A Chandra Study of the Dense Globular Cluster Terzan 5

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

18 pages, 8 figures, accepted to ApJ

Scientific paper

10.1086/375189

We report a Chandra ACIS-I observation of the dense globular cluster Terzan 5. The previously known transient low-mass x-ray binary (LMXB) EXO 1745-248 in the cluster entered a rare high state during our August 2000 observation, complicating the analysis. Nevertheless nine additional sources clearly associated with the cluster are also detected, ranging from L_X(0.5-2.5 keV)=5.6*10^{32} down to 8.6*10^{31} ergs/s. Their X-ray colors and luminosities, and spectral fitting, indicate that five of them are probably cataclysmic variables, and four are likely quiescent LMXBs containing neutron stars. We estimate the total number of sources between L_X(0.5-2.5 keV)=10^{32} and 10^{33} ergs/s as 11.4^{+4.7}_{-1.8} by the use of artificial point source tests, and note that the numbers of X-ray sources are similar to those detected in NGC 6440. The improved X-ray position allowed us to identify a plausible infrared counterpart to EXO 1745-248 on our 1998 Hubble Space Telescope NICMOS images. This blue star (F110W=18.48, F187W=17.30) lies within 0.2'' of the boresighted LMXB position. Simultaneous Rossi X-ray Timing Explorer (RXTE) spectra, combined with the Chandra spectrum, indicate that EXO 1745-248 is an ultracompact binary system, and show a strong broad 6.55 keV iron line and an 8 keV smeared reflection edge.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

A Chandra Study of the Dense Globular Cluster Terzan 5 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A Chandra Study of the Dense Globular Cluster Terzan 5, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Chandra Study of the Dense Globular Cluster Terzan 5 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-649291

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.