Implications of baryon-dark matter interaction on IGM temperature and tSZ effect with magnetic field

Abstract

We show that the combined effect of cosmic magnetic field and a possible non-standard interaction between baryons and dark matter has interesting consequences on the thermal Sunyaev$-$Zel${}^{\prime }$dovich (tSZ) effect depending on the temperature and the ionization state of the intergalactic medium. The drag force between the baryons and dark matter due to the relative velocity between them, and their temperature difference results in heat transfer between these two species. At the same time the ambipolar diffusion and the decaying magnetic turbulence tends to heat up the baryons. This interplay of these two processes give rise to different evolution histories of the thermal and ionization state of the universe and hence influences the CMB spectrum at small scales through the tSZ effect. In this work, we have computed the evolution of the temperature, ionization fraction and the y-parameter of the CMB for different strengths of the magnetic field and the interaction cross-section. We note that an interaction cross-section of ${\sigma }_0=10^{-42}$ m${}^2$ (with a magnetic field strength of $3.0$ nG) reduces the y-parameter by an order of magnitude as compared to the case with similar strength of magnetic field but where there is no such interaction between the baryons and dark matter.

13 pages, 11 figures (comments are welcome)

References in corpus (14)

• Strong magnetic fields in normal galaxies at high redshifts
• Lower limit on the strength and filling factor of extragalactic magnetic fields
• Turning off the Lights: How Dark is Dark Matter?
• Resonant Dark Forces and Small Scale Structure
• A Global Probe of Cosmic Magnetic Fields to High Redshifts
• Magnetic Field Seeding by Galactic Winds
• The Effects of Dark Matter-Baryon Scattering on Redshifted 21 cm Signals
• New bounds on millicharged particles from cosmology
• Fluctuation dynamos and their Faraday rotation signatures
• Three-fluid plasmas in star formation II. Momentum transfer rate coefficients
• Reionization - A probe for the stellar population and the physics of the early universe
• Three-fluid plasmas in star formation I. Magneto-hydrodynamic equations
• Probing Primordial Magnetic Fields with the 21cm Fluctuations
• Constraints on Dark Matter-Baryon Scattering from the Temperature Evolution of the Intergalactic Medium