Search Publications
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…
Astrometric search for ultralight dark matter
Kim, Hyungjin
Precision astrometry offers a way to probe new physics. By measuring the angular position of light sources at unprecedented precision, astrometry could probe minuscule fluctuations of underlying spacetime. This work explores the possibility of probing ultralight dark matter candidates using precision astrometry. Through the coherent and stochastic…
Refining Galactic primordial black hole evaporation constraints
Balaji, Shyam; Koechler, Jordan; Luque, Pedro De la Torre
We revisit the role of primordial black holes (PBHs) as potential dark matter (DM) candidates, particularly focusing on light asteroid-mass PBHs. These PBHs are expected to emit particles through Hawking evaporation that can generate cosmic rays (CRs), eventually producing other secondary radiations through their propagation in the Milky Way, in a…
Novel bounds on decaying axionlike particle dark matter from the cosmic background
Horns, Dieter; Porras-Bedmar, Sara; Meyer, Manuel
The cosmic background (CB) is defined as the isotropic diffuse radiation field with extragalactic origin found across the electromagnetic spectrum. Different astrophysical sources dominate the CB emission at different energies, such as stars in the optical or active galactic nuclei in x rays. Assuming that dark matter consists of axions or axionli…
Resonant conversion of gravitational waves in neutron star magnetospheres
McDonald, Jamie I.; Ellis, Sebastian A. R.
High-frequency gravitational waves are the subject of rapidly growing interest in the theoretical and experimental community. In this work we calculate the resonant conversion of gravitational waves into photons in the magnetospheres of neutron stars via the inverse Gertsenshtein mechanism. The resonance occurs in regions where the vacuum birefrin…
Galactic structure from binary pulsar accelerations: Beyond smooth models
Chang, Philip; Widrow, Lawrence M.; Lam, Michael T. +3 more
We measure the line-of-sight accelerations of 26 binary pulsars due to the Milky Way's gravitational potential, and produce a three-dimensional map of the acceleration field of the Galaxy. Acceleration measurements directly give us the change in the line-of-sight velocity at present day, without requiring any assumptions inherent to kinematic mode…