LISA Symposium XIV Parallel D EMRIs part 1 @LISAcommunity

Uploaded August 2022 | Updated September 2026, 2 hours ago

LISA Symposium XIV Parallel D EMRIs part 1

$Bayesian Time Delay Interferometry for Orbiting LISA Laser frequency noise (LFN) due to unequal separations between spacecraft is the loudest source of noise expected in the LISA mission at 107 times greater magnitude than the typical strain expected for LISA GW signals. Time-delay interferometry (TDI) suppresses LFN to an acceptable level by linearly combining measurements from individual spacecraft delayed by durations that correspond to their relative separations. Knowledge of the delay durations is crucial for TDI effectiveness, and it’s been shown that they can be estimated from the raw phasemeter data using fractional delay interpolation (FDI), allowing for TDI implementation during the post-processing of data (time-delay interferometric ranging, TDIR) once data is telemetered to Earth. This work performs TDIR using a Markov Chain Monte Carlo algorithm. Including TDIR parameters in the LISA data model as part of a global fit analysis pipeline produces GW inferences that are marginalized over uncertainty in the spacecraft separations. Here we extend previous studies to now use data simulated by LISA Instrument, and to estimate the time-dependent delay durations for the 2nd-generation TDI combinations that account for the orbital motion of the spacecraft. The potential for an independent reconstruction of the spacecraft orbits is also explored. Authors: Jessica Page (Presenting) University of Alabama Huntsville, Huntsville, AL, USA$

$Searching for primordial black holes with stochastic gravitational-wave background Searching for primordial black holes with stochastic gravitational-wave background Yi-Fan Wang, Qing-Guo Huang,Tjonnie G.F. Li,Shihong Liao Assuming that primordial black holes compose a fraction of dark matter, some of them may accumulate at the center of galaxy and perform a prograde or retrograde orbit against the gravity pointing towards the center exerted by the central massive black hole. If the mass of primordial black holes is of the order of stellar mass or smaller, such extreme mass ratio inspirals can emit gravitational waves and form a background due to incoherent superposition of all the contributions of the Universe. We investigate the stochastic gravitational-wave background energy density spectra from the directional source, the primordial black holes surrounding Sagittarius A of the Milky Way, and the isotropic extragalactic total contribution, respectively. As will be shown, the resultant stochastic gravitational-wave background energy density shows different spectrum features such as the peak positions in the frequency domain for the above two kinds of sources. Detection of stochastic gravitational-wave background with such a feature may provide evidence for the existence of primordial black holes. Conversely, a null searching result can put constraints on the abundance of primordial black holes in dark matter.$

Energy dependence of galactic cosmic-ray variations

LISA Symposium XIV Parallel B Multi-Messenger Astrophysics and SMBHs Part 1

The Gravitational Signature of Asteroid Populations on LISA Orbits

Enhanced noise suppression for LISA by combining cavity and arm locking control systems

Action-angle coordinates for black hole geodesics and their use in EMRIs

The Zwicky Transient Facility high-cadence Galactic Plane survey and its implications for LISA

LISA, Extreme Mass Ratio Inspirals, and new fundamental fields in the gravity sector