5,977 research outputs found
Supergravity Tensor Calculus in 5D from 6D
Supergravity tensor calculus in five spacetime dimensions is derived by
dimensional reduction from the d=6 superconformal tensor calculus. In
particular, we obtain an off-shell hypermultiplet in 5D from the on-shell
hypermultiplet in 6D. Our tensor calculus still retains the dilatation gauge
symmetry so that it becomes a trivial gauge fixing to make the Einstein term
canonical in a general matter-Yang-Mills-supergravity coupled system.Comment: 38 pages, no figures, LaTeX, version to appear in PTP
104(2000),835-86
Off-shell d=5 Supergravity coupled to Matter-Yang-Mills System
We present an off-shell formulation of matter-Yang-Mills system coupled to
supergravity in five dimensional space-time. We give an invariant action for
the general system of vector multiplets and hypermultiplets coupled to
supergravity as well as the supersymmetry transformation rules. All the
auxiliary fields are kept un-eliminated so that the supersymmetry
transformation rules remain unchanged even when the action is changed.Comment: 36 pages, no figures, LaTeX, version to appear in PTP
105(2001),323-35
Detection of an X-Ray Hot Region in the Virgo Cluster of Galaxies with ASCA
Based on mapping observations with ASCA, an unusual hot region with a spatial
extent of 1 square degree was discovered between M87 and M49 at a center
coordinate of R. A. = 12h 27m 36s and Dec. = (J2000). The X-ray
emission from the region has a 2-10 keV flux of ergs
s cm and a temperature of keV, which is
significantly higher than that in the surrounding medium of keV. The
internal thermal energy in the hot region is estimated to be ergs with a gas density of cm. A power-law
spectrum with a photon index is also allowed by the data. The hot
region suggests there is an energy input due to a shock which is probably
caused by the motion of the gas associated with M49, infalling toward the M87
cluster with a velocity km s.Comment: 12 pages, 3 figures, accepted to ApJ
XMM-Newton Observation of IC 310 in the Outer Region of the Perseus Cluster of Galaxies
We present results from an XMM-Newton observation of the head-tail radio
galaxy IC 310 located in the southwest region of the Perseus cluster. The
spectrum is well-fitted by an absorbed power-law model with a photon index of
with no significant absorption excess. The X-ray image shows a
point-like emission at IC 310 without any signs of a structure correlated with
the radio halo tail. The temperature of the intracluster medium surrounding IC
310 declines as a function of distance from the cluster center, from keV in the northeast corner of the field of view to about 3 keV in the
southwest region. Although we do not find any sharp edges in the surface
brightness profile, a brightness excess over a smooth model by about
20% is seen. The temperature also rises by about 10% in the same region. This
indicates that the IC 310 region is a subcluster probably infalling into the
Perseus cluster, and the gas in front of IC 310 towards the Perseus cluster is
likely to be compressed by the large-scale motion, which supports the view that
the IC 310 system is undergoing a merger.Comment: 7 pages, 8 figures (including color), accepted for publication in
PAS
Temperature Variation in the Cluster of Galaxies Abell 115 Studied with ASCA
Abell 115 exhibits two distinct peaks in the surface brightness distribution.
ASCA observation shows a significant temperature variation in this cluster,
confirmed by a hardness ratio analysis and spectral fits. A linking region
between main and sub clusters shows a high temperature compared with other
regions. Two possibilities are examined as the cause of the temperature
variation: cooling flows in the main cluster and a shock heating due to the
collision of the subcluster into the main system. Spectral fits with cooling
flow models to the main-cluster data show a mass-deposition rate less than 419
solar-mass/yr. Temperatures in the main cluster, the linking region, and the
subcluster are estimated by correcting for the effects of X-ray telescope
response as 4.9 (+0.7/-0.6), 11 (+12/-4), and 5.2 (+1.4/-1.0) keV,
respectively. The high temperature in the linking region implies that Abell 115
is indeed a merger system, with possible contribution from cooling flows on the
temperature structure.Comment: 23 pages, including 7 Postscript figures, accepted for publication in
Ap
Monopole-vortex complex in a theta vacuum
We discuss aspects of the monopole-vortex complex soliton arising in a
hierarchically broken gauge system, G to H to 1, in a theta vacuum of the
underlying G theory. Here we focus our attention mainly on the simplest such
system with G=SU(2) and H=U(1). A consistent picture of the effect of the theta
parameter is found both in a macroscopic, dual picture and in a microscopic
description of the monopole-vortex complex soliton.Comment: 18 pages 3 figure
New Josephson Plasma Modes in Underdoped YBa2Cu3O6.6 Induced by Parallel Magnetic Field
The c-axis reflectivity spectrum of underdoped YBa2Cu3O6.6 (YBCO) is measured
below Tc=59K in parallel magnetic fields H//CuO2 up to 7T. Upon application of
a parallel field, a new peak appears at finite frequency in the optical
conductivity at the expense of suppression of c-axis condensate weight. We
conclude that the dramatic change originates from different Josephson coupling
strengths between bilayers with and without Josephson vortices. We find that
the 400cm^-1 broad conductivity peak in YBCO gains the spectral weight under
parallel magnetic field; this indicates that the condensate weight at \omega =0
is distributed to the intra-bilayer mode as well as to the new optical
Josephson mode.Comment: 4 pages, 3 figure
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