Impact of dark matter decays and annihilations on reionization
- Creators
- Mapelli, M.
-
Ferrara, A.
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Pierpaoli, E.
Abstract
One of the possible methods to distinguish among various dark matter (DM) candidates is to study the effects of DM decays. We consider four different DM candidates [light dark matter (LDM), gravitinos, neutralinos and sterile neutrinos], for each of them deriving the decaying/annihilation rate, the influence on reionization, matter temperature and cosmic microwave background (CMB) spectra. We find that LDM particles (1–10 MeV) and sterile neutrinos (2–8 keV) can be sources of partial early reionization (z ~< 100). However, their integrated contribution to Thomson optical depth is small (~< 0.01) with respect to the 3-yr WMAP results (τe = 0.09 ± 0.03). Finally, they can significantly affect the behaviour of matter temperature. On the contrary, effects of heavy DM candidates (gravitinos and neutralinos) on reionization and heating are minimal. All the considered DM particles have completely negligible effects on the CMB spectra.
Additional Information
© 2006 The Authors. Journal compilation © 2006 RAS. Accepted 2006 March 31. Received 2006 March 30; in original form 2006 February 16. We thank P. Ullio, A. Provenza, E. Ripamonti and K. Abazajian for useful discussions. We also acknowledge the Referee for his critical reading of the manuscript. EP is an ADVANCE fellow (NSF grant AST-0340648), also supported by NASA grant NAG5-11489.Attached Files
Published - MAPmnras06.pdf
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Additional details
- Eprint ID
- 10788
- Resolver ID
- CaltechAUTHORS:MAPmnras06
- NSF
- AST-0340648
- NASA
- NAG5-11489
- Created
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2008-06-10Created from EPrint's datestamp field
- Updated
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2021-11-08Created from EPrint's last_modified field
- Caltech groups
- TAPIR