X-ray sources at the Galactic center | X-ray binary population at the Galactic center is proposed here to form as a
result of a starburst, which is synthesized by using the ``Scenario Machine''
code of binary star evolution. For the currently assumed starburst age of 4-7
millions years, our results are consistent with the recent {\it GRANAT} X-ray
observati... | 1995-04-20 | 2008-02-03 | [
"astro-ph"
] | S.B. Popov, V.M. Lipunov, L.M. Ozernoy, K.A. Postnov, and M.E.
Prokhorov |
astro-ph/9504072 | Hot and Cold Spots in the First plus Second Year COBE/DMR Maps | Density perturbations at the decoupling epoch produce angular fluctuations in
the temperature of the Cosmic Microwave Background (CMB) radiation that may
appear as hot and cold spots. Observational data of the CMB includes
instrumental noise in addition to the cosmological signal. One would like to
determine which of t... | 1995-04-20 | 2009-10-28 | [
"astro-ph"
] | Laura Cayon & George Smoot (Lawrence Berkeley Laboratory Center for
Particle Astrophysics) |
astro-ph/9504070 | PAIRWISE VELOCITIES OF GALAXIES IN THE CFA AND SSRS2 REDSHIFT SURVEYS | (compressed version) We combine the CfA Redshift Survey (CfA2) and the
Southern Sky Redshift Survey (SSRS2) to estimate the pairwise velocity
dispersion of galaxies $\sig12$ on a scale of $\sim 1 \hmpc$. Both surveys are
complete to an apparent magnitude limit $B(0)=15.5$. Our sample includes 12,812
galaxies distribute... | 1995-04-20 | 2009-10-28 | [
"astro-ph"
] | R.O. Marzke, M.J. Geller, L.N. da Costa, J.P. Huchra |
astro-ph/9504069 | Faint UBVRI CCD sequences for wide-field surveys - I | We present the first results of a campaign to secure deep UBVRI CCD
photometric calibration in all UK Schmidt equatorial fields with galactic
latitudes |b| > 50deg. In this paper we provide information on deep BVRI
sequences (B<22) in 14 UK Schmidt survey fields centred at declination=0deg.
Deep U sequences have been o... | 1995-04-20 | 2015-06-24 | [
"astro-ph"
] | B.J.Boyle, T.Shanks, S.M.Croom |
astro-ph/9504061 | A Simulation of Ly-alpha Absorption Forests in Linear Approximation in
Cold and Cold+Hot Dark Matter Models | Our goal in this paper is to test some popular dark matter models by Ly-alpha
forest in QSO spectra. Recent observations of the size and velocity of Ly-alpha
forest clouds have indicated that the Ly-alpha absorption is probably not given
by collapsed objects, but pre-collapsed regions in the baryonic density field.
The... | 1995-04-20 | 2009-10-28 | [
"astro-ph"
] | Hongguang BI, Jian GE and Li-Zhi FANG |
astro-ph/9504067 | The environments of z<0.3 QSOs | Based on a cross-correlation analysis of X-ray selected QSOs with faint
(B<20.5) galaxies, we find a 5sigma galaxy excess around low-redshift (z<0.3)
QSOs with an amplitude identical to that of the galaxy angular correlation
function. The similarity between QSO-galaxy clustering and galaxy-galaxy
clustering suggests th... | 1995-04-20 | 2007-05-23 | [
"astro-ph"
] | B.J.Boyle, R.J.Smith, S.J.Maddox |
astro-ph/9504071 | CBR Anisotropy and the Running of the Scalar Spectral Index | Accurate ($\lesssim 1\% $) predictions for the anisotropy of the Cosmic
Background Radiation (CBR) are essential for using future high-resolution
($\lesssim 1^\circ$) CBR maps to test cosmological models. In many inflationary
models the variation (``running'') of the spectral index of the spectrum of
density perturbati... | 1995-04-20 | 2010-01-06 | [
"astro-ph",
"hep-ph"
] | Arthur Kosowsky (Harvard) and Michael S. Turner (U. Chicago/FNAL) |
astro-ph/9504064 | Reverberation mapping of the central regions of active galactic nuclei
using high-energy gamma-ray observations | We calculate the time- and energy-dependent opacity of high-energy gamma-rays
attenuated by pair production interaction with accretion-flare photons that are
scattered by gas and dust surrounding thenuclei of active galaxies. We show
that the temporal behavior of the high-energy opacity cutoff can be used in
conjunctio... | 1995-04-20 | 2007-05-23 | [
"astro-ph"
] | M. B\"ottcher, C. D. Dermer |
astro-ph/9504060 | Beyond the Thin Lens Approximation | We obtain analytic formulae for the null geodesics of
Friedmann-Lema\^{\i}tre-Robertson-Walker spacetimes with scalar perturbations
in the longitudinal gauge. From these we provide a rigorous derivation of the
cosmological lens equation, and obtain an expression for the magnification of a
bundle of light rays without r... | 1995-04-19 | 2009-10-28 | [
"astro-ph",
"gr-qc"
] | Ted Pyne and Mark Birkinshaw |
astro-ph/9504058 | The magnetic field in the Coma cluster | The polarization data of the radio galaxy NGC4869, belonging to the Coma
cluster and located in its central region, allow us to obtain information on
the structure of magnetic field associated with the cluster itself. A magnetic
field of $\sim$ 8.5 $\mu$G, tangled on scales of the order of less than 1 kpc,
is required ... | 1995-04-19 | 2008-02-03 | [
"astro-ph"
] | L.Feretti, D. Dallacasa, G. Giovannini, A. Tagliani |
astro-ph/9504062 | Phase-Transition Theory of Instabilities. II. Fourth-Harmonic
Bifurcations and Lambda-Transitions | We use a free-energy minimization approach to describe the secular and
dynamical instabilities as well as the bifurcations along equilibrium sequences
of rotating, self-gravitating fluid systems. Our approach is fully nonlinear
and stems from the Ginzburg-Landau theory of phase transitions. In this paper,
we examine fo... | 1995-04-19 | 2009-10-28 | [
"astro-ph"
] | D.M. Christodoulou, D. Kazanas, I. Shlosman and J.E. Tohline |
astro-ph/9504059 | HE 3-1475 AND ITS JETS | We present spectra and high-resolution images taken with HST, the NTT, the
VLA, and the MPIA/ESO 2.2m of the emission-line star He 3-1475 which we suggest
is a post-AGB star. The star is at the origin of a 15-arcsec-long structure
containing symmetrically opposing bright knots. The knots have radial
velocities of about... | 1995-04-19 | 2009-10-28 | [
"astro-ph"
] | M. Bobrowsky, A.A. Zijlstra, E.K. Grebel, C.G. Tinney, P. te Lintel
Hekkert, G.C. Van de Steene, L. Likkel and T.R. Bedding |
astro-ph/9504054 | Determination of Inflationary Observables by Cosmic Microwave Background
Anisotropy Experiments | Inflation produces nearly Harrison-Zel'dovich scalar and tensor perturbation
spectra which lead to anisotropy in the cosmic microwave background (CMB). The
amplitudes and shapes of these spectra can be parametrized by $Q_S^2$, $r\equiv
Q_T^2/Q_S^2$, $n_S$ and $n_T$ where $Q_S^2$ and $Q_T^2$ are the scalar and
tensor co... | 1995-04-18 | 2009-10-28 | [
"astro-ph"
] | Lloyd Knox |
astro-ph/9504056 | FAR-INFRARED SPECTRAL OBSERVATIONS OF THE GALAXY BY COBE | We derive Galactic continuum spectra from 5-96/cm from COBE/FIRAS
observations. The spectra are dominated by warm dust emission, which may be fit
with a single temperature in the range 16-21 K (for nu^2 emissivity) along each
line of sight. Dust heated by the attenuated radiation field in molecular
clouds gives rise to... | 1995-04-18 | 2012-08-27 | [
"astro-ph"
] | W.T. Reach, E. Dwek, D.J. Fixsen, T. Hewagama, J.C. Mather, R.A.
Shafer, A.J. Banday, C.L. Bennett, E.S. Cheng, R.E. Eplee, Jr., D. Leisawitz,
P.M. Lubin, S.M. Read, L.P. Rosen, F.G.D. Shuman, G.F. Smoot, T.J. Sodroski,
and E.L. Wright |
astro-ph/9504057 | The Physics of Microwave Background Anisotropies | Cosmic microwave background anisotropies provide a vast amount of information
on both structure formation in the universe and the background dynamics and
geometry. The full physical content and detailed structure of anisotropies can
be understood in a simple and intuitive fashion through a systematic
investigation of t... | 1995-04-18 | 2018-01-29 | [
"astro-ph"
] | Wayne Hu, Naoshi Sugiyama and Joseph Silk |
astro-ph/9504053 | Photometric monitoring (1987 to 1994) of the gravitational lens
candidate UM 425 | We present the results of a 7 year long photometric monitoring of two
components (A and B) of UM 425, thought to be images, separated by 6.5", of the
same z = 1.47 quasar. These components have been imaged through an R filter in
order to obtain their light curves. The photometry was obtained by
simultaneously fitting a... | 1995-04-18 | 2019-08-15 | [
"astro-ph"
] | F. Courbin (ESO), P. Magain, M. Remy (Astrophysics intitute, Liege,
Belgium), A. Smette (Kapteyn Astronomical Institute, Netherlands), J.F.
Claesken s (ESO), O. Hainaut (Institute for Astronomy, USA), D. Hutsemekers
(Astrophys ics intitute, Liege, Belgium), G. Meylan (ESO), E. Van Drom (Osaka
University, Japan) |
astro-ph/9504055 | PHOTON SPLITTING IN STRONGLY MAGNETIZED COSMIC OBJECTS -- REVISITED | We reassess the importance of photon splitting to spectral formation in
cosmic X-ray and $\gamma$-ray sources with magnetic fields of several $10^{12}$
gauss. Our analysis is based on the recent numerically accurate evaluation of
the full relativistic expression for photon splitting at neutron star magnetic
field stren... | 1995-04-18 | 2009-10-28 | [
"astro-ph"
] | G\"unter Wunner, Robert Sang and Dagmar Berg (Ruhr-Universit\"at
Bochum) |
astro-ph/9504052 | The velocity peaks in the cold dark matter spectrum on Earth | The cold dark matter spectrum on earth is expected to have peaks in velocity
space. We obtain estimates for the sizes and locations of these peaks. To this
end we have generalized the secondary infall model of galactic halo formation
to include angular momentum of the dark matter particles. This new model is
still sphe... | 1995-04-17 | 2010-11-30 | [
"astro-ph",
"hep-ph"
] | P. Sikivie, I. I. Tkachev and Yun Wang |
astro-ph/9504051 | Ekman Pumping in Compact Astrophysical Bodies | We examine the dynamics of a rotating viscous fluid following an abrupt
change in the angular velocity of the solid bounding surface. We include the
effects of a density stratification and compressibility which are important in
astrophysical objects such as neutron stars. We confirm and extend the
conclusions of previo... | 1995-04-16 | 2014-10-13 | [
"astro-ph"
] | Mark Abney (U. of Chicago), Richard I Epstein (LANL) |
astro-ph/9504049 | X-ray Constraints on the Intrinsic Shapes and Baryon Fractions of Five
Abell Clusters | We analyzed ROSAT PSPC images of the bright, nearby $(z<0.1)$ galaxy clusters
A401, A1656 (Coma), A2029, A2199, and A2256 to constrain their intrinsic shapes
and baryon fractions. Following Buote & Tsai we probed the aggregate structure
of the clusters on scales $\sim 1.5h^{-1}_{80}$ Mpc to reduce effects of
possible s... | 1995-04-15 | 2009-10-28 | [
"astro-ph"
] | David A. Buote and Claude R. Canizares |
astro-ph/9504050 | GRAPESPH: Cosmological SPH simulations with the special purpose hardware
GRAPE | A combined N--body/SPH code is presented which benefits from the high speed
of the special purpose hardware GRAPE (GRAvity PipE). Besides gravitational
forces, GRAPE also returns the list of neighbours and can, therefore, be used
to speed up the hydrodynamical part, too. After the interaction list has been
passed, dens... | 1995-04-15 | 2015-06-24 | [
"astro-ph"
] | Matthias Steinmetz |
astro-ph/9504048 | COSMIC LITHIUM: GOING UP OR COMING DOWN ? | Observations of interstellar lithium provide a valuable complement to studies
of lithium in Pop I and Pop II stars. Large corrections for unseen LiII and for
non-gas phase lithium have provided obstacles to using interstellar data for
abundance determinations. An approach to surmounting these difficulties is
proposed a... | 1995-04-14 | 2009-10-28 | [
"astro-ph"
] | GARY STEIGMAN |
astro-ph/9504047 | THE OPTIMAL N-BODY METHOD FOR STABILITY STUDIES OF GALAXIES | The stability of a galaxy model is most easily assessed through N-body
simulation. Particle-mesh codes have been widely used for this purpose, since
they enable the largest numbers of particles to be employed. We show that the
functional expansion technique, originally proposed by Clutton-Brock for other
simulation pro... | 1995-04-14 | 2009-10-28 | [
"astro-ph"
] | David J.D. Earn and J.A. Sellwood |
astro-ph/9504044 | Globular Clusters in Mergers | From spectrophotometric and chemical evolutionary modelling of interacting
and merging galaxies we predict abundances of burst stars and of globular
clusters (GCs) that may be formed in strong bursts. Observations of young GCs
in merger remnants confirm the predicted metallicities. We investigate their
formation as a r... | 1995-04-13 | 2007-05-23 | [
"astro-ph"
] | Uta Fritze - v. Alvensleben, Andi Burkert |
astro-ph/9504045 | Evolution of the double neutron star merging rate and the cosmological
origin of gamma-ray burst sources | Evolution of the coalescence rate of double neutron stars (NS) and neutron
star -- black hole (BH) binaries are computed for model galaxies with different
star formation rates. Assuming gamma-ray bursts (GRB) to originate from NS+NS
or NS+BH merging in distant galaxies, theoretical logN--logS distributions and
<V/V_max... | 1995-04-13 | 2009-10-28 | [
"astro-ph"
] | V.M. Lipunov, K.A. Postnov, M.E. Prokhorov, and I.E. Panchenko
(Sternberg Astronomical Inst., Moscoww, Russia) |
astro-ph/9504046 | Quantifying the Morphologies and Dynamical Evolution of Galaxy Clusters.
II. Application to a Sample of ROSAT Clusters | We quantify the morphologies and dynamical states of 59 galaxy clusters using
the power-ratio technique of Buote & Tsai applied to ROSAT PSPC X-ray images.
The clusters exhibit a particularly strong $P_2/P_0 - P_4/P_0$ correlation in
the $1h^{-1}_{80}$ Mpc aperture which may be interpreted as an evolutionary
track; the... | 1995-04-13 | 2009-10-28 | [
"astro-ph"
] | David A. Buote and John C. Tsai |
astro-ph/9504043 | Interchange instability in an accretion disc with a poloidal magnetic
field | We investigate the stability to nonaxisymmetric perturbations of an accretion
disc in which a poloidal magnetic field provides part of the radial support
against gravity. Interchange instability due to radial gradients in the
magnetic field are strongly stabilized by the shear flow in the disc. For
smooth field distrib... | 1995-04-12 | 2015-06-24 | [
"astro-ph"
] | H.C. Spruit, R. Stehle and J.C.B. Papaloizou |
astro-ph/9504040 | Parallel Linear General Relativity and CMB Anisotropies | We have developed a code which links scalar-mode fluctuations in the early
universe with those observable at the present time by integrating the coupled,
linearized, Einstein, Boltzmann, and fluid equations in a perturbed flat
Robertson-Walker spacetime. The results are useful both for calculations of the
cosmic microw... | 1995-04-12 | 2009-09-25 | [
"astro-ph"
] | Paul Bode and Edmund Bertschinger |
astro-ph/9504039 | Bright Stars and Recent Star Formation in the Irregular Magellanic
Galaxy NGC2366 | The stellar content of the Im galaxy NGC 2366 is discussed on the basis of
CCD BVR photometry. The three brightest blue and red stars have been used to
estimate its distance, obtaining a balue of 2.9 Mpc. The spatial distribution
of the young stellar population is discussed in the light of the integrated
color indices ... | 1995-04-12 | 2009-10-28 | [
"astro-ph"
] | A.Aparicio, J.Cepa, C.Gallart, H.Castaneda, C.Chiosi, G.Bertelli,
C.Munoz-Tunon, Eduardo Telles, G.Tenorio-Tagle, A.I.Diaz, M.L.Garcia-Vargas,
F. Garzon, R.Ma. Gonzalez-Delgado, M.Mas-Hesse, E.Perez,
J.M.Rodriguez-Espinosa, E.Terlevich, R.J.Terlevich, A.M.Varela, J.M.Vilchez |
astro-ph/9504038 | Dynamics of Abell 2218 from optical and near-IR imagery of arc(let)s and
ROSAT/HRI X-ray map | A mass model of the rich cluster A2218 is presented based on optical and new
near-infrared images of arc(let)s and the ROSAT/HRI X-ray map. A lensing model
is proposed with two dark matter clumps, centered on the two bright galaxies
around which the various arcs are observed. Two of them, close to the most
massive clum... | 1995-04-12 | 2008-02-03 | [
"astro-ph"
] | J.-P. Kneib, Y. Mellier, R. Pello, J. Miralda-Escude, J.-F. Le Borgne,
H. Bohringer, J.-P. Picat |
astro-ph/9504041 | The Structure of Dark Matter Haloes in Dwarf Galaxies | Recent observations indicate that dark matter haloes have flat central
density profiles. Cosmological simulations with non-baryonic dark matter
predict however self similar haloes with central density cusps. This
contradiction has lead to the conclusion that dark matter must be baryonic.
Here it is shown that the dark ... | 1995-04-12 | 2009-10-28 | [
"astro-ph"
] | A. Burkert |
astro-ph/9504042 | Analytical modeling of large-angle CMBR anisotropies from textures | We propose an analytic method for predicting the large angle CMBR temperature
fluctuations induced by model textures. The model makes use of only a small
number of phenomenological parameters which ought to be measured from simple
simulations. We derive semi-analytically the $C^l$-spectrum for $2\leq l\leq
30$ together... | 1995-04-12 | 2009-10-28 | [
"astro-ph"
] | J.C.R.Magueijo (Mullard Radio Astronomy Observatory, Cavendish
Laboratory and DAMTP, Cambridge, UK) |
astro-ph/9504031 | Abundance Histories for QSO Absorption Line Systems | Abundance histories for QSO absorption line systems as a function of redshift
are presented for all metals lighter than gallium. Coupling various
conventional cosmological models with a simple, first--order model for the
chemical evolution of the QSO absorption line systems allows transformation of
the observed abundan... | 1995-04-11 | 2009-10-28 | [
"astro-ph"
] | F.X.Timmes, J.T.Lauroesch and J.W.Truran |
astro-ph/9504035 | NEW TEST FOR THE HUBBLE LAW | The new, simple method is proposed for testing the Hubble law using redshifts
and magnitude from magnitude-limited sample of galaxies. The power law relation
between redshift and distance have been assumed (cz=r^p). The obtained results:
p=1.21 \pm 0.04 (for CfA) and p=0.95 \pm 0.04 (for ESO/LV) confirm linear,
Hubble ... | 1995-04-11 | 2007-05-23 | [
"astro-ph"
] | Jacek Choloniewski |
astro-ph/9504032 | Probing the Era of Galaxy Formation via TeV Gamma Ray Absorption by the
Near Infrared Extragalactic Background | We present models of the extragalactic background light (EBL) based on
several scenarios of galaxy formation and evolution. We have treated galaxy
formation with the Press-Schecter approximation for both cold dark matter (CDM)
and cold+hot dark matter (CHDM) models, representing a moderate ($z_f \sim 3$)
and a late ($z... | 1995-04-11 | 2009-12-10 | [
"astro-ph"
] | D. MacMinn and J.R. Primack |
astro-ph/9504034 | New pulsational properties of eight "anomalous" RR Lyrae variables | CCD photometry in the V band is presented for 7 field RR Lyrae stars selected
from a sample of eight variables which, according to data collected in the
literature, are expected to be {\it ab}-type pulsators, to have short periods
and hence high metallicity, and to be located at high {\it z} from the galactic
plane. Ne... | 1995-04-11 | 2015-06-24 | [
"astro-ph"
] | G. Clementini, M. Tosi, A. Bragaglia, R. Merighi, and C. Maceroni |
astro-ph/9504033 | On improved Cepheid distance estimators | In this paper, we derive a physical argument for the existence of
Period-luminosity and period-luminosity-colour relations at maximum light. We
examine in detail a sample of Cepheids in the Large Magellanic Cloud, and
compare the variance of some PL and PLC type distance indicators based on mean
and maximum light. We s... | 1995-04-11 | 2007-05-23 | [
"astro-ph"
] | Shashi M. Kanbur, Martin A. Hendry |
astro-ph/9504036 | THE ORIGIN OF PLUTO'S ORBIT: IMPLICATIONS FOR THE SOLAR SYSTEM BEYOND
NEPTUNE | The origin of the highly eccentric, inclined, and resonance-locked orbit of
Pluto has long been a puzzle. A possible explanation has been proposed recently
[Malhotra, R., {\it Nature} 365:819-21 (1993)] which suggests that these
extraordinary orbital properties may be a natural consequence of the formation
and early dy... | 1995-04-11 | 2009-10-28 | [
"astro-ph"
] | Renu Malhotra (Lunar and Planetary Institute) |
astro-ph/9504037 | A Wavelet Space-Scale-Decomposition Analysis of Structure and Evolution
fo QSO's Ly$\alpha$ Absorption Lines | A wavelet space-scale decomposition (SSD) analysis of large scale structures
in the universe has been developed. The SSD method of identifying and measuring
structures in the spatial distribution of objects has been demonstrated. The
position and strength (richness) of the identified clusters can be described by
the co... | 1995-04-11 | 2009-10-28 | [
"astro-ph"
] | Jesus Pando and Li-Zhi Fang (University of Arizona Physics Department) |
astro-ph/9504027 | Beat Frequency Modulation of T Tauri Accretion Rates | A general model of magnetically controlled accretion onto T Tauri stars is
presented. In this model the magnetic field is oriented arbitrarily in relation
to the star's rotation axis. The resultant interplay between the magnetic field
and accretion disc causes a variable accretion rate. The dominant timescale of
this v... | 1995-04-10 | 2015-06-24 | [
"astro-ph"
] | K.W. Smith, I.A. Bonnell, G.F. Lewis |
astro-ph/9504030 | Discovery of Diffuse X-ray Emission in 47 Tuc | We present the results of a search for diffuse x-ray sources in a 65 ksec
ROSAT PSPC exposure of 47 Tuc. There is faint, soft emission on the NE side of
the cluster at a distance of 6 arcmin from the core. The location of this
emission along the direction of proper motion of the cluster suggests that it
might be due to... | 1995-04-10 | 2009-10-28 | [
"astro-ph"
] | Martin Krockenberger and J. Grindlay |
astro-ph/9504028 | Observational constraints on blue primordial spectra | Recently, there has been growing interest on primordial ``blue" ($n>1$)
perturbation spectra, motivated both by a composite set of observational data
on large scales and from the point of view of theoretical model building. After
reviewing the theoretical (inflationary) motivations for these blue spectra, we
consider v... | 1995-04-10 | 2009-10-28 | [
"astro-ph"
] | F. Lucchin, S. Colafrancesco, G. de Gasperis, S. Matarrese, S. Mei, S.
Mollerach, L. Moscardini, N. Vittorio |
astro-ph/9504029 | Non-Gaussian Likelihood Function | We generalize the maximum likelihood method to non-Gaussian distribution
functions by means of the multivariate Edgeworth expansion. We stress the
potential interest of this technique in all those cosmological problems in
which the determination of a non-Gaussian signature is relevant, e.g. in the
analysis of large sca... | 1995-04-09 | 2007-05-23 | [
"astro-ph"
] | Luca Amendola (Osservatorio Astronomico di Roma) |
astro-ph/9504024 | Molecular Gas in the Inner 3.2 Kiloparsecs of NGC 2403: Star Formation
at Subcritical Gas Surface Densities | We present a fully sampled map of the inner 3.2 kpc of the nearby spiral
galaxy NGC 2403 in the CO J=1-0 line. These data emphasize the relatively small
contribution of molecular hydrogen to the cold gas content of this galaxy, and
confirm that the gas surface densities in the inner 2.8 kpc of NGC 2403 lie
below the cr... | 1995-04-07 | 2009-10-28 | [
"astro-ph"
] | Michele D. Thornley (U. Maryland) & Christine D. Wilson (McMaster) |
astro-ph/9504022 | LINEAR POTENTIALS IN GALAXIES AND CLUSTERS OF GALAXIES | In a previous paper we presented a typical set of galactic rotation curves
associated with the linear gravitational potential of 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 Newton-Einstein
theory.... | 1995-04-07 | 2009-09-25 | [
"astro-ph"
] | PHILIP D. MANNHEIM (University of Connecticut) |
astro-ph/9504021 | The absorption spectra of Q1107+487 and Q1442+295 | We present the first moderate resolution (approx. 40--120 km/s) spectroscopic
observations of the bright (V<16.7) high-redshift QSOs Q1107+487 (z_{em} =
2.965) and Q1442+295 (z_{em} = 2.669) (Sanduleak & Pesch 1989). The relatively
high signal to noise reached in the spectra along with an extensive wavelength
coverage ... | 1995-04-07 | 2009-10-28 | [
"astro-ph"
] | R. Carballo, X. Barcons, J.K. Webb |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.