activity
20242026
collaborators

7 papers

gr-qc2026

Improved Constraints on Non-Kerr Deviations from Binary Black Hole Inspirals Using GWTC-4 Data

Debtroy Das, Swarnim Shashank, Cosimo Bambi

Gravitational wave (GW) observations of binary black hole (BBH) mergers provide a unique opportunity to probe the nature of spacetime in the strong-field and dynamical regime. We p…

astro-ph.HE2026

Modeling X-ray reflection spectra from returning radiation: application to 4U 163047

Kostas Kourmpetis, Shafqat Riaz, Honghui Liu +6

Returning radiation is thought to play a key role in disk illumination of black hole X-ray binaries in the high-soft state, yet it has not been fully incorporated into XSPEC reflec…

gr-qc2025

Testing black hole metrics with binary black hole inspirals

Zhe Zhao, Swarnim Shashank, Debtroy Das +1

Gravitational wave astronomy has opened an unprecedented window onto tests of gravity and fundamental physics in the strong-field regime. In this study, we examine a series of well…

astro-ph.HE2025

Spin Constraints on 4U 1630-47 via combined Continuum Fitting and Reflection methods: a comparative study using Frequentist and Bayesian statistics

Debtroy Das, Honghui Liu, Zuobin Zhang +5

We present a comprehensive Bayesian spectral analysis of the black hole X-ray binary 4U 1630-47 during its 2022 outburst, using simultaneous NICER and NuSTAR observations. Using th…

gr-qc2025

Probing missing physics from inspiralling compact binaries via time-frequency tracks

Debtroy Das, Soumen Roy, Anand S. Sengupta +1

The orbital evolution of binary black hole (BBH) systems is determined by the component masses and spins of the black holes and the governing gravity theory. Gravitational wave (GW…

astro-ph.GA2024

Gravitational Wave Astronomy With TianQin

En-Kun Li, Shuai Liu, Alejandro Torres-Orjuela +50

The opening of the gravitational wave window has significantly enhanced our capacity to explore the universe's most extreme and dynamic sector. In the mHz frequency range, a divers…