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astro-ph/9506070
COSMICS: Cosmological Initial Conditions and Microwave Anisotropy Codes
COSMICS is a package of fortran programs useful for computing transfer functions and microwave background anisotropy for cosmological models, and for generating gaussian random initial conditions for nonlinear structure formation simulations of such models. Four programs are provided: {\bf linger\_con} and {\bf linger\...
1995-06-12
2016-08-30
[ "astro-ph" ]
Edmund Bertschinger
astro-ph/9506076
Acceleration Rates and Injection Efficiencies in Oblique Shocks
The rate at which particles are accelerated by the first-order Fermi mechanism in shocks depends on the angle, \teq{\Tbone}, that the upstream magnetic field makes with the shock normal. The greater the obliquity the greater the rate, and in quasi-perpendicular shocks rates can be hundreds of times higher than those se...
1995-06-12
2009-10-28
[ "astro-ph" ]
D. C. Ellison, M. G. Baring and F. C. Jones
astro-ph/9506074
Can the Tully-Fisher Relation be the Result of Initial Conditions?
We use Monte Carlo realizations of halo formation histories and a spherical accretion model to calculate the expected scatter in the velocity dispersions of galactic halos of a given mass due to differences in their formation times. Assuming that the rotational velocity of a spiral galaxy is determined by the velocity ...
1995-06-12
2009-10-28
[ "astro-ph" ]
Daniel J. Eisenstein and Abraham Loeb (Harvard Univ.)
astro-ph/9506072
Cosmological Perturbation Theory in the Synchronous and Conformal Newtonian Gauges
This paper presents a systematic treatment of the linear theory of scalar gravitational perturbations in the synchronous gauge and the conformal Newtonian (or longitudinal) gauge. It differs from others in the literature in that we give, in both gauges, a complete discussion of all particle species that are relevant to...
1995-06-11
2015-06-24
[ "astro-ph", "hep-ph" ]
Chung-Pei Ma and Edmund Bertschinger
astro-ph/9506071
Sagittarius: The Nearest Dwarf Galaxy
We have discovered a new Galactic satellite galaxy in the constellation of Sagittarius. The Sagittarius dwarf galaxy is the nearest galaxy known, subtends an angle of $> 10$ degrees on the sky, lies at a distance of $24 \kpc$ from the Sun, $\sim 16 \kpc$ from the centre of the Milky Way. Itis comparable in size and lum...
1995-06-10
2015-06-24
[ "astro-ph" ]
Rodrigo Ibata(UBC, Vancouver,CA), G. Gilmore (IoA Cambridge, GB), M.J. Irwin (RGO, Cambridge)
astro-ph/9506066
The outburst of the T Tauri star EX Lupi in 1994
We have observed an outburst of the T Tauri star EX Lup in March 1994. We present both photometric (BVR) and spectroscopic (low and medium resolution) observations carried out during the decline after outburst. The star appears much bluer during outburst due to an increased emission of a hot continuum. This is accompan...
1995-06-09
2007-05-23
[ "astro-ph" ]
Thomas Lehmann, Bo Reipurth, and Wolfgang Brandner
astro-ph/9506063
Unified Schemes for Radio-Loud Active Galactic Nuclei
The appearance of active galactic nuclei (AGN) depends so strongly on orientation that our current classification schemes are dominated by random pointing directions instead of more interesting physical properties. Light from the centers of many AGN is obscured by optically thick circumnuclear matter and in radio-loud ...
1995-06-09
2011-07-18
[ "astro-ph" ]
C. Megan Urry and Paolo Padovani
astro-ph/9506068
Geocentrism reexamined
The universe is nearly isotropic on very large scales. It is much more difficult to show that the universe is radially homogeneous (independent of distance), or equivalently, that it is isotropic about distant points. This taken as an axiom, since if it were not true, then we would occupy a preferred position. This pap...
1995-06-09
2009-10-28
[ "astro-ph" ]
Jeremy Goodman (Princeton University Observatory)
astro-ph/9506067
Peak mass and dynamical friction
We show how the results given by several authors relatively to the mass of a density peak are changed when small scale substructure induced by dynamical friction are taken into account. The peak mass obtained is compared to the result of Peacock \& Heavens (1990) and to the peak mass when dynamical friction is absent t...
1995-06-09
2007-05-23
[ "astro-ph" ]
A. Del Popolo and M. Gambera (Institute of Astronomy, University of Catania, ITALY)
astro-ph/9506069
Globular Cluster Systems As Distance Indicators: Metallicity Effects On The Luminosity Function
We investigate the universality of the globular cluster luminosity function (GCLF) and the use of this function as an extragalactic distance indicator. Previous studies have found an offset between GCLF distances and those obtained with other techniques. We show that this offset can be understood in terms of a metallic...
1995-06-09
2009-10-28
[ "astro-ph" ]
Keith M. Ashman (Kansas), Alberto Conti (Kansas), Stephen E. Zepf (UC Berkeley)
astro-ph/9506065
EUV Emission from Normal Galaxies
Using data from the ROSAT Wide Field Camera all-sky survey, we have established upper limits to the extreme ultraviolet (EUV) flux from a sample of 30 bright, nearby, non-active spiral galaxies. These galaxies were chosen to be those most likely to be detected in the EUV on the basis of (i) low interstellar absorption ...
1995-06-08
2007-05-23
[ "astro-ph" ]
A.M. Read and T.J. Ponman (University of Birmingham, U.K)
astro-ph/9506062
Hot tori around black holes as sources of gamma ray bursts
We investigate the configurations consisting of massive, dense and hot tori around stellar mass Kerr black holes as possible sources of energy for the gamma ray bursts in cosmological hypothesis of their origin. We limit parameters of our models to the values resulting from neutron stars merger calculations or suggeste...
1995-06-08
2008-02-03
[ "astro-ph" ]
M. Jaroszynski (Warsaw University Observatory)
astro-ph/9506057
An Origin for Pulsar Kicks in Supernova Hydrodynamics
It is now believed that pulsars comprise the fastest population of stars in the galaxy. With inferred mean, root-mean-square, and maximum 3-D pulsar speeds of $\sim$300-500 km/s, $\sim$500 km/s, and $\sim$2000 km/s, respectively, the question of the origin of such singular proper motions becomes acute. What mechanism c...
1995-06-08
2009-10-28
[ "astro-ph" ]
Adam Burrows and John Hayes (University of Arizona)
astro-ph/9506059
Probing Dark Matter
Recent novel observations have probed the baryonic fraction of the galactic dark matter that has eluded astronomers for decades. Late in 1993, the MACHO and EROS collaborations announced in this journal the detection of transient and achromatic brightenings of a handful of stars in the Large Magellanic Cloud that are b...
1995-06-08
2009-10-28
[ "astro-ph" ]
Adam Burrows and Jim Liebert (University of Arizona)
astro-ph/9506061
On the Nature of Core Collapse Supernova Explosions
We investigate in this paper the core-collapse supernova explosion mechanism in both one and two dimensions. We verify the usefulness of neutrino-driven overturn (``convection'') between the shock and the neutrinosphere in igniting the supernova explosion. The 2-D simulation of the core of a 15$\mdot$ star that we pres...
1995-06-08
2009-10-28
[ "astro-ph" ]
Adam Burrows and John Hayes (University of Arizona) and Bruce Fryxell (Goddard SFC)
astro-ph/9506060
The Physics of Core-Collapse Supernova Explosions
Fresh insights and powerful numerical tools are revitalizing the theoretical exploration of the supernova mechanism. The realization that the protoneutron star is Rayleigh-Taylor unstable at various times and radii and, hence, that a multi-dimensional perspective is required is one agent of this revolution. However, a ...
1995-06-08
2007-05-23
[ "astro-ph" ]
Adam Burrows anbd John Hayes (University of Arizona)
astro-ph/9506055
Prospects for Detection of Extra-Solar Giant Planets by Next-Generation Telescopes
Interest among astronomers in the detection of extra-solar planets is accelerating with the growing realization that it may soon be technically feasible. The ongoing renaissance in telescope construction and the anticipated launches of new space platforms are encouraging many scientists to review and improve the means ...
1995-06-08
2009-10-28
[ "astro-ph" ]
A. Burrows, D. Saumon, T. Guillot, W.B. Hubbard, and J.I. Lunine
astro-ph/9506058
A Gamma-Ray Monte Carlo Study of the Clumpy Debris of SN1987A
We have performed Monte Carlo calculations of gamma-ray transport in models of the clumpy debris cloud of the LMC supernova, SN1987A, to study the influence of composition mixing and heterogeneity on its emergent gamma-ray and X-ray fluxes. In particular, we have focused on the problematic Ginga band (16 -- 28 keV) flu...
1995-06-08
2009-10-28
[ "astro-ph" ]
Adam Burrows (University of Arizona) and Ken Van Riper (LANL)
astro-ph/9506056
Bar-driven Fueling to a Galactic Central Reagin in a Massive Gas Disk
We have found an effective fueling process to a central region of galaxies with weak bar-like distortion by two dimensional hydrodynamical simulations. Gravitational instability of an elongated gas ring at the inner Lindblad resonance (ILR), which has been reported as an effective fueling mechanism, are not needed for ...
1995-06-08
2015-06-24
[ "astro-ph" ]
Keiichi Wada and Asao Habe
astro-ph/9506064
COBE Observations of the Microwave Counterparts of Gamma Ray Bursts
We have used the data from the COBE satellite to search for delayed microwave emission (31 - 90 GHz) from Gamma Ray Bursts (GRBs). The large $7^\circ$ beam of COBE is well matched to the large positional uncertainties in the GRB locations, although it also means that fluxes from (point source) GRB objects will be dilut...
1995-06-08
2009-10-28
[ "astro-ph" ]
R. K. Schaefer, S.Ali, M. Limon, and L. Piccirillo (Bartol Res. Inst.)
astro-ph/9506046
Search for new pulsating O VI central stars of planetary nebulae
A photoelectric monitoring program has been applied, during the last four years, to five central stars of planetary nebulae (PNNs) with strong O\,VI $\lambda$ 3811--34 \AA \hspace{0.1mm} emission. NGC\,6905 and, marginally, NGC\,2452, show intrinsic luminosity variations, while NGC\,7026, IC\,2003 and NGC\,1501 have co...
1995-06-07
2007-05-23
[ "astro-ph" ]
R. Silvotti, C. Bartolini and L. Stanghellini
astro-ph/9506050
Background X-ray Emission from Hot Gas in CDM and CDM+Lambda Universes: Spectral Signatures
We present a new treatment of two popular models for the growth of structure, examining the X-ray emission from hot gas with allowance for spectral line emission from various atomic species, primarily ``metals". The X-ray emission from the bright cluster sources is not significantly changed from prior work and, as note...
1995-06-07
2016-08-30
[ "astro-ph" ]
Renyue Cen, Hyesung Kang, Jeremiah P. Ostriker and Dongsu Ryu
astro-ph/9506044
Good Abundances from Bad Spectra :II. Application and a New Stellar Color--Temperature Relation
Stellar spectra derived from current multiple-object fiber-fed spectroscopic radial-velocity surveys, of the type feasible with, among other examples, AUTOFIB, 2dF, HYDRA, NESSIE, and the Sloan survey, differ significantly from those traditionally used for determination of stellar abundances. The spectra tend to be of ...
1995-06-07
2007-05-23
[ "astro-ph" ]
J. Bryn Jones, Rosemary F.G. Wyse and Gerard Gilmore
astro-ph/9506053
Counting Pairs of Faint Galaxies
The number of close pairs of galaxies observed to faint magnitude limits, when compared to nearby samples, determines the interaction or merger rate as a function of redshift. The prevalence of mergers at intermediate redshifts is fundamental to understanding how galaxies evolve and the relative population of galaxy ty...
1995-06-07
2009-10-28
[ "astro-ph" ]
David Woods, Gregory G. Fahlman and Harvey B. Richer
astro-ph/9506054
Macho Proper Motions From Optical/Infrared Photometry
Optical/infrared photometry can double the number of proper motion measurements of Massive Compact Objects (MACHOs) relative to single band photometry. The proper motion of a MACHO can be measured by finding the ratio $q$ of the (known) radius of the source star to the Einstein radius of the MACHO, $q=\theta_s/\theta_e...
1995-06-07
2009-10-28
[ "astro-ph" ]
Andrew Gould and Douglas L. Welch
astro-ph/9506051
Pattern in Nonlinear Gravatational Clustering: A Numerical Investigation
The nonlinear clustering of dark matter particles in an expanding universe is usually studied by N-body simulations. One can gain some insight into this complex problem if simple relations between physical quantities in the linear and nonlinear regimes can be extracted from the results of N-body simulations. Hamilton e...
1995-06-07
2008-11-26
[ "astro-ph" ]
T.Padmanabhan, Renyue Cen, Jeremiah P. Ostriker and F J Summers
astro-ph/9506045
Forbidden Fe+ Emission from Supernovae Remnants in M33
Supernovae remnants are known to be luminous sources of infrared [FeII] emission. By studying how the luminosity scales with age, environment and other relevant factors, we can construct an [FeII] luminosity function for supernovae remnants. This will enable us to predict supernovae rates in starburst galaxies that are...
1995-06-07
2015-06-24
[ "astro-ph" ]
S.L. Lumsden (AAO), P.J. Puxley (ROE)
astro-ph/9506048
Rees-Sciama Effect in a CDM Universe
The Rees-Sciama (RS) effect produces fluctuations in the cosmic microwave background (CMB) through the time-dependent gravitational potential in the nonlinear stages of evolution. I investigate the RS effect on the CMB angular power spectrum $C_l$ for several CDM models by combining the results of N-body simulations wi...
1995-06-07
2009-10-28
[ "astro-ph" ]
Uros Seljak (MIT)
astro-ph/9506049
Inflationary Models with Logarithmic Potentials
We examine inflationary universe models driven by scalar fields with logarithmic potentials of the form $V(\phi) = V_0 \phi^p(\ln \phi)^q$. Combining the slow-roll approximation with asymptotic techniques, we identify regions of the potential where inflation may occur and obtain analytic expressions for the evolution o...
1995-06-07
2009-10-28
[ "astro-ph", "gr-qc", "hep-ph" ]
John D. Barrow and Paul Parsons
astro-ph/9506047
The X-ray properties of the merging galaxy pair NGC 4038/9 - the Antennae
We report the results of an X-ray spectral imaging observation of the Antennae with the ROSAT PSPC. 55% of the soft X-ray flux from the system is resolved into discrete sources, including components identified with the galactic nuclei and large HII regions, whilst the remainder appears to be predominantly genuinely dif...
1995-06-07
2015-06-24
[ "astro-ph" ]
A.M. Read, T.J. Ponman (University of Birmingham, U.K), R.D. Wolstencroft (ROE, Edinburgh, U.K.)
astro-ph/9506052
Topology of Large-Scale Structure by Galaxy Type: Hydrodynamic Simulations
The topology of large scale structure is studied as a function of galaxy type using the genus statistic. In hydrodynamical cosmological CDM simulations, galaxies form on caustic surfaces (Zeldovich pancakes) then slowly drain onto filaments and clusters. The earliest forming galaxies in the simulations (defined as ``el...
1995-06-07
2012-08-27
[ "astro-ph" ]
J. Richard Gott, III, Renyue Cen, and Jeremiah P. Ostriker
astro-ph/9506033
Radiation gasdynamics of planetary nebulae -- VI. The evolution of aspherical planetary nebulae
This paper reports the results of the numerical study of the formation of aspherical Planetary Nebulae through the Generalised Interacting Winds Model, taking into account the effects caused by the evolving central star and fast wind. The results show for the first time that aspherical nebulae do form within the requir...
1995-06-06
2015-06-24
[ "astro-ph" ]
Garrelt Mellema
astro-ph/9506036
A combined X-ray and gravitational lensing study of the massive cooling-flow cluster PKS0745-191
We present spatially-resolved X-ray spectroscopy of the X-ray luminous cluster of galaxies, PKS0745-191, using observations made with the ASCA and ROSAT satellites. The X-ray data measure the density, temperature, and metallicity profiles of the cluster gas and constrain the distribution of mass in the cluster to a rad...
1995-06-06
2015-06-24
[ "astro-ph" ]
S.W. Allen, A.C. Fabian, J.P. Kneib
astro-ph/9506037
UNIFICATION OF THE NEARBY AND PHOTOMETRIC STELLAR LUMINOSITY FUNCTIONS
We introduce a model Galactic field low-mass stellar population that has a proportion of binary systems as observed, with a mass ratio distribution consistent with observational constraints. The model single star and system luminosity function agrees with the nearby and the Malmquist corrected photometric luminosity fu...
1995-06-06
2009-10-28
[ "astro-ph" ]
Pavel Kroupa
astro-ph/9506032
Statistics of optical intraday variability in a complete sample of radio-selected BL Lac objects
We present a study of the intraday variability behaviour of a complete sample of radio-selected BL Lac objects taken from the 1 Jy catalogue. In 28 out of 34 BL Lac objects (82\%) we detected intraday variability. 7 objects were observed during several campaigns. None of them changed its variability behaviour. The duty...
1995-06-06
2016-08-30
[ "astro-ph" ]
Jochen Heidt, Stefan J. Wagner (Landessternwarte Heidelberg, Germany)
astro-ph/9506041
Where is the Dark Matter?
How much dark matter is there in the universe and where is it located? These are two of the most fundamental questions in cosmology. We use in this paper optical and x-ray mass determinations of galaxies, groups, and clusters of galaxies to suggest that most of the dark matter may reside in very large halos around gala...
1995-06-06
2009-10-28
[ "astro-ph" ]
Neta A. Bahcall, Lori M. Lubin & Victoria Dorman (Princeton University Observatory)
astro-ph/9506035
ON THE GEOMETRY OF THE X-RAY EMITTING REGION IN SEYFERT GALAXIES
For the first time, detailed radiative transfer calculations of Comptonized X-ray and gamma-ray radiation in a hot pair plasma above a cold accretion disk are performed using two independent codes and methods. The simulations include both energy and pair balance as well as reprocessing of the X- and gamma-rays by the c...
1995-06-06
2016-08-30
[ "astro-ph" ]
Boris E. Stern (Institute for Nuclear Research, Moscow, Russia) Juri Poutanen (Stockholm Observatory, Sweden), Roland Svensson (Stockholm Observatory, Sweden), Marek Sikora (Nicolaus Copernicus Astronomical Center, Warsaw, Poland), Mitchell C. Begelman (JILA, University of Colorado, Boulder, USA)
astro-ph/9506040
Spin-Statistics Connexion, Neutrinos, and Big Bang Nucleosynthesis
We show how the $^4$He-abundance in the early Universe can be used to demonstrate that macroscopic samples of neutrinos in thermal equilibrium are indeed distributed according to Fermi-Dirac statistics.
1995-06-06
2011-05-23
[ "astro-ph", "hep-ph" ]
L. Cucurull, J.A. Grifols and R. Toldr\`a
astro-ph/9506042
DYNAMICS OF THE GALACTIC GLOBULAR CLUSTER NGC 3201
B,V CCD frames have been used to derive surface brightness profiles for NGC 3201 out to ~18 arcmin. A total of 857 radial velocities with median precision ~1 km/s for 399 member giants have been used to trace the velocity dispersion profile out to 32' (the approximate tidal radius from fits of single-mass, isotropic Ki...
1995-06-06
2009-10-28
[ "astro-ph" ]
Patrick Cote, Douglas L. Welch, Philippe Fischer and K. Gebhardt
astro-ph/9506031
Analysis of Non-Linear Mode Coupling of Cosmological Density Fluctuations by the Pseudo-Spectral Method
The pseudo-spectral method is proposed for following the evolution of density and velocity fluctuations at the weakly non-linear stage in the expanding universe with a good accuracy. In this method, the evolution of density and velocity fluctuations is integrated in the Fourier Space with using FFT. This method is very...
1995-06-06
2017-02-01
[ "astro-ph" ]
Naoteru Gouda
astro-ph/9506038
VLBI Observations of a Complete Sample of Radio Galaxies V. 3C346 and 4C31.04: two Unusual CSS Sources
We present observations at 1.7 and 8.4 GHz of two Compact Steep Spectrum (CSS) sources from a complete sample of low-intermediate power radio galaxies. 3C346 shows an asymmetric structure with a one-sided ``jet'' and ``hot spot''. Present observations suggest that the classification of this source as a CSS is inappropr...
1995-06-06
2009-10-28
[ "astro-ph" ]
W.D. Cotton, L. Feretti, G. Giovannini, T. Venturi, L. Lara, J. Marcaide and A. E. Wehrle
astro-ph/9506034
VLBI Observations of Low Power Radio Galaxies
The parsec scale properties of low power radio galaxies are reviewed here, using the available data on 12 FR I galaxies. The most frequent radio structure is an asymmetric parsec-scale morphology, i.e. core and one-sided jet. It is shared by 9 (possibly 10) of the 12 mapped radio galaxies. One (possibly 2) of the other...
1995-06-06
2007-05-23
[ "astro-ph" ]
G. Giovannini, W.D. Cotton, L. Feretti, L. Lara, T.Venturi, J.M. Marcaide
astro-ph/9506043
A Near-Infrared Search for Line Emission from Protogalaxies Using the W. M. Keck Telescope
We present the first results from a near-infrared narrow-band search for primeval galaxies (PGs) using the Keck 10~m telescope. We have targeted our fields for three QSOs and one radio galaxy at redshifts $z = 2.28$ to $4.70$. We selected narrow-band filters in the $K$-band centered on strong emision lines at the redsh...
1995-06-06
2009-10-28
[ "astro-ph" ]
M. A. Pahre and S. G. Djorgovski (Palomar Observatory, Caltech)
astro-ph/9506039
Detection of dust in the most distant known radiogalaxy
A search for millimetric continuum emission from eight optically-selected, radio-quiet quasars and a radiogalaxy with 3.7 < z < 4.3, has been undertaken using a highly sensitive 7-channel bolometer on the IRAM 30-m Millimetre Radio Telescope. Detections of a potentially dust-rich quasar, and of 8C1435+635, the most dis...
1995-06-06
2016-06-08
[ "astro-ph" ]
R. J. Ivison (Royal Observatory, Edinburgh)
astro-ph/9506024
Influence of the symmetry energy on the birth of neutron stars and supernova neutrinos
We study the influence of the symmetry energy of the equation of state on the thermal evolution of protoneutron stars and the properties of supernova neutrinos by the numerical simulations after the protoneutron stars are formed. As for the equation of state (EOS) of nuclear matter, we take two EOS's with different sym...
1995-06-05
2011-05-23
[ "astro-ph", "nucl-th" ]
K. Sumiyoshi, H. Suzuki, H. Toki
astro-ph/9506029
A ROSAT Search for X-ray Emission from Quasar Host Clusters
We report the results of a search for X-ray emission from quasar host clusters at moderate redshift using the {\sl ROSAT} HRI. We detect no emission from the host clusters of 3C~263 (z=0.646) and PKS~2352-34 (z=0.706) to 3$\sigma$\ limits of 3.26 and 2.86 $\times$10$^{44}$\ ergs~s$^{-1}$ respectively (H$_o$=50, q$_o$=1...
1995-06-05
2009-10-28
[ "astro-ph" ]
Patrick B. Hall (University of Arizona), Erica Ellingson (University of Colorado), Richard F. Green (KPNO), and Howard Yee (University of Toronto)
astro-ph/9506026
Tidal Shear on Density Perturbations and Galaxy Formation
The strenth of the tidal shear produced by the large-scale density field acting on primordial density perturbations is calculated in power law models. It is shown that the large-scale tidal field could, strongly affect the morphology, orientation and angular momentum aquisition of density peaks possibly playing a role ...
1995-06-05
2007-05-23
[ "astro-ph" ]
Alejandro Gonzalez (S. Instituto Nacional de Astrofisica, Optica y Elec)
astro-ph/9506025
Application of the spectral subtraction technique to the CaII H & K and H$\epsilon$ lines in a sample of chromospherically active binaries
We present new spectroscopic observations in the Ca~{\sc ii} H \& K line region for a sample of 28 chromospherically active binary systems (RS$~$CVn and BY$~$Dra classes), with different activity levels. By using the spectral subtraction technique (subtraction of a synthesized stellar spectrum constructed from referenc...
1995-06-05
2007-05-23
[ "astro-ph" ]
D. Montes, E. De Castro, M.J. Fernandez-Figueroa, M. Cornide
astro-ph/9506030
High Resolution Infrared Imaging of FSC10214+4724: Evidence for Gravitational Lensing
We present near--infrared observations of the ultraluminous high-redshift (z=2.286) IRAS source FSC 10214+4724 obtained in 0.''4 seeing at the W. M. Keck telescope. These observations show that FSC 10214+4724 consists of a highly symmetric circular arc centered on a second weaker source. The arc has an angular extent o...
1995-06-05
2009-10-28
[ "astro-ph" ]
James R. Graham and Michael C. Liu (Astronomy Department, University of California, Berkeley)
astro-ph/9506028
Measuring q_0 from the Distortion of Voids in Redshift Space
Because the transformation from distance to redshift is nonlinear, maps in redshift space become increasingly distorted as the redshift z becomes greater. As noted by Alcock \& Paczy\'nski (1979), observed redshift distortions can be used to estimate the deceleration parameter $q_0$. If $q_0$ is greater than -1, voids ...
1995-06-05
2009-10-28
[ "astro-ph" ]
Barbara Ryden (Ohio State University)
astro-ph/9506023
Violation of the inverse square law by the emissions of supersonically and superluminally moving volume sources
The generally familiar notion that the conservation of energy requires the intensity of the radiation generated by a localized finite-duration source to decay like the inverse square of the distance from the source is not necessarily true. In this paper, we identify physically tenable sources of acoustic and electromag...
1995-06-05
2009-09-25
[ "astro-ph" ]
H. Ardavan, J. E. Ffowcs Williams
astro-ph/9506027
The Age of the Universe
It is found that the ages of the most metal-poor Galactic globular clusters are probably around 18 Gyr. On the other hand a Hubble parameter of 82 +/- 8 km/sec/Mpc (in conjunction with the standard Einstein-de Sitter model with an Omega =1 and Lambda =0) yields and age of the Universe of about 8 Gyr. Some possible reas...
1995-06-05
2007-05-23
[ "astro-ph" ]
Sidney van den Bergh
astro-ph/9506021
PULSARS WITH STRONG MAGNETIC FIELDS: POLAR GAPS, BOUND PAIR CREATION AND NONTHERMAL LUMINOSITIES
Modifications to polar-gap models for pulsars are discussed for the case where the surface magnetic field, $B_\S$, of the neutron star is strong. For $B\ga4\times10^8\rm\,T$, the curvature $\gamma$-quanta emitted tangentially to the curved force lines of the magnetic field are captured near the threshold of bound pair ...
1995-06-04
2015-06-24
[ "astro-ph" ]
V.V. Usov and D.B. Melrose
astro-ph/9506022
Correlation function as a measure of the structure
Geometrical model of structure of the universe is examined to obtain analytical expression for the two points nonlinear correlation function. According to the model the objects (galaxies) are concentrated into two types of structure elements - filaments and sheets. We considered the filaments ( similar to galaxy filame...
1995-06-04
2007-05-23
[ "astro-ph" ]
O. Buryak & A. Doroshkevich
astro-ph/9506020
IMAGING SPECTROPHOTOMETRY OF MARKARIAN 573
Narrow-band emission-line and continuum images obtained in subarcsecond seeing conditions are presented for the Seyfert~2 galaxy, Markarian 573. Images in the emission-lines of [\oi], [\oii], [\oiii], [\sii], and \halpha+[\nii] are used to measure the structure and excitation in the extended emission regions surroundin...
1995-06-03
2009-10-28
[ "astro-ph" ]
Richard Pogge (Ohio State) and Michael De Robertis (York Univ)
astro-ph/9506017
Inflation with $\Omega \not = 1$
We discuss various models of inflationary universe with $\Omega \not = 1$. A homogeneous universe with $\Omega > 1$ may appear due to creation of the universe "from nothing" in the theories where the effective potential becomes very steep at large $\phi$, or in the theories where the inflaton field $\phi$ nonminimally ...
1995-06-03
2016-08-30
[ "astro-ph", "gr-qc", "hep-ph", "hep-th" ]
Andrei Linde and Arthur Mezhlumian
astro-ph/9506019
A study of the core of the Shapley Concentration: II. ROSAT observation of A3558
We present the results of a pointed ROSAT PSPC observation of the cluster A3558 which is part of the core of the Shapley Concentration. The X-ray brightness distribution can be fitted as the sum of an elliptical King law, with a major core radius of about 0.20 Mpc and an axial ratio 0.72, and a Gaussian central source ...
1995-06-03
2007-05-23
[ "astro-ph" ]
S.Bardelli, E.Zucca, A.Malizia, G.Zamorani, R.Scaramella, G.Vettolani
astro-ph/9506018
Relaxation processes in one-dimensional self-gravitating many-body systems
Though one dimensional self-gravitating $N$-body systems have been studied for three decade, the nature of relaxation was still unclear. There were inconsistent results about relaxation time; some initial state relaxed in the time scale $T\sim N\,t_c$, but another state did not relax even after $T\sim N^2\,t_c$, where ...
1995-06-03
2009-10-28
[ "astro-ph" ]
Toshio Tsuchiya (National Astronomical Observatory, Mitaka, Japan), Naoteru Gouda (Department of Earth and Space Science, Osaka University, Japan) and Tetsuro Konishi (Department of Physics, Nagoya University, Japan)
astro-ph/9506014
The role of cooling flows in galaxy formation
The present structure of galaxies is governed by the radiative dissipation of the gravitational and supernova energy injected during formation. A crucial aspect of this process is whether the gas cools as fast as it falls into the gravitational potential well. If it does then rapid normal star formation is assumed to e...
1995-06-02
2015-06-24
[ "astro-ph" ]
P.E.J. Nulsen, A.C. Fabian
astro-ph/9506011
Structure Formation with a Decaying Mev Tau Neutrino and a Kev Majoron
We consider the scenario of large scale structure formation with tau neutrino with mass in the MeV range and lifetime of order of years which decays into a massive majoron with KeV mass. The latter are the present-day cold dark matter particles. In contrast to the usual collisionless dark matter, the majorons have a re...
1995-06-02
2007-05-23
[ "astro-ph", "hep-ph" ]
A.D. Dolgov, S. Pastor and J.W.F. Valle
astro-ph/9506016
MACHO COLLABORATION SEARCH FOR BARYONIC DARK MATTER VIA GRAVITATIONAL MICROLENSING
Results are presented from the MACHO collaboration gravitational microlensing search. The experiment and the nearly 50 microlensing events that have been detected are described. Limits on the baryonic content of the halo are given, as are estimates of the Macho contribution to the dark halo. Optical depths toward the b...
1995-06-02
2007-05-23
[ "astro-ph", "hep-ph" ]
K. Griest, C. Alcock, R.A. Allsman, T.S. Axelrod, D.P. Bennett, K.H. Cook, K.C. Freeman, J. Guern, M. Lehner, S.L. Marshall, S. Perlmutter, B.A. Peterson, M.R. Pratt, P.J. Quinn, A.W. Rodgers, C.W. Stubbs, W. Sutherland, D. Welch (The MACHO Collaboration)
astro-ph/9506015
Neutrino decoupling in the early Universe
A calculation of neutrino decoupling in the early Universe, including full Fermi-Dirac statistics and electron mass dependence in the weak reaction rates, is presented. We find that after decoupling, the electron neutrinos contribute 0.83\% more to the relativistic energy density than in the standard scenario, where ne...
1995-06-02
2010-01-15
[ "astro-ph", "hep-ph" ]
Steen Hannestad and Jes Madsen
astro-ph/9506012
Existence and interpretation of smooth cosmic-ray dominated shock structures in supernova remnants
Studies of energetic particle acceleration at collisionless shocks by the diffusive shock acceleration process indicate that completely smooth cosmic ray dominated shock structures are possible. The existence of these is discussed and conditions for their existence derived. It is shown that such solutions cannot domina...
1995-06-02
2011-05-23
[ "astro-ph" ]
Drury L O'C, V\"olk H J and Berezhko E G
astro-ph/9506013
NEUTRINO SPIN AND FLAVOUR CONVERSION AND OSCILLATIONS IN MAGNETIC FIELD
A review of the neutrino conversion and oscillations among the two neutrino species (active and sterile) induced by strong twisting magnetic field is presented and implications to neutrinos in neutron star, supernova, the Sun and interstellar galactic media are discussed. The ``cross-boundary effect" (CBE) (i.e., a pos...
1995-06-02
2008-02-03
[ "astro-ph" ]
A.M.Egorov, G.G.Likhachev, A.I.Studenikin
astro-ph/9506010
QSO HOST GALAXIES AT Z=2.3
Images are discussed of six QSOs at z=2.3, one QSO-like IRAS source at z=2.3, and one QSO at z=1.1, taken with resolution 0.6 to 0.9 arcsec. Five of the QSOs are radio-quiet. All QSOs except one are just resolved, while the IRAS source has definite structure. In some cases, part of the QSO fuzz appears to be a close co...
1995-06-02
2009-10-28
[ "astro-ph" ]
J.B. Hutchings
astro-ph/9506002
Supersonic Turbulence and the Fragmentation of a Cold Medium
The role played by velocity fields in the fragmentation of a cold medium and in the formation of protostars is studied. The velocity field is modeled with a compressible turbulent flow. A supersonic turbulent velocity field can fragment the medium into clumps of mass smaller than a local Jeans' mass, and therefore st...
1995-06-01
2015-06-24
[ "astro-ph" ]
Paolo Padoan (Theoretical Astrophysics Center - Copenhagen - Denmark)
astro-ph/9506006
Physical constraints on the halo mass function
We analyse the effect of two relevant physical constraints on the mass multiplicity function of dark matter halos in a Press--Schechter type algorithm. Considering the random--walk of linear Gaussian density fluctuations as a function of the smoothing scale, we simultaneously i) account for mass semi--positivity and ii...
1995-06-01
2015-06-24
[ "astro-ph" ]
C. Porciani, F. Ferrini, F. Lucchin and S. Matarrese
astro-ph/9506003
The epoch of structure formation in blue mixed dark matter models
Recent data on the high--redshift abundance of damped Ly$\alpha$ systems are compared with theoretical predictions for `blue' (i.e. $n>1$) Mixed Dark Matter models. The results show that decreasing the hot component fraction $\Omega_\nu$ and/or increasing the primordial spectral index $n$ implies an earlier epoch of co...
1995-06-01
2015-06-24
[ "astro-ph" ]
Stefano Borgani, Francesco Lucchin, Sabino Matarrese and Lauro Moscardini
astro-ph/9506001
RR LYRAE VARIABLE STARS: PULSATIONAL CONSTRAINTS RELEVANT TO THE OOSTERHOFF CONTROVERSY
A solution to the old Oosterhoff controversy is proposed on the basis of a new theoretical pulsational scenario concerning RR Lyrae cluster variables (Bono and coworkers). We show that the observed constancy of the lowest pulsation period in both Oosterhoff type I (OoI) and Oosterhoff type II (OoII) prototypes (M3, M15...
1995-06-01
2009-10-28
[ "astro-ph" ]
G. Bono, F. Caputo, V. Castellani and M. Marconi
astro-ph/9506004
The Universal Rotation Curve of Spiral Galaxies: I. the Dark Matter Connection
We use a homogeneous sample of about 1100 rotation curves (RCs) and relative surface photometry to investigate (out to 2 optical radii and over 6 mag) the main mass structure properties of spirals. We confirm the strong dependence on luminosity for both the profile and the amplitude of RCs. Spiral RCs show the striking...
1995-06-01
2015-06-24
[ "astro-ph" ]
M.Persic, P.Salucci, and F.Stel
astro-ph/9506007
Mass loss in metal deficient Red Giants
We investigate the final fate of metal deficient (MD) H burning Red Giants under various assumptions about the amount of mass loss. Adopting a metallicity Z= 10^(-8), we follow the evolution of 0.8 Mo models from the Main Sequence phase till the onset of the He flash or the final cooling as a He White Dwarf, according ...
1995-06-01
2011-05-23
[ "astro-ph" ]
V. Castellani and M. Romaniello (Dip. Fisica - Pisa --- Scuola Normale Superiore - Pisa)
astro-ph/9506009
On the Injection Energy Distibution of Ultra-High-Energy Cosmic Rays
We investigate the injection spectrum of ultra-high-energy (>10^{15} eV) cosmic rays under the hypotheses that (1) these cosmic rays are protons and (2) the sources of these cosmic rays are extra-galactic and are homogeneously distributed in space. The most puzzling aspect of the observed ultra-high-energy cosmic ray s...
1995-06-01
2009-10-28
[ "astro-ph" ]
James Geddes, Theodore C. Quinn, and Robert M. Wald (University of Chicago)
astro-ph/9506005
On the interpretation of clustering from the angular APM Galaxy Survey
We analyze the uncertainties in the amplitudes of the spatial correlation functions estimated from angular correlations in a sample from the APM Galaxy Survey, with $b_J=17-20$. We model the uncertainties in the selection function and in the evolution of clustering. In particular we estimate $\sigma_8^{APM}$, the rms g...
1995-06-01
2009-10-28
[ "astro-ph" ]
Enrique Gazta\~naga
astro-ph/9505148
THE POLARIZED SPECTRUM OF THE FE II-RICH BAL QSO, IRAS 07598+6508
We present IUE spectrophotometry and optical spectropolarimetry of the ultraluminous, extreme FeII-emitting QSO IRAS 07598+6508. We find broad absorption troughs from high- and low-ionization species, showing that this object is a member of the class of rare low-ionization BAL QSOs. Compared with non-BAL QSOs, the spec...
1995-06-01
2009-10-28
[ "astro-ph" ]
Dean C. Hines and Beverley J. Wills (University of Texas at Austin)
astro-ph/9506008
ON THE MEASUREMENT OF A COSMOLOGICAL DIPOLE IN THE PHOTON NUMBER COUNTS OF GAMMA-RAY BURSTS
If gamma-ray bursts are cosmological or in a halo distribution their properties are expected to be isotropic (at least to 1st order). However, our motion with respect to the burst parent population (whose proper frame is expected to be that of the Cosmic Microwave Background (CMB), or that of a static halo) will cause ...
1995-06-01
2009-10-28
[ "astro-ph" ]
C.A. Scharf, K. Jahoda and E. Boldt (NASA Goddard Space Flight Center)
astro-ph/9505146
The gamma-ray burst GB 920622
We have analyzed the Ulysses, BATSE, and COMPTEL spectral data from the $\gamma$-ray burst of June 22, 1992 (GB 920622). COMPTEL data reveal a hard to soft evolution within the first pulse of the burst, while the mean hardness ratios of the three pulses are the same. Unlike the single instrument spectra, the composite ...
1995-05-31
2016-08-15
[ "astro-ph" ]
J. Greiner, M. Sommer, N. Bade, G.J. Fishman, L.O. Hanlon, K. Hurley, R.M. Kippen, C. Kouveliotou, R. Preece, J. Ryan, V. Sch\"onfelder, O.R. Williams, C. Winkler, M. Boer, M. Niel
astro-ph/9505144
Radio-optical Orientation of Elliptical Galaxies
Present knowledge of the distribution of the angle between major optical and radio axes of early-type galaxies is reviewed. While brightest galaxies in Abell clusters show a bimodal distribution of this angle, with both parallel and vertical alignment, ellipticals in general only show a weak preference for vertical ali...
1995-05-31
2007-05-23
[ "astro-ph" ]
Heinz J. Andernach (IUE Observatory, Spain)
astro-ph/9505143
Small scale CMB fluctuations as a probe of the mass of Dark Matter particles
The CMB anisotropy on arc second range is examined to test the power spectrum of perturbations in the small scale region and, in particular, to estimate the mass of dominant dark matter particles. It is shown that for the simplest evolutionary history with standard recombination, three and four beam observations could ...
1995-05-31
2009-10-28
[ "astro-ph" ]
Andrei G. Doroshkevich and Raffaella Schneider
astro-ph/9505147
QUASARS AND LARGE SCALE STRUCTURE OF THE UNIVERSE
The majority of bright distant quasars $(z {}^{>}_{\sim} 1)$ may form in massive mergers appearing in compact galaxy groups in/and young clusters. The expected tests are (i) large correlation signal for medium-$z$ QSOs $(1 < z < 2)$ and (ii) direct search for quasar groups (QGs) indicating positions of distant pre-supe...
1995-05-31
2009-10-28
[ "astro-ph" ]
V.N.Lukash (Astro Space Center, Lebedev Physical Institute, Moscow)
astro-ph/9505145
Search for GRB counterparts
A state-of-the-art review is given on the search for counterparts of $\gamma$-ray bursts. Particular emphasis is put on the search for flaring counterparts, i.e. emission during or shortly after the gamma-ray emission. With BACODINE working now for nearly one year, some of the highlights of the herewith triggered follo...
1995-05-31
2009-10-28
[ "astro-ph" ]
J. Greiner
astro-ph/9505137
Lunar Occultation of MACHOs
Lunar occultation can be used to measure the proper motions of some of the long time scale microlensing events, $t_{e} \gsim 70$ days, now being detected toward the Galactic bulge. The long events are difficult to explain within the context of standard models of the mass distribution and dynamics of the Galaxy. Han & G...
1995-05-30
2009-10-28
[ "astro-ph" ]
Cheongho Han, Vijay K. Narayanan, and Andrew Gould
astro-ph/9505142
Filament Statistics: A Quantitative Comparison of Cold + Hot and Cold Dark Matter Cosmologies with CfA1 Data
A new class of geometric statistics for analyzing galaxy catalogs is presented. {\it Filament statistics} quantify filamentarity and planarity in large scale structure in a manner consistent with catalog visualizations. These statistics are based on sequences of spatial links which follow local high-density structures....
1995-05-30
2007-05-23
[ "astro-ph" ]
Romeel Dav\'e (UCSC), Doug Hellinger (UCSC), Richard Nolthenius (UCSC), Joel Primack (UCSC), Anatoly Klypin (NMSU)
astro-ph/9505140
Scalar Electrodynamics and Primordial Magnetic Fields
A primordial magnetic field may be generated during an inflationary period if conformal invariance is broken. We reexamine and generalize previous results about the magnetic field produced by couplings of the form $R^n F_{\mu\nu}F^{\mu\nu}$. We show that the amplitude of the magnetic field depends strongly on $n$. For ...
1995-05-30
2009-10-28
[ "astro-ph", "gr-qc" ]
F.D. Mazzitelli and F.M. Spedalieri
astro-ph/9505135
Spectral Indices in Cooling Flow Galaxies: Evidence for Star Formation
Through the study of two absorption spectral features in the optical range (Mg2 and the 4000 A break), we find evidence for star formation in the inner regions of cooling-flow galaxies. The application of simple stellar population models reveals that the measured indices are explained if a relatively small fraction of ...
1995-05-30
2015-06-24
[ "astro-ph" ]
N. Cardiel, J. Gorgas, and A. Aragon-Salamanca
astro-ph/9505141
Cosmic Ray Positrons at High Energies: A New Measurement
We present a new measurement of the cosmic-ray positron fraction e+/(e+ + e-) obtained from the first balloon flight of the High Energy Antimatter Telescope (HEAT). Using a magnet spectrometer combined with a transition radiation detector, an electromagnetic calorimeter, and time-of-flight counters we have achieved a h...
1995-05-30
2012-08-27
[ "astro-ph" ]
HEAT Collaboration (S.W. Barwick, J.J. Beatty, C.R. Bower, C. Chaput, S. Coutu, G. de Nolfo, D. Ficenec, J. Knapp, D.M. Lowder, S. McKee, D. Muller, J.A. Musser, S.L. Nutter, E. Schneider, S.P. Swordy, K.K. Tang, G. Tarle, A.D. Tomasch, E. Torbet)
astro-ph/9505136
SIMULATING LARGE-SCALE STRUCTURE FORMATION FOR BSI POWER SPECTRA
A double inflationary model provides perturbation spectra with enhanced power at large scales (Broken Scale Invariant perturbations -- BSI), leading to a promising scenario for the formation of cosmic structures. We describe a series of high-resolution PM simulations with a model for the thermodynamic evolution of bary...
1995-05-30
2007-05-23
[ "astro-ph" ]
V. Mueller
astro-ph/9505139
The Cosmic Background Radiation, Snowmass Workshop
Observations of the Cosmic Microwave background have provided many of the most powerful constraints we have on cosmology and events in the early universe. The spectrum and isotropy of CBR have long been a pillar of Big Bang models. The discovery of low levels on anisotropy has provided new information and tools for our...
1995-05-30
2016-08-30
[ "astro-ph" ]
George F. Smoot (Berkeley)
astro-ph/9505138
COMPARATIVE STUDY OF A [WC 6] NUCLEUS WITH OTHER EMISSION-LINES NUCLEI OF PLANETARY NEBULAE
The central star (CSPN) of the planetary nebula M 1-25 (PN G 4.9+4.9) is classified as a [WC 6] star, the only CSPN of this subclass known at this time. A comparison with the other emission-lines CSPN (the [WC]-class and the 'weak emission-lines stars' or {\em wels}-class) shows that (1) the characteristics of this [WC...
1995-05-30
2007-05-23
[ "astro-ph" ]
A. Acker, S. K. Gorny and F. Cuisinier
astro-ph/9505133
The ESO Key-Programme ``A Homogeneous Bright QSO Survey'' - I The Methods and the ``Deep'' Fields
This is the first paper in a series aimed at defining a statistically significant sample of QSOs in the range $ 15 < B < 18.75$ and $ 0.3 < z < 2.2$. The selection is carried out using direct plates obtained at the ESO and UK Schmidt Telescopes, scanned with the COSMOS facility and searched for objects with an ultravio...
1995-05-29
2007-05-23
[ "astro-ph" ]
S. Cristiani, F. La Franca, P. Andreani, A. Gemmo, P. Goldschmidt, L. Miller, R. Vio, C. Barbieri, L. Bodini, A. Iovino, M. Lazzarin, R. Clowes, H. MacGillivray, Ch. Gouiffes, C. Lissandrini, A. Savage
astro-ph/9505134
Magnetic Monopoles as the Highest Energy Cosmic Ray Primaries
We suggest that the highest energy $ \gsim 10^{20} eV$ cosmic ray primaries may be relativistic magnetic monopoles. Motivations for this hypothesis are that conventional primaries are problematic, while monopoles are naturally accelerated to $E \sim 10^{20} eV$ by galactic magnetic fields. By matching the cosmic monopo...
1995-05-29
2009-10-28
[ "astro-ph", "hep-ph" ]
Thomas W. Kephart and Thomas J. Weiler
astro-ph/9505132
THE CLUSTERING OF QUASARS
We have investigated the spatial distribution of quasars and its relationship with redshift by using the two-point correlation function, the variance of cell counts and the conditional density as a function of redshift. By comparing our results with those found by other authors we conclude that quasars have a correlati...
1995-05-29
2007-05-23
[ "astro-ph" ]
P. Andreani, S. Cristiani and F. La Franca (Dip.Astron. Univ.Padova)
astro-ph/9505131
CLUSTERING PROPERTIES OF THE LY$\alpha$ CLOUDS
The spectra of the QSOs PKS2126-158 ($z_{em}=3.27$) and Q0055-269 ($z_{em}=3.66$) have been observed at high resolution ($2.2 - 2.7 \times 10^4$). Significant clustering, with $\xi \simeq 1$ at $\Delta v=100$ km s$^{-1}$, is detected in both cases for lines with $\log N_{HI} \geq 13.8$. A similar result is obtained ana...
1995-05-29
2007-05-23
[ "astro-ph" ]
S. Cristiani, S. D'Odorico, V. D'Odorico, A. Fontana, E. Giallongo, S. Savaglio
astro-ph/9505130
The Microlensing and Halo Models of the Galaxy
We investigated the dependence of the optical depth $\tau$ of the microlensing events on model parameters of the Galactic halo. We only consider Galactic mass models in which the rotation curve inside the Sun is compatible with the observation and LMC is bound to the Galaxy. It is found that $\tau$ varies up to a facto...
1995-05-29
2015-06-24
[ "astro-ph" ]
Yukitoshi Kan-ya, Ryoichi Nishi and Takashi Nakamura
astro-ph/9505129
CCD PHOTOMETRY OF VARIABLE STARS IN THE GLOBULAR CLUSTER RU 106
BV photometry is presented for 12 RR Lyr variables discovered in the presumably young galactic globular cluster Ruprecht 106. All variables are type RRab, and their periods span a narrow range from 0.574 to 0.652 day. We report also on the discovery of 3 SX Phe variables among the cluster blue stragglers. A likely back...
1995-05-27
2009-10-28
[ "astro-ph" ]
Janusz Kaluzny, Wojciech Krzeminski, Beata Mazur
astro-ph/9505125
Structure of Primordial Gravitational Waves Spectrum in a Double Inflationary Model
The gravitational waves (GW) background generated in a double inflationary model, with two scalar fields mutually interacting through gravity only, and its relative contribution $T/S$ to large-angle temperature fluctuations of the relic microwave background are investigated in detail. The relation between $T/S$ and the...
1995-05-27
2009-10-28
[ "astro-ph", "gr-qc", "hep-th" ]
David Polarski and Alexei A. Starobinsky
astro-ph/9505128
ARE THE NEARBY AND PHOTOMETRIC STELLAR LUMINOSITY FUNCTIONS DIFFERENT?
The stellar luminosity function derived from the sample of stars within 5.2--20~pc is the nearby luminosity function. The luminosity function obtained from deep low spatial resolution surveys to distances of typically 100--200~pc is the photometric luminosity function. We obtain and tabulate a best estimate of the pare...
1995-05-27
2009-10-28
[ "astro-ph" ]
Pavel Kroupa
astro-ph/9505126
A study of the Orion cometary cloud L1616
With its cometary appearance and a reflection nebula near its edge facing some bright Orion stars, the Lynd's cloud L1616 shows ample evidence for being affected by one or more of these massive stars. To estimate its mass and star formation efficiency as well as to determine if it is gravitationally bound, we mapped th...
1995-05-27
2015-06-24
[ "astro-ph" ]
B.Ramesh
astro-ph/9505127
AN IMPROVED MEASURE OF QUASAR ORIENTATION
Radio core dominance, usually measured by R, the rest frame ratio of core to lobe flux density, has been used as an indicator of Doppler boosting of quasars' radio jets and hence the inclination of the central engine's spin axis to the line of sight. The use of lobe flux density as a means of normalizing the boosted co...
1995-05-27
2009-10-28
[ "astro-ph" ]
Beverley J. Wills and M. S. Brotherton (Univ. of Texas at Austin, USA)
astro-ph/9505122
Optical structure and polarization of the western hot spot of Pictor A
HST images of the western hot spot of the nearby FRII radio galaxy Pictor A resolve the hot spot into an amorphous region of highly polarized wisps. The high polarization (>~ 50%) indicates that the optical emission is synchrotron radiation and that the magnetic field structure has been well resolved. The magnetic fiel...
1995-05-26
2016-08-30
[ "astro-ph" ]
R.C. Thomson, P. Crane, C.D. Mackay
astro-ph/9505120
The Doppler Peaks from Cosmic Texture
We compute the angular power spectrum of temperature anisotropies on the microwave sky in the cosmic texture theory, with standard recombination assumed. The spectrum shows `Doppler' peaks analogous to those in scenarios based on primordial adiabatic fluctuations such as `standard CDM', but at quite different angular s...
1995-05-26
2016-08-24
[ "astro-ph" ]
R.G. Crittenden and N.G. Turok (Princeton University)