TY - JOUR
T1 - A deeper look at the X-ray point source population of NGC 4472
AU - Joseph, T. D.
AU - Maccarone, T. J.
AU - Kraft, R. P.
AU - Sivakoff, G. R.
N1 - Funding Information:
TDJ acknowledges support from the Stobie-SALT studentship, funded jointly by the National Research Foundation of SouthAfrica, the British Council and the University of Southampton. TDJ acknowledges the South Africa National Research Foundation Square Kilometre Array Research Fellowship. This material is based upon work supported by the National Aeronautics and Space Administration under Grants No. NAS8-03060 and GO1-12160X. This research has made use of data obtained from the Chandra Data Archive and software provided by the Chandra X-ray Center (CXC) in the application packages CIAO and CHIPS. TDJ would also like to thank Texas Tech University for its hospitality while this work was being finished and Mark Burke for his assistance.
Publisher Copyright:
© 2017 The Authors.
PY - 2017/10
Y1 - 2017/10
N2 - In this paper we discuss the X-ray point source population of NGC 4472, an elliptical galaxy in the Virgo cluster. We used recent deep Chandra data combined with archival Chandra data to obtain a 380 ks exposure time. We find 238 X-ray point sources within 3.7 arcmin of the galaxy centre, with a completeness flux, FX, 0.5-2 keV = 6.3 × 10-16 erg s-1 cm-2. Most of these sources are expected to be low-mass X-ray binaries. We finding that, using data from a single galaxy which is both complete and has a large number of objects (~100) below 1038 erg s-1, the X-ray luminosity function is well fitted with a single power-law model. By cross matching our X-ray data with both space based and ground based optical data for NGC 4472, we find that 80 of the 238 sources are in globular clusters. We compare the red and blue globular cluster subpopulations and find red clusters are nearly six times more likely to host an X-ray source than blue clusters. We show that there is evidence that these two subpopulations have significantly different X-ray luminosity distributions. Source catalogues for all X-ray point sources, as well as any corresponding optical data for globular cluster sources, are also presented here.
AB - In this paper we discuss the X-ray point source population of NGC 4472, an elliptical galaxy in the Virgo cluster. We used recent deep Chandra data combined with archival Chandra data to obtain a 380 ks exposure time. We find 238 X-ray point sources within 3.7 arcmin of the galaxy centre, with a completeness flux, FX, 0.5-2 keV = 6.3 × 10-16 erg s-1 cm-2. Most of these sources are expected to be low-mass X-ray binaries. We finding that, using data from a single galaxy which is both complete and has a large number of objects (~100) below 1038 erg s-1, the X-ray luminosity function is well fitted with a single power-law model. By cross matching our X-ray data with both space based and ground based optical data for NGC 4472, we find that 80 of the 238 sources are in globular clusters. We compare the red and blue globular cluster subpopulations and find red clusters are nearly six times more likely to host an X-ray source than blue clusters. We show that there is evidence that these two subpopulations have significantly different X-ray luminosity distributions. Source catalogues for all X-ray point sources, as well as any corresponding optical data for globular cluster sources, are also presented here.
KW - Stars: low mass
KW - X-rays: binaries
KW - X-rays: individual: NGC 4472
UR - http://www.scopus.com/inward/record.url?scp=85052536193&partnerID=8YFLogxK
U2 - 10.1093/MNRAS/STX1383
DO - 10.1093/MNRAS/STX1383
M3 - Article
AN - SCOPUS:85052536193
VL - 470
SP - 4133
EP - 4144
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 4
ER -