Does the Reionization Model Influence the Constraints on Dark Matter Decay or Annihilation?

Abstract

If dark matter decay or annihilate, a large amount of energy and particles would be released into the cosmic plasma. Therefore, they could modify the thermal and ionization history of our universe, then leave footprints on the cosmic microwave background power spectra. In this paper, we take dark matter annihilation as an example and investigate whether different reionization models influence the constraints on dark matter annihilation. We consider the ionization history including both dark matter annihilation and star formation, then put constraints on DM annihilation. Combining the latest Planck data, BAO data, SNIa measurement, $Q_{\text{HII}}$ constraints from observations of quasars, as well as the star formation rate density from UV and IR data, the optical depth is $\tau =0.0571_{-0.0006}^{+0.0005}$ at 68$\%$C.L. and the upper limit of ${\epsilon }_0{f}_d$ reads $2.7765\times 10^{-24}$ at 95$\%$C.L.. By comparison, we also constrain dark matter annihilation in the instantaneous reionization model from the same data combination except the $Q_{\text{HII}}$ constraints and star formation rate density. We get $\tau =0.0559_{-0.0076}^{+0.0069}$ at 68$\%$C.L. and the upper limit of ${\epsilon }_0{f}_d$ is $2.8468\times 10^{-24}$ at 95$\%$C.L.. %, which is $2.5\%$ higher than the results in the previous model. This indicates various reionization models have little influence ($\lesssim 2.5\%$) on constraining parameters of dark matter decay or annihilation.

8 pages, 2 figures

References in corpus (13)

• Cosmic Star Formation History
• A direct empirical proof of the existence of dark matter
• The Clustering of the SDSS DR7 Main Galaxy Sample I: A 4 per cent Distance Measure at z=0.15
• Cosmic Reionization and Early Star-Forming Galaxies: A Joint Analysis of New Constraints from Planck and Hubble Space Telescope
• Precise Relic WIMP Abundance and its Impact on Searches for Dark Matter Annihilation
• Review of LHC Dark Matter Searches
• Line Emitting Galaxies Beyond a Redshift of 7: An Improved Method for Estimating the Evolving Neutrality of the Intergalactic Medium
• Dwarf galaxy annihilation and decay emission profiles for dark matter experiments
• Updated CMB constraints on Dark Matter annihilation cross-sections
• Impact of dark matter decays and annihilations on reionization
• The impacts of dark matter particle annihilation on recombination and the anisotropies of the cosmic microwave background
• Witnessing the reionization history using Cosmic Microwave Background observation from Planck
• Gaussian Process Reconstruction of Reionization History