4 papers
First Search for Kaluza-Klein Gravitons and Radion Using Planck Data
Alexander P. Cassem, Soubhik Kumar
Heavy moduli and Kaluza-Klein (KK) gravitons from extra dimensions may evade terrestrial probes but can be produced during inflation, generating primordial non-Gaussianity (NG) thr…
Cosmological and Astrophysical Constraints on Late First-Order Phase Transitions
Kylar Greene, Daven Wei Ren Ho, Soubhik Kumar +1
First-order cosmological phase transitions (PT) can take place in a dark sector at relatively late times between the big-bang nucleosynthesis and recombination epochs. Because bubb…
Warped Dimensions at the Cosmological Collider
Soubhik Kumar, Michael Nee
Extra dimensions are present in many beyond the Standard Model scenarios, most notably in string theory. However, direct signatures of extra dimensions are difficult to observe in…
Cosmological Constraints on Secluded Dark Radiation
Jae Hyeok Chang, Peizhi Du, Subhajit Ghosh +1
Dark radiation (DR) is ubiquitous in physics beyond the Standard Model (SM), and its interactions with the SM and dark matter (DM) lead to a variety of interesting effects on cosmo…