Search Publications
Astrophysical constraints on decaying dark gravitons
Obied, Georges; Law-Smith, Jamie A. P.; Prabhu, Anirudh +1 more
In the dark dimension scenario, which predicts an extra dimension of micron scale, dark gravitons (KK modes) are a natural dark matter candidate. In this paper, we study observable features of this model. In particular, their decay to standard matter fields can distort the CMB and impact other astrophysical signals. Using this we place bounds on t…
Impact of the cosmic neutrino background on long-range force searches
Chauhan, Garv; Xu, Xun-Jie
Light bosons can mediate long-range forces. We show that light bosonic mediators interacting with a background medium, in particular, with the cosmic neutrino background (CνB), may induce medium-dependent masses which could effectively screen long-range forces from detection. This leads to profound implications for long-range force searches in e.g…
Spinning primordial black holes from first order phase transition
Banerjee, Indra Kumar; Dey, Ujjal Kumar
We conduct a novel study to obtain the initial spin of the primordial black holes created during a first-order phase transition due to delayed false vacuum decay. Remaining within the parameter space consistent with observational bounds, we express the abundance and the initial spin of the primordial black holes as functions of the phase transitio…
Light thermal dark matter beyond p-wave annihilation in minimal Higgs portal model
Wu, Lei; Chen, Yu-Tong; Matsumoto, Shigeki +2 more
This study explores a minimal renormalizable dark matter (DM) model, incorporating a sub-GeV Majorana DM and a singlet scalar particle ϕ. Using scalar and pseudo-scalar interactions (couplings cs and cp), we investigate implications for DM detection, considering s-wave, p-wave, and combined (s+p wave) contributions in DM anni…
Freezing-in cannibal dark sectors
Hryczuk, Andrzej; Cervantes, Esau
Self-Interacting Dark Matter models can successfully explain dark matter (DM) production through interactions confined within the dark sector. However, they often lack measurable experimental signals due to their secluded nature. Including a feeble interaction with the visible sector through a Higgs portal leads not only to potential detection ave…
Probing ultralight isospin-violating mediators at GW170817
Liu, Zuowei; Tang, Zi-Wei
Gravitational wave (GW) signals arising from binary neutron star mergers offer new, sensitive probes to ultralight mediators. Here we analyze the GW signals in the GW170817 event detected by the LIGO/Virgo collaboration to impose constraints on the ultralight isospin-violating mediator that has different couplings to protons and neutrons. Neutron …
Stepped partially acoustic dark matter, large scale structure, and the Hubble tension
Marques-Tavares, Gustavo; Buen-Abad, Manuel A.; Chacko, Zackaria +2 more
We propose a new interacting dark sector model, Stepped Partially Acoustic Dark Matter (SPartAcous), that can simultaneously address the two most important tensions in current cosmological data, the H0 and S8 problems. As in the Partially Acoustic Dark Matter (PAcDM) scenario, this model features a subcomponent of dark matter…
Precision cosmological constraints on atomic dark matter
Bansal, Saurabh; Barron, Jared; Curtin, David +1 more
Atomic dark matter is a simple but highly theoretically motivated possibility for an interacting dark sector that could constitute some or all of dark matter. We perform a comprehensive study of precision cosmological observables on minimal atomic dark matter, exploring for the first time the full parameter space of dark QED coupling and dark elec…
Updated constraints and future prospects on majoron dark matter
Akita, Kensuke; Niibo, Michiru
Majorons are (pseudo-)Nambu-Goldstone bosons associated with lepton number symmetry breaking due to the Majorana mass term of neutrinos introduced in the seesaw mechanism. They are good dark matter candidates since their lifetime is suppressed by the lepton number breaking scale. We update constraints and discuss future prospects on majoron dark m…
Probing minimal grand unification through gravitational waves, proton decay, and fermion masses
Saad, Shaikh
Motivated by the direct discovery of gravitational waves (GWs) from black holes and neutron stars, there is a growing interest in investigating GWs from other sources. Among them, GWs from cosmic strings are particularly fascinating since they naturally appear in a large class of grand unified theories (GUTs). Remarkably, a series of pulsar-timing…