560 research outputs found
The Discovery of a High Redshift X-ray Emitting QSO Very Close to the Nucleus of NGC 7319
A strong X-ray source only 8" from the nucleus of the Sy2 galaxy NGC 7319 in
Stephan's Quintet has been discovered by Chandra. We have identified the
optical counterpart and show it is a QSO with . It is also a ULX
with . From the optical spectra of the QSO
and interstellar gas in the galaxy (z = .022) we show that it is very likely
that the QSO and the gas are interacting.Comment: 8 figures, 5 color, minimized ps siz
The dryout region in frictionally heated sliding contacts
Some conditions under which boiling and two-phase flow can occur in or near a wet sliding contact are determined and illustrated. The experimental apparatus consisted of a tool pressed against an instrumented slider plate and motion picture sequences at 4000 frames/sec. The temperature and photographic data demonstrated surface conditions of boiling, drying, trapped gas evolution (solutions), and volatility of fluid mixture components. The theoretical modeling and analysis are in reasonable agreement with experimental data
Evidence for Intrinsic Redshifts in Normal Spiral Galaxies
The Tully-Fisher Relationship (TFR) is utilized to identify anomalous
redshifts in normal spiral galaxies. Three redshift anomalies are identified in
this analysis: (1) Several clusters of galaxies are examined in which late type
spirals have significant excess redshifts relative to early type spirals in the
same clusters, (2) Galaxies of morphology similar to ScI galaxies are found to
have a systematic excess redshift relative to the redshifts expected if the
Hubble Constant is 72 km s-1 Mpc-1, (3) individual galaxies, pairs, and groups
are identified which strongly deviate from the predictions of a smooth Hubble
flow. These redshift deviations are significantly larger than can be explained
by peculiar motions and TFR errors. It is concluded that the redshift anomalies
identified in this analysis are consistent with previous claims for large
non-cosmological (intrinsic) redshifts.Comment: Accepted for publication at Astrophysics&Space Science. 36 pages
including 8 tables and 7 figure
Time dilation in the supernova light curve and the variable mass hypothesis
The recently reported time dilation effect in Type Ia supernova SN 1995K has been claimed to rule out the static universe model of Narlikar & Arp. It is shown here that the variable mass hypothesis which accounts for the redshift phenomenon in the above static universe model does indeed predict the observed effect and that there is no conflict between the data of Leibundgut et al. and the predictions of this model
The Wolf effect and the Redshift of Quasars
We consider a simple model, based on currently accepted models for active
galactic nuclei, for a quasi-stellar object (QSO or ``quasar'') and examine the
influence that correlation- induced spectral changes (``The Wolf Effect'') may
have upon the redshifts of the optical emission lines.Comment: 13 pages, 3 figures. To be published in J. European Optical Soc. A:
Pure and Applied Optic
Globular Clusters as Candidates for Gravitational Lenses to Explain Quasar-Galaxy Associations
We argue that globular clusters (GCs) are good candidates for gravitational
lenses in explaining quasar-galaxy associations. The catalog of associations
(Bukhmastova 2001) compiled from the LEDA catalog of galaxies (Paturel 1997)
and from the catalog of quasars (Veron-Cetty and Veron 1998) is used. Based on
the new catalog containing 8382 pairs, we show that one might expect an
increased number of GCs around irregular galaxies of types 9 and 10 from the
hypothesis that distant compact sources are gravitationally lensed by GCs in
the halos of foreground galaxies. The King model is used to determine the
central surface densities of 135 GCs in the Milky Way. The distribution of GCs
in central surface density was found to be lognormal.Comment: 22 pages, 4 figure
Intrinsic Redshifts and the Tully-Fisher Distance Scale
The Tully-Fisher relationship (TFR) has been shown to have a relatively small
observed scatter of ~ +/-0.35 mag implying an intrinsic scatter < +/-0.30 mag.
However, when the TFR is calibrated from distances derived from the Hubble
relation for field galaxies scatter is consistently found to be +/-0.64 to
+/-0.84 mag. This significantly larger scatter requires that intrinsic TFR
scatter is actually much larger than +/-0.30 mag, that field galaxies have an
intrinsic TFR scatter much larger than cluster spirals, or that field galaxies
have a velocity dispersion relative to the Hubble flow in excess of 1000 km
s-1. Each of these potential explanations faces difficulties contradicted by
available data and the results of previous studies. An alternative explanation
is that the measured redshifts of galaxies are composed of a cosmological
redshift component predicted from the value of the Hubble Constant and a
superimposed intrinsic redshift component previously identified in other
studies. This intrinsic redshift component may exceed 5000 km s-1 in individual
galaxies. In this alternative scenario a possible value for the Hubble Constant
is 55-60 km s-1 Mpc-1.Comment: 15 pages, Astrophysics&Space Science - Accepted for publicatio
A bias in optical observations of high redshift luminous infrared galaxies
We present evidence for the dramatically different morphology between the
rest frame UV and 7micron mid-IR emission of VV114 and Arp299, two nearby (z~0)
violently interacting infrared luminous galaxies (LIRGs). Nearly all LIRGs are
interacting systems and it is currently accepted that they dominate the IR
emission at z>1. Luminous IR galaxies located at z=1-2 could easily be detected
as unresolved sources in deep optical/near-IR ground based surveys, as well as
in upcoming 24micron surveys with the Space Infrared Telescope Facility. We
demonstrate that the spatial resolution of these surveys will result in
blending of the emission from unresolved interacting components. An increased
scatter will thus be introduced in the observed optical to mid-IR colors of
these galaxies, leading to a systematic underestimation of their dust content.Comment: To appear in the Astrophysical Journal Letters (4 pages 1 figure
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