Galaxy imaging surveys as spin-sensitive detector for cosmological colliders
Cosmology and Nongalactic Astrophysics2021-03-22v2High Energy Astrophysical PhenomenaGeneral Relativity and Quantum CosmologyHigh Energy Physics - PhenomenologyHigh Energy Physics - Theory
Galaxy imaging surveys provide us with information on both the galaxy distribution and their shapes. In this paper, we systematically investigate the sensitivity of galaxy shapes to new physics in the initial conditions. For this purpose, we decompose the galaxy shape function into spin components, and compute the contributions to each spin component from both intrinsic alignment and weak lensing. We then consider the angular-dependent primordial non-Gaussianity, which is generated by a non-zero integer spin particle when active during inflation, and show that a galaxy imaging survey essentially functions as a spin-sensitive detector of such particles in the early universe. We also perform a forecast of the PNG generated from a higher spin particle, considering a Rubin Observatory LSST-like galaxy survey.
@article{arxiv.2009.05517,
title = {Galaxy imaging surveys as spin-sensitive detector for cosmological colliders},
author = {Kazuhiro Kogai and Kazuyuki Akitsu and Fabian Schmidt and Yuko Urakawa},
journal= {arXiv preprint arXiv:2009.05517},
year = {2021}
}