72,714 research outputs found
Superburst: surface phenomenon of compact objects
We suggest that superbursts from some low mass X-ray binaries may be due to
breaking and re-formation of diquark pairs, on the surface of realistic strange
stars. Diquarks are expected to break up due to the explosion and shock of the
thermonuclear process. The subsequent production of copious diquark pairing may
produce sufficient energy to produce the superbursts.Comment: 4 pages; to appear in the Proceedings of COSPAR Colloquium "Spectra &
Timing of Compact X-ray Binaries," January 17-20, 2005, Mumbai, Indi
Evidence for strange stars from joint observation of harmonic absorption bands and of redshift
From recent reports on terrestrial heavy ion collision experiments it appears
that one may not obtain information about the existence of asymptotic freedom
(AF) and chiral symmetry restoration (CSR) for quarks of QCD at high density.
This information may still be obtained from compact stars - if they are made up
of strange quark matter. Very high gravitational redshift lines (GRL), seen
from some compact stars, seem to suggest high ratios of mass and radius (M/R)
for them. This is suggestive of strange stars (SS) and can in fact be fitted
very well with SQM equation of state deduced with built in AF and CSR. In some
other stars broad absorption bands appear at about ~ 0.3 keV and multiples
thereof, that may fit in very well with resonance with harmonic compressional
breathing mode frequencies of these SS. Emission at these frequencies are also
observed in six stars. If these two features of large GRL and BAB were observed
together in a single star, it would strengthen the possibility for the
existence of SS in nature and would vindicate the current dogma of AF and CSR
that we believe in QCD. Recently, in 4U 1700-24, both features appear to be
detected, which may well be interpreted as observation of SS - although the
group that analyzed the data did not observe this possibility. We predict that
if the shifted lines, that has been observed, are from neon with GRL shift z =
0.4 - then the compact object emitting it is a SS of mass 1.2 M_sun and radius
7 km. In addition the fit to the spectrum leaves a residual with broad dips at
0.35 keV and multiples thereof, as in 1E1207-5209 which is again suggestive of
SS.Comment: 5 pages, 4 figures, accepted for publication in the MNRA
An explicit predictor-corrector solver with applications to Burgers' equation
Forward Euler's explicit, finite-difference formula of extrapolation, is used as a predictor and a convex formula as a corrector to integrate differential equations numerically. An application has been made to Burger's equation
Geometric Quantization of the Hitchin System
This paper is about geometric quantization of the Hitchin system. We quantize
a Kahler form on the Hitchin moduli space (which is half the first Kahler form
defined by Hitchin) by considering the Quillen bundle as the prequantum line
bundle and modifying the Quillen metric using the Higgs field so that the
curvature is proportional to the Kahler form. We show that this Kahler form is
integral and the Quillen bundle descends as a prequantum line bundle on the
moduli space. It is holomorphic and hence one can take holomorphic square
integrable sections as the Hilbert space of quantization of the Hitchin moduli
space.Comment: to appear in IJGMM
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