X-ray selected starbursts in the GOODS-North

Details X-ray selected starbursts in the GOODS-North X-ray selected starbursts in the GOODS-North

2007-02-05

arxiv.org/abs/astro-ph/0702132v1

Mon.Not.Roy.Astron.Soc.377:203-214,2007

Astronomy and Astrophysics

Astrophysics

Accepted for publication in MNRAS

Scientific paper

10.1111/j.1365-2966.2007.11590.x

We investigate claims that recent deep X-ray surveys are detecting starbursts at cosmologically interesting redshifts (z=0-1). We combine X-ray data from the 2Ms CDF-North with multi-wavelength observations from GOODS to build the SEDs (UV, optical, IR) of X-ray sources in this field. These are fit with model templates providing an estimate of the total IR luminosity of each source. We then exploit the correlation between IR and X-ray luminosities for star-forming galaxies, established in the local Universe, to select sources that are dominated by star-formation. This approach is efficient in discriminating normal galaxies from AGN over a wide range of SFRs. The resulting sample consists of 45 X-ray selected star-forming systems at a median redshift z~0.5, the majority of which (60%) are LIRGs or ULIRGs. This sample is least affected by incompleteness and AGN contamination and is well suited for cosmological studies. We quantify the X-ray evolution of these sources by constructing their differential, dN/dS, and comparing them with evolving luminosity function models. The results are consistent with luminosity evolution of the form (1+z)^{p} with p~2.4. This is similar to the evolution rate of star-forming galaxies selected at other wavelengths, suggesting that the deep X-ray surveys, are indeed finding the starburst galaxy population that drives the rapid evolution of the global SFR density in the range z~0-1. Our analysis also reveals a separate population of IR-faint X-ray sources. These include old galaxies but also systems that are X-ray luminous for their stellar mass compared to local E/S0. We argue that these may be post-starbursts that will, over time, become fainter at X-rays and will eventually evolve into early-type systems (e.g. E/S0).

Affiliated with

Also associated with

No associations

Rating

X-ray selected starbursts in the GOODS-North 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 X-ray selected starbursts in the GOODS-North, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and X-ray selected starbursts in the GOODS-North will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-426511