TY - JOUR
T1 - The MAVERIC survey
T2 - Chandra/ACIS catalog of faint X-ray sources in 38 galactic globular clusters
AU - Bahramian, Arash
AU - Strader, Jay
AU - Miller-Jones, James C.A.
AU - Chomiuk, Laura
AU - Heinke, Craig O.
AU - Maccarone, Thomas J.
AU - Pooley, David
AU - Shishkovsky, Laura
AU - Tudor, Vlad
AU - Zhao, Yue
AU - Li, Kwan Lok
AU - Sivakoff, Gregory R.
AU - Tremou, Evangelia
AU - Buchner, Johannes
N1 - Publisher Copyright:
© 2020. The Author(s). Published by the American Astronomical Society.
PY - 2020/9/20
Y1 - 2020/9/20
N2 - Globular clusters host a variety of lower-luminosity (LX < 1035 erg s−1) X-ray sources, including accreting neutron stars (NSs) and black holes (BHs), millisecond pulsars (MSPs), cataclysmic variables, and chromospherically active binaries. In this paper, we provide a comprehensive catalog of more than 1100 X-ray sources in 38 Galactic globular clusters (GCs) observed by the Chandra X-ray Observatory's Chandra/ACIS detector. The targets are selected to complement the MAVERIC survey's deep radio continuum maps of Galactic GCs. We perform photometry and spectral analysis for each source, determine a best-fit model, and assess the possibility of it being a foreground or background source based on its spectral properties and location in the cluster. We also provide basic assessments of variability. We discuss the distribution of X-ray binaries in GCs and their X-ray luminosity function, and we carefully analyze systems with LX > 1033 erg s−1. Among these moderately bright systems, we discover a new source in NGC 6539 that may be a candidate accreting stellar-mass BH or a transitional MSP. We show that quiescent NS low-mass X-ray binaries in GCs may spend ∼2% of their lifetimes as transitional MSPs in their active (LX > 1033 erg s−1) state. Finally, we identify a substantial underabundance of bright (LX > 1033 erg s−1) intermediate polars in GCs compared to the Galactic field, in contrast with the literature of the past two decades.
AB - Globular clusters host a variety of lower-luminosity (LX < 1035 erg s−1) X-ray sources, including accreting neutron stars (NSs) and black holes (BHs), millisecond pulsars (MSPs), cataclysmic variables, and chromospherically active binaries. In this paper, we provide a comprehensive catalog of more than 1100 X-ray sources in 38 Galactic globular clusters (GCs) observed by the Chandra X-ray Observatory's Chandra/ACIS detector. The targets are selected to complement the MAVERIC survey's deep radio continuum maps of Galactic GCs. We perform photometry and spectral analysis for each source, determine a best-fit model, and assess the possibility of it being a foreground or background source based on its spectral properties and location in the cluster. We also provide basic assessments of variability. We discuss the distribution of X-ray binaries in GCs and their X-ray luminosity function, and we carefully analyze systems with LX > 1033 erg s−1. Among these moderately bright systems, we discover a new source in NGC 6539 that may be a candidate accreting stellar-mass BH or a transitional MSP. We show that quiescent NS low-mass X-ray binaries in GCs may spend ∼2% of their lifetimes as transitional MSPs in their active (LX > 1033 erg s−1) state. Finally, we identify a substantial underabundance of bright (LX > 1033 erg s−1) intermediate polars in GCs compared to the Galactic field, in contrast with the literature of the past two decades.
KW - Astrophysical black holes (98)
KW - Celestial objects catalogs (212)
KW - Globular star clusters (656)
KW - Low-mass x-ray binary stars (939)
KW - Neutron stars (1108)
KW - Stellar accretion disks (1579)
UR - http://www.scopus.com/inward/record.url?scp=85092631442&partnerID=8YFLogxK
U2 - 10.3847/1538-4357/aba51d
DO - 10.3847/1538-4357/aba51d
M3 - Review article
AN - SCOPUS:85092631442
SN - 0004-637X
VL - 901
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
M1 - 57
ER -