Cosmological Particle Production and Pairwise Hotspots on the CMB. (arXiv:2107.09061v1 [hep-ph])

<a href="http://arxiv.org/find/hep-ph/1/au:+Kim_J/0/1/0/all/0/1">Jeong Han Kim</a>, <a href="http://arxiv.org/find/hep-ph/1/au:+Kumar_S/0/1/0/all/0/1">Soubhik Kumar</a>, <a href="http://arxiv.org/find/hep-ph/1/au:+Martin_A/0/1/0/all/0/1">Adam Martin</a>, <a href="http://arxiv.org/find/hep-ph/1/au:+Tsai_Y/0/1/0/all/0/1">Yuhsin Tsai</a>

Heavy particles with masses much bigger than the inflationary Hubble scale

$H_*$, can get non-adiabatically pair produced during inflation through their

couplings to the inflaton. If such couplings give rise to time-dependent masses

for the heavy particles, then following their production, the heavy particles

modify the curvature perturbation around their locations in a time-dependent

and scale non-invariant manner. This results into a non-trivial spatial profile

of the curvature perturbation that is preserved on superhorizon scales and

eventually generates localized hot or cold spots on the CMB. We explore this

phenomenon by studying the inflationary production of heavy scalars and derive

the final temperature profile of the spots on the CMB by taking into account

the subhorizon evolution, focusing in particular on the parameter space where

pairwise hot spots (PHS) arise. When the heavy scalar has an $mathcal{O}(1)$

coupling to the inflaton, we show that for an idealized situation where the

dominant background to the PHS signal comes from the standard CMB fluctuations

themselves, a simple position space search based on applying a temperature cut,

can be sensitive to heavy particle masses $M_0/H_*simmathcal{O}(100)$. The

corresponding PHS signal also modifies the CMB power spectra and bispectra,

although the corrections are below (outside) the sensitivity of current

measurements (searches).

Heavy particles with masses much bigger than the inflationary Hubble scale

$H_*$, can get non-adiabatically pair produced during inflation through their

couplings to the inflaton. If such couplings give rise to time-dependent masses

for the heavy particles, then following their production, the heavy particles

modify the curvature perturbation around their locations in a time-dependent

and scale non-invariant manner. This results into a non-trivial spatial profile

of the curvature perturbation that is preserved on superhorizon scales and

eventually generates localized hot or cold spots on the CMB. We explore this

phenomenon by studying the inflationary production of heavy scalars and derive

the final temperature profile of the spots on the CMB by taking into account

the subhorizon evolution, focusing in particular on the parameter space where

pairwise hot spots (PHS) arise. When the heavy scalar has an $mathcal{O}(1)$

coupling to the inflaton, we show that for an idealized situation where the

dominant background to the PHS signal comes from the standard CMB fluctuations

themselves, a simple position space search based on applying a temperature cut,

can be sensitive to heavy particle masses $M_0/H_*simmathcal{O}(100)$. The

corresponding PHS signal also modifies the CMB power spectra and bispectra,

although the corrections are below (outside) the sensitivity of current

measurements (searches).

http://arxiv.org/icons/sfx.gif