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Description
This table contains the results of a Chandra survey of low-mass X-ray binaries (LMXBs) in 24 early-type galaxies. Correcting for detection incompleteness, the X-ray luminosity function (XLF) of each galaxy is consistent with a power law with negative logarithmic differential slope, Beta, ~ 2.0. However, Beta strongly correlates with incompleteness, indicating the XLF flattens at low X-ray luminosity (L<sub>X</sub>). The composite XLF is well fitted by a power law with a break at (2.21 [+0.65,-0.56]) x 10<sup>38</sup> erg s<sup>-1</sup> and Beta = 1.40 [+0.10,-0.13] and = 2.84 [+0.39,-0.30] below and above it, respectively. The break is close to the Eddington limit for a 1.4 solar-mass neutron star, but the XLF shape rules out its representing the division between neutron star and black hole systems. Although the XLFs are similar, the authors find evidence of some variation between galaxies. The high-L<sub>X</sub> XLF slope does not correlate with age, but may correlate with [Alpha/Fe]. Considering only LMXBs with L<sub>X</sub> > 10<sup>37</sup> erg s<sup>-1</sup>, matching the LMXBs with globular clusters (GCs) identified in HST observations of 19 of the galaxies, the authors find the probability a GC hosts an LMXB is proportional to L<sub>GC</sub><sup>Alpha</sup> Z<sub>Fe</sub><sup>Gamma</sup> where Alpha = 1.01 +/- 0.19 and Gamma = 0.33 +/- 0.11. Correcting for GC luminosity and color effects, and detection incompleteness, they find no evidence that the fraction of LMXBs with L<sub>X</sub> > 10<sup>37</sup> erg s<sup>-1</sup> in GCs (40%), or the fraction of GCs hosting LMXBs (~ 6.5%) varies between galaxies. The spatial distribution of LMXBs resembles that of GCs, and the specific frequency of LMXBs is proportional to the GC specific luminosity, consistent with the hypothesis that all LMXBs form in GCs. If the LMXB lifetime is Tau<sub>L</sub> and the duty cycle is F<sub>d</sub>, their results imply ~ 1.5(Tau<sub>L</sub>/10<sup>8</sup> yr)<sup>-1</sup> F<sub>d</sub><sup>-1</sup> LMXBs are formed per gigayear per GC, and they place an upper limit of one active LMXB in the field per 3.4 x 10<sup>9</sup> solar luminosities of V-band luminosity. This table contains 1194 X-ray point sources that were detected within the B-band 25th magnitude ellipse D<sub>25</sub> (as listed in the de Vaucouleurs et al. Catalog of Bright Galaxies) of 24 early-type galaxies observed by Chandra (listed in Table 1 of the reference paper). The D<sub>25</sub> restriction should mitigate against contamination by background AGNs. This table was created by the HEASARC in February 2009 based on the electronic versions of Table 6 from the paper which was obtained from the Astrophysical Journal web site. This is a service provided by NASA HEASARC .
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