Search Publications
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…
Pulsar-based map of galactic acceleration
Moran, Abigail; Mingarelli, Chiara M. F.; Van Tilburg, Ken +1 more
Binary pulsars can be used to probe Galactic potential gradients through calculating their line-of-sight accelerations. We present the first data release of direct line-of-sight acceleration measurements for 29 binary pulsars. We validate these data with a local acceleration model, and compare our results to those from earlier works. We find evide…
Constraining the stochastic gravitational wave background using the future lunar seismometers
Zhang, Fan; Chen, Xian; Shao, Lijing +3 more
Motivated by the old idea of using the Moon as a resonant gravitational wave (GW) detector, as well as the recent updates in modeling the lunar response to GWs, we reevaluate the feasibility of using a network of lunar seismometers to constrain the stochastic GW background (SGWB). In particular, using the updated model of the lunar response, we de…
Sensor noise in L I S A P a t h f i n d e r : Laser frequency noise and its coupling to the optical test mass readout
Mendes, L.; Russano, G.; Sanjuan, J. +84 more
The LISA Pathfinder (LPF) mission successfully demonstrated the feasibility of the technology needed for the future space borne gravitational wave observatory LISA. A key subsystem under study was the laser interferometer, which measured the changes in relative distance in between two test masses (TMs). It achieved a sensitivity of 32.0-1.7
Violation of the equivalence principle induced by oscillating rest mass and transition frequency, and its detection in atom interferometers
Wolf, Peter; Gué, Jordan; Hees, Aurélien
We present a theoretical investigation of the expected experimental signals produced by freely falling atoms with time oscillating mass and transition frequency. These oscillations could be produced in a variety of models, in particular, models of scalar dark matter nonuniversally coupled to the standard matter such as axionlike particles and dila…
Nano-Newton electrostatic force actuators for femto-Newton-sensitive measurements: System performance test in the LISA Pathfinder mission
Mendes, L.; Russano, G.; Nofrarias, M. +89 more
Electrostatic force actuation is a key component of the system of geodesic reference test masses (TM) for the LISA orbiting gravitational wave observatory and in particular for performance at low frequencies, below 1 mHz, where the observatory sensitivity is limited by stray force noise. The system needs to apply forces of order 10-9 N …