Journal Article

Intergalactic medium heating by dark matter

E. Ripamonti, M. Mapelli and A. Ferrara

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 374, issue 3, pages 1067-1077
Published in print January 2007 | ISSN: 0035-8711
Published online December 2006 | e-ISSN: 1365-2966 | DOI:
Intergalactic medium heating by dark matter

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics


Show Summary Details


We derive the evolution of the energy deposition in the intergalactic medium (IGM) by dark matter (DM) decays/annihilations for both sterile neutrinos and light dark matter (LDM) particles. At z > 200 sterile neutrinos transfer a fraction fabs∼ 0.5 of their rest mass energy into the IGM; at lower redshifts this fraction becomes ≲0.3 depending on the particle mass. The LDM particles can decay or annihilate. In both the cases fabs∼ 0.4–0.9 at high (>300) redshift, dropping to ≈0.1 below z= 100. These results indicate that the impact of DM decays/annihilations on the IGM thermal and ionization history is less important than previously thought. We find that sterile neutrinos (LDM) decays are able to increase the IGM temperature by z= 5 at most up to 4 K (100 K), about 50–200 times less than predicted by estimates based on the assumption of complete energy transfer to the gas.

Keywords: neutrinos; ISM: evolution; dark matter

Journal Article.  7786 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. subscribe or login to access all content.