Journal Article

Extragalactic constraints on the initial mass function

Stephen M. Wilkins, Andrew M. Hopkins, Neil Trentham and Rita Tojeiro

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 391, issue 1, pages 363-368
Published in print November 2008 | ISSN: 0035-8711
Published online November 2008 | e-ISSN: 1365-2966 | DOI:
Extragalactic constraints on the initial mass function

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics


Show Summary Details


The local stellar mass density is observed to be significantly lower than the value obtained from integrating the cosmic star formation history (SFH), assuming that all the stars formed with a Salpeter initial mass function (IMF). Even other favoured IMFs, more successful in reconciling the observed z= 0 stellar mass density with that inferred from the SFH, have difficulties in reproducing the stellar mass density observed at higher redshift. In this study, we investigate to what extent this discrepancy can be alleviated for any universal power-law IMF. We find that an IMF with a high-mass slope shallower (2.15) than the Salpeter slope (2.35) reconciles the observed stellar mass density with the cosmic SFH, but only at low redshifts. At higher redshifts z > 0.5, we find that the observed stellar mass densities are systematically lower than predicted from the cosmic SFH, for any universal power-law IMF.

Keywords: galaxies: stellar content; cosmology: observations

Journal Article.  4177 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.