On the Evolutionary History of Stars and their Fossil Mass and Light

Details On the Evolutionary History of Stars and their Fossil Mass and Light On the Evolutionary History of Stars and their Fossil Mass and Light

2006-04-26

arxiv.org/abs/astro-ph/0604534v1

Mon.Not.Roy.Astron.Soc.379:985-1002,2007

Astronomy and Astrophysics

Astrophysics

21 pages, 7 figures, 3 tables; submitted to Monthly Notices

Scientific paper

10.1111/j.1365-2966.2007.11522.x

The total extragalactic background radiation can be an important test of the global star formation history (SFH). Using direct observational estimates of the SFH, along with standard assumptions about the initial mass function (IMF), we calculate the total extragalactic background radiation and the observed stellar density today. We show that plausible SFHs allow a significant range in each quantity, but that their ratio is very tightly constrained. Current estimates of the stellar mass and extragalactic background are difficult to reconcile, as long as the IMF is fixed to the Salpeter slope above 1 Msun. The joint confidence interval of these two quantities only agrees with that determined from the allowed range of SFH fits at the 3-sigma level, and for our best-fit values the discrepancy is about a factor of two. Alternative energy sources that contribute to the background, such as active galactic nuclei (AGN), Population III stars, or decaying particles, appear unlikely to resolve the discrepancy. However, changes to the IMF allow plausible solutions to the background problem. The simplest is an average IMF with an increased contribution from stars around 1.5--4 Msun. A ``paunchy'' IMF of this sort could emerge as a global average if low mass star formation is suppressed in galaxies experiencing rapid starbursts. Such an IMF is consistent with observations of star-forming regions, and would help to reconcile the fossil record of star formation with the directly observed SFH.

Affiliated with

Also associated with

No associations

Rating

On the Evolutionary History of Stars and their Fossil Mass and Light 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 On the Evolutionary History of Stars and their Fossil Mass and Light, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the Evolutionary History of Stars and their Fossil Mass and Light will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-504908