Search Publications
Standard siren measurement of the Hubble constant using GW170817 and the latest observations of the electromagnetic counterpart afterglow
Palmese, A.; Margutti, R.; Hajela, A. +3 more
We present a new constraint on the Hubble constant H0 using the latest measurements of the electromagnetic counterpart to the gravitational wave (GW) event GW170817. We use the latest optical, x-ray and radio observations of the afterglow up to ∼3.5 years after the GW detection, and properly take into account the impact of the host gala…
Multimessenger search for electrophilic feebly interacting particles from supernovae
Carenza, Pierluca; Balaji, Shyam; Luque, Pedro De la Torre
We study MeV-scale electrophilic feebly interacting particles (FIPs), that may be abundantly produced in supernova explosions, escape the star and decay into electrons and positrons. This exotic injection of leptons in the Milky Way leaves an imprint in both photon and cosmic ray fluxes. Specifically, positrons lose energy and annihilate almost at…
Robust constraints on feebly interacting particles using XMM-Newton
Carenza, Pierluca; Balaji, Shyam; Luque, Pedro De la Torre
During galactic supernova (SN) explosions, a large amount of feebly interacting particles (FIPs) may be produced. In this work we analyze electrophilic FIPs with masses in the MeV-range that escape from SN and decay into electron-positron pairs, causing an exotic leptonic injection. This contribution adds up to known components, leading to an unex…
New bounds on light millicharged particles from the tip of the red-giant branch
Vincent, Aaron C.; Schutz, Katelin; Fung, Audrey +3 more
Stellar energy loss is a sensitive probe of light, weakly coupled dark sectors, including ones containing millicharged particles (MCPs). The emission of MCPs can affect stellar evolution and therefore can alter the observed properties of stellar populations. In this work, we improve upon the accuracy of existing stellar limits on MCPs by self-cons…
High-redshift JWST massive galaxies and the initial clustering of supermassive primordial black holes
Piao, Yun-Song; Huang, Hai-Long; Jiang, Jun-Qian
In this paper, we show that the initial clustering of supermassive primordial black holes (SMPBHs) beyond a Poisson distribution can efficiently enhance the matter power spectrum, and thus the halo mass function. As a result, the population of initially clustered SMPBHs with
Platform and environment requirements of a satellite quantum test of the weak equivalence principle at the 10-17 level
Métris, Gilles; Struckmann, Christian; Corgier, Robin +6 more
The space-time explorer and quantum equivalence principle space test (STE-QUEST) recently proposed, aims at performing a precision test of the weak equivalence principle (WEP), a fundamental cornerstone of general relativity. Taking advantage of the ideal operation conditions for high-precision quantum sensing on board of a satellite, it aims to d…
Exploring reheated sub-40000 Kelvin neutron stars with JWST, ELT, and TMT
Raj, Nirmal; Shivanna, Prajwal; Rachh, Gaurav Niraj
Neutron stars cooling passively since their birth may be reheated in their late-stage evolution by a number of possible phenomena; rotochemical, vortex creep, crust cracking, magnetic field decay, or more exotic processes such as removal of neutrons from their Fermi seas (the nucleon Auger effect), baryon number-violating nucleon decay, and accret…
Searching for electromagnetic emission in an AGN from the gravitational wave binary black hole merger candidate S230922g
Valdes, Francisco; Andreoni, Igor; Graham, Matthew J. +18 more
We carried out long-term monitoring of the LIGO/Virgo/KAGRA binary black hole (BBH) merger candidate S230922g in search of electromagnetic emission from the interaction of the merger remnant with an embedding active galactic nuclei (AGN) accretion disk. Using a dataset primarily composed of wide-field imaging from the Dark Energy Camera and supple…
In-depth analysis of LISA Pathfinder performance results: Time evolution, noise projection, physical models, and implications for LISA
Mendes, L.; Russano, G.; Nofrarias, M. +78 more
We present an in-depth analysis of the LISA Pathfinder differential acceleration performance over the entire course of its science operations, spanning approximately 500 days. We find: (1) The evolution of the Brownian noise that dominates the acceleration amplitude spectral density (ASD), for frequencies f≳1 mHz, is consistent with the decaying p…
Nontensorial gravitational wave polarizations from the tensorial degrees of freedom: Linearized Lorentz-violating theory of gravity
Zhu, Zong-Hong; Hou, Shaoqi; Zhu, Tao +1 more
General relativity predicts the existence of only two tensorial gravitational wave polarizations, while a generic metric theory of gravity can possess up to four additional polarizations, including two vectors and two scalar ones. These vector/scalar polarizations are in general generated by the intrinsic new vector/scalar degrees of freedom of th…