Probing the densest objects in the universe
We are a research group at the National Institute of Technology, Rourkela, India — working at the intersection of nuclear physics, astrophysics, gravitational waves, and dark matter to unravel the mysteries of neutron stars.
What we study
Equation of State of Neutron Stars
Deciphering dense matter at nuclear densities using relativistic mean-field models and observational constraints from LIGO, NICER, and pulsar timing.
Hyperons & Exotic Matter
Exploring strangeness-bearing particles — hyperons, delta baryons, and quarkyonic matter — and their effects on stellar structure, stability, and GW emission.
Gravitational Waves & Oscillations
Computing quasinormal modes, f- and p-mode frequencies, tidal deformability, and I-Love-Q relations linking to GW170817 and Einstein Telescope.
Dark Matter in Neutron Stars
Using neutron stars as cosmic dark matter laboratories — constraining WIMP, fermionic, and self-interacting dark matter through mass, radius, and oscillation observables.
Thermal Evolution
Investigating neutron star cooling, proto-NS evolution, and the role of temperature, entropy, and lepton fraction on nuclear matter properties.
Multi-Messenger Astrophysics
Bridging nuclear theory with EM, gravitational wave, and neutrino observations to constrain the neutron star equation of state at extreme densities.
Dr. Bharat Kumar
Bharat Kumar
Assistant Professor · Department of Physics & Astronomy, NIT Rourkela · since June 2020
M.Sc. Physics, AMU Aligarh · Ph.D. with S K Patra, IOP Bhubaneswar · Postdoc with Sukanta Bose (LIGO-India, IUCAA) · Postdoc with Takashi Nakatsukasa, University of Tsukuba, Japan
Citation count last verified via Google Scholar ↗ — click through for live, up-to-the-minute numbers.
Latest in neutron-star & GW astrophysics
Hand-picked recent developments in dense matter, gravitational-wave astronomy, and dark matter searches — updated periodically by the lab.
GWTC-4.0 catalog more than doubles GW detections
The LVK collaboration released GWTC-4.0, adding 128 new confirmed events from the second half of O4 and bringing the all-time total past 390 confirmed mergers, including new black hole–neutron star systems.
Construction begins on LIGO-India detector
Civil construction started in April 2026 on the LIGO-India facility, which will become the fifth major gravitational-wave interferometer and is projected to join the global network for the O5 run.
Mirror dark matter effects on NS tidal deformability
Jiao & Li construct a hadron–quark equation of state combined with mirror dark matter and show how the dark sector modifies tidal Love numbers and the 2M☉ constraint via Maxwell construction.
Probing NS equation of state via EMRIs in dark matter spikes
Karydas & collaborators show that LISA-band extreme mass-ratio inspirals through dense dark matter environments can, at high SNR, discriminate between neutron-star equations of state via relativistic dynamical friction.
Strongly-interacting dark matter admixed neutron stars
Dengler, Kulkarni, Maas & Radl use lattice QCD-like G2-gauge equations of state for strongly self-interacting dark matter and find masses of a few hundred MeV–GeV remain consistent with observed NS properties.
Intermediate Run IR1 planned for late 2026
LIGO, Virgo, and KAGRA are preparing a six-month intermediate observing run (IR1) beginning around October–November 2026, as a bridge toward the long-awaited O5 run with improved sensitivity.
For the very latest preprints see arXiv:astro-ph.HE ↗, nucl-th ↗, and LIGO News ↗
News
Congratulations to Pinku Routaray for successfully defending his PhD thesis and joining the Kavli Institute of Astronomy and Astrophysics, China as a postdoc!
Congrats to Pinku for Best Poster Award at the DAE High Energy Physics Symposium, BHU. Event ↗
Paper by Kalita, Routaray, Ghosh & Kumar on delta-baryons published in JCAP ↗
Pinku's paper on WIMP dark matter accepted in MNRAS ↗
Upcoming events
GWsNS-2026 — Gravitational Waves from Neutron Stars school, Roscoff, France.
Asian GW Astronomy Meeting (AGWAM 2026) — Chiang Mai, Thailand.
Multimessenger Astrophysics 2026 — 9th ICE Summer School, Barcelona, Spain.
Erice School — Neutrinos in Cosmology, Astro-, Particle & Nuclear Physics, Erice, Italy.
Current team members
PhD Students
Sayantan Ghosh
M.Sc., Banaras Hindu University
Selected publications
Probing the Impact of Delta-Baryons on Nuclear Matter and Non-Radial Oscillations in Neutron Stars
The Role of Adiabatic Sound Speeds in Neutron Star Radial Oscillations and Stability
Observable Signatures of a Quarkyonic Phase in Neutron Stars
Spacetime Curvature as a Probe of Exotic Core Phases in Neutron Stars within Modified Gravity
Join us
PhD Fellowship (DST WISE)
Positions in neutron star asteroseismology, dark matter admixed NSs, and multi-messenger astrophysics.
Apply via DST WISE ↗SERB-NPDF Fellowship
Postdoc in nuclear astrophysics, GW oscillations, or EoS constraints with LIGO/NICER data.
Apply via SERB ↗Own Fellowship? Join Us
If you have an external fellowship and wish to pursue research with us, get in touch directly.
kumarbh@nitrkl.ac.in ↗Contact
Dr. Bharat KumarMC202, Department of Physics & Astronomy
National Institute of Technology, Rourkela
Odisha 769008, India
Email: kumarbh@nitrkl.ac.in
Maps ↗
Support
Supported by the Science and Engineering Research Board (SERB), Government of India.
Part of the Department of Physics and Astronomy, NIT Rourkela.
