Download www.if.ufrgs.br

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

Astronomical spectroscopy wikipedia, lookup

P-nuclei wikipedia, lookup

X-ray astronomy detector wikipedia, lookup

Aquarius (constellation) wikipedia, lookup

Ursa Minor wikipedia, lookup

Corvus (constellation) wikipedia, lookup

Perseus (constellation) wikipedia, lookup

Cygnus (constellation) wikipedia, lookup

Timeline of astronomy wikipedia, lookup

Observational astronomy wikipedia, lookup

Lyra wikipedia, lookup

Extraterrestrial life wikipedia, lookup

Space Interferometry Mission wikipedia, lookup

XMM-Newton wikipedia, lookup

Structure formation wikipedia, lookup

Stellar evolution wikipedia, lookup

Star formation wikipedia, lookup

Type II supernova wikipedia, lookup

Dyson sphere wikipedia, lookup

Star of Bethlehem wikipedia, lookup

History of supernova observation wikipedia, lookup

Crab Nebula wikipedia, lookup

SN 1054 wikipedia, lookup

X-ray astronomy satellite wikipedia, lookup

History of X-ray astronomy wikipedia, lookup

X-ray astronomy wikipedia, lookup

Drake equation wikipedia, lookup

Transcript
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