MG15 - Talk detail

Back to previous page

 Participant

Institution

Session

Accepted

Order

Time

Talk

Title

Abstract

Cosmic Microwave Background (CMB) is a unique probe to the Universe which carries the signatures of cosmic secrets from a vast range of redshifts. Along with the spatial fluctuations in the blackbody part of CMB, the spectral distortions in CMB blackbody also carries information about several cosmological and astrophysical phenomena. I will discuss one of such promising phenomena which can arise from the conversion of the CMB photons to axions in the presence of an external magnetic field. These induce a new kind of spectral distortions arising from the resonant and non-resonant conversion happening in the galaxy clusters, voids and also in the Milky Way. In the presence of Milky Way magnetic field, this phenomenon produces a unique anisotropic completely polarized spectral distortion in the CMB blackbody from the resonant conversion and partially or completely unpolarized spectral distortions from the non-resonant conversion. These new kinds of spectral distortion open up a window to probe axions over a wide mass range, which also encompasses the viable mass range for axions to be the dark matter. With the future CMB missions, a wide range of the axions or the axion-like particles will be explored with an unprecedented accuracy, which will be capable to answer several questions in fundamental physics.

Pdf file

Session

Accepted

Order

Time

Talk

Title

Abstract

The observations of the energy spectrum and spatial anisotropies of the cosmic microwave background (CMB) radiation has spearheaded the transition into an era of precision cosmology. The previous CMB space missions have explored the temperature anisotropies and part of the polarization anisotropies with high accuracy and have allowed us to make an accurate determination of the cosmological parameters. However, most of the polarisation information and an almost untouched spectral information remains to be mapped out with a more capable mission with high-value returns for cosmology and high energy physics. I will present a case for an India led next-generation CMB space mission capable to map the sky with both imager and spectrometer over a wide frequency range. This mission carries the capability to make high-resolution B-mode maps and also to probe CMB spectral distortions with an unprecedented accuracy. Along with multiple high science dividends in cosmology, this mission will also provide a golden dataset to study several astrophysical aspects of our galaxy.

Pdf file

Back to previous page