I'm a third-year physics PhD student at MIT. I am fortunate to be advised by Erin Kara and work closely with Kevin Burdge and Riccardo Arcodia.
I was an undergrad at Columbia, where I worked with Frits Paerels on X-ray astronomy and David Kipping on extrasolar planets, graduating in 2022. Before that, I grew up in Edison, New Jersey.
This website was last updated in May 2025.
e-mail: joheen (at) mit (dot) edu
Research Interests:
My research is in high-energy astrophysics, which provides a remarkable diversity of mysterious and exciting phenomena to explore. I study electromagnetic radiation produced in the vicinity of compact objects (e.g. black holes, white dwarfs), which is mediated by plasma physics, atomic physics, strong gravity/general relativity, and radiative transfer. The overarching goal of this work is to understand how compact objects form, evolve, influence their surroundings, and power some of the most energetic phenomena observed in nature. A (mostly accidental) theme of my current work is electromagnetic emission from low-frequency (~millihertz) gravitational wave sources. Some topics I work on are:
-Quasi-Periodic Eruptions (QPEs), a newly discovered type of recurring X-ray transient which may be the first-known electromagnetic counterparts to EMRIs. An enticing possibility is using them to map general relativistic precession effects within hundreds of gravitational radii of supermassive black holes. Here are some animations illustrating the timing modulation effects of accretion disk nodal precession and EMRI apsidal precession (the "Q" in QPE).
-Ultracompact binaries, which are the dominant millihertz gravitational wave sources in the Galaxy. They will allow uniquely the multi-messenger ("messengers" = light and gravitational waves) study of accretion disks, and are potentially the progenitors of Type Ia supernovae.
-Tidal Disruption Events, which are ideal laboratories to study turbulent accretion disks around supermassive black holes.
-X-ray astronomy, high performance computing, large-scale data analysis, Bayesian inference. I am also a member of the NICER science team.
Selected Publications:
Rapidly varying ionization features in a Quasi-periodic Eruption: a homologous expansion model for the spectroscopic evolution
Joheen Chakraborty, Peter Kosec, Erin Kara, Giovanni Miniutti, et al.
Astrophysical Journal, May 2025
[Paper]
[Press]
[Summary]
Discovery of extreme Quasi-Periodic Eruptions in a newly accreting massive black hole
Lorena Hernández-García, Joheen Chakraborty, Paula Sánchez-Sáez, Claudi Ricci, et al.
Nature Astronomy, Apr. 2025
[Paper]
[Press]
[Summary]
Discovery of Quasi-periodic Eruptions in the Tidal Disruption Event and Extreme Coronal Line Emitter AT2022upj: implications for the QPE/TDE fraction and a connection to ECLEs
Joheen Chakraborty, Erin Kara, Riccardo Arcodia, Johannes Buchner, et al.
Astrophysical Journal Letters, Apr. 2025
[Paper]
[Summary]
Expanding the ultracompacts: gravitational wave-driven mass transfer in the shortest-period binaries with accretion disks
Joheen Chakraborty, Kevin Burdge, Saul Rappaport, James Munday, et al.
Astrophysical Journal, Dec. 2024
[Paper]
Testing EMRI models for Quasi-periodic Eruptions with 3.5 years of monitoring eRO-QPE1
Joheen Chakraborty, Riccardo Arcodia, Erin Kara, Giovanni Miniutti, Margherita Giustini, et al.
Astrophysical Journal, Apr. 2024
[Paper]
[Summary]
[Talk]
Possible X-ray Quasi-periodic Eruptions in a tidal disruption event candidate
Joheen Chakraborty, Erin Kara, Megan Masterson, Margherita Giustini, Giovanni Miniutti, Richard Saxton
Astrophysical Journal Letters, Nov. 2021
[Paper]
[Press]
[Talk]
You can find my first-/second-author papers here, and all papers I've been on here. (arXiv version)
