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In this lecture we look at:
1) Neutron stars in x-ray binaries
2) Mass-radius relationship
3) Strange star candidates
4) Quark deconfinement at T=0
5) Astrophysical signals of quark matter
Alfen radius
RXJ 1856.5-3754
Drake et al. point out that this NS may in fact be a quark star
(astro-ph/0204159) because of its small radius, which they
argue is in the range between
R' = 3.8 and 8.2 km!!
ÄÄ
Nasa press release of 10 April 2002:
"Cosmic x-rays reveal evidence for new form of
matter"
WWW.msfc.nasa.gov/news
Star's x-ray spectrum
is well represented by
a black body with a
temperature of
T'=7x105 K (X60 eV)
The observed x-ray flux
and temperature
correspond to a stellar
radius of
R'= R (1-2M/R)-1/2
Y f (D/120 pc) km
Drake et al.:
R'=3.8 to 8.2 km
Rotationally deformed, rotating neutron star
Pulsar 3C58
" A 65 ms pulsar (J0205+6449) was discovered by Murray et al.
(to appear in the ApJ, 2002).
" This pulsar is at the center of 3C58, a young Crab-like supernova
remnant (SN 1181).
" Thus 3C58 is somewhat younger than Crab.
" The pulsar's surface temperature is 1.12x106 K (Slane, Helfand, Murray,
astro-ph/0204151, to appear in the ApJ)
Nasa press release of 10 April 2002:
"Cosmic x-rays reveal evidence for new form of matter"
www.msfc.nasa.gov/news