Kavli Affiliate: Dheeraj R. Pasham
| First 5 Authors: Shubham Kejriwal, Vojtech Witzany, Michal Zajacek, Dheeraj R. Pasham, Alvin J. K. Chua
| Summary:
Extreme-mass-ratio inspirals (EMRIs) are one of the primary targets for the
recently adopted millihertz gravitational-wave (GW) observatory LISA. Some
previous studies have argued that a fraction of all EMRIs form in matter-rich
environments, and can potentially explain the dozens of soft X-ray band ($sim
10^{-1} rm keV$), low-frequency ($sim 0.1$ mHz) periodic phenomena known as
quasi-periodic eruptions (QPEs) and quasi-periodic oscillations (QPOs). Here,
using a representative EMRI population retrofitted with cutoffs on LISA-band
SNRs and luminosity distances to account for the sensitivity of current
instruments, we estimate the mean frequency band in which QPEs and QPOs
originating from detectable LISA EMRIs may be emitting an X-ray signal
“today” (i.e., in 2024) to be $0.46 pm 0.22$ mHz. We also model the
well-known QPO source, RE J1034+396, which falls in this frequency band, as an
EMRI assuming its primary black hole mass to be $10^6-10^7 M_odot$. Through a
prior-predictive analysis, we estimate the orbiting compact object’s mass to be
$46^{+ 10}_{-40} M_odot$ and the source’s LISA-band SNR as $approx 14$,
highlighting it as a candidate multi-messenger EMRI target. We also highlight
the role of current and near-future X-ray and UV observatories in enabling
multi-messenger observations of EMRIs in conjunction with LISA, and conclude
with a discussion of caveats of the current analysis, such as the exclusion of
eccentricity and inclination from the model, and the measurability of sub-solar
mass compact object EMRIs.
| Search Query: ArXiv Query: search_query=au:”Dheeraj R. Pasham”&id_list=&start=0&max_results=3