The X-ray Luminosity Function of "The Antennae" Galaxies (NGC4038/39) and the Nature of Ultra-Luminous X-ray Sources

Details The X-ray Luminosity Function of "The Antennae" Galaxies (NGC4038/39) and the Nature of Ultra-Luminous X-ray Sources The X-ray Luminosity Function of "The Antennae" Galaxies (NGC4038/39) and the Nature of Ultra-Luminous X-ray Sources

2002-03-12

arxiv.org/abs/astro-ph/0203176v1

Astronomy and Astrophysics

Astrophysics

15 pages, submitted to ApJ

Scientific paper

We derive the X-ray luminosity function (XLF) of the X-ray source population detected in the Chandra observation of NGC4038/39 (the Antennae). We explicitly include photon counting and spectral parameter uncertainties in our calculations. The cumulative XLF is well represented by a flat power law ($\alpha=-0.47$), similar to those describing the XLFs of other star-forming systems (e.g. M82, the disk of M81), but different from those of early type galaxies. This result associates the X-ray source population in the Antennae with young High Mass X-ray Binaries. In comparison with less actively star-forming galaxies, the XLF of the Antennae has a highly significant excess of sources with luminosities above 10^{39} erg\s (Ultra Luminous Sources; ULXs). We discuss the nature of these sources, based on the XLF and on their general spectral properties, as well as their optical counterparts discussed in Paper III. We conclude that the majority of the ULXs cannot be intermediate mass black-holes (M > 10-1000 \msun) binaries, unless they are linked to the remnants of massive Population III stars (the Madau & Rees model). Instead, their spatial and multiwavelength properties can be well explained by beamed emission as a consequence of supercritical accretion. Binaries with a neutron star or moderate mass black-hole (up to 20\msun), and B2 to A type star companions would be consistent with our data. In the beaming scenario, the XLF should exibit caracteristic breaks that will be visible in future deeper observations of the Antennae.

Affiliated with

Also associated with

No associations

Rating

The X-ray Luminosity Function of "The Antennae" Galaxies (NGC4038/39) and the Nature of Ultra-Luminous X-ray Sources 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 The X-ray Luminosity Function of "The Antennae" Galaxies (NGC4038/39) and the Nature of Ultra-Luminous X-ray Sources, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The X-ray Luminosity Function of "The Antennae" Galaxies (NGC4038/39) and the Nature of Ultra-Luminous X-ray Sources will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-263280