About

Shami Chatterjee is an Associate Professor in the Department of Astronomy at Cornell University, affiliated with the Cornell Center for Astrophysics and Planetary Science and the Carl Sagan Institute. He earned his Ph.D. in Astronomy from Cornell University in 2003, working with Jim Cordes. Prior to his current position, he held roles including Principal Research Scientist and Research Professor at Cornell, a Research Scientist and Queen Elizabeth II Fellow at the Australia Telescope National Facility, a University Postdoctoral Fellow at the University of Sydney, and a Jansky Fellow at the Harvard-Smithsonian Center for Astrophysics and the National Radio Astronomy Observatory. His research focuses on pulsars, fast radio bursts (FRBs), and gravitational waves, with significant contributions to the detection of a stochastic background of gravitational waves at nanohertz frequencies through the NANOGrav collaboration, using pulsars as precise astrophysical clocks. He was part of the team that discovered the repeating fast radio burst FRB 121102 at Arecibo and localized it to a distant dwarf galaxy, revealing its unique properties including extreme Faraday rotation indicative of an intensely magnetized environment possibly near a massive black hole or a pulsar wind nebula. Chatterjee's work also includes testing the Principle of Equivalence using a pulsar in a triple system with two white dwarfs, and discovering extraordinary pulsar systems with the Arecibo radio telescope, such as an eccentric binary pulsar and a binary neutron star pair with asymmetric masses relevant to LIGO-detected neutron star mergers. He has contributed to public engagement and community efforts, including running the FRB Community Newsletter and maintaining resources for pulsar research.

Research topics

• Physics
• Astrophysics
• Astronomy
• Computer Science
• Artificial Intelligence
• Optics
• Quantum mechanics
• Condensed matter physics
• Computational physics
• Data science
• Meteorology
• Mathematics
• Environmental science

Selected publications

• Fast Radio Burst Community Newsletter - Volume 7, Issue 04

  eCommons (Cornell University) · 2026-05-05

  articleOpen accessSenior author

  We acknowledge support from the Cornell University Library, the National Science Foundation (NSF), the NASA Hubble Fellowship Program, and the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) at Northwestern University.

  PublisherOA PDFDOI

• Fast Radio Burst Community Newsletter - Volume 7, Issue 2

  eCommons (Cornell University) · 2026-04-22

  articleOpen accessSenior author
  PublisherOA PDFDOI

• Fast Radio Burst Community Newsletter - Volume 7, Issue 1

  eCommons (Cornell University) · 2026-04-22

  articleOpen accessSenior author
  PublisherOA PDFDOI

• Inference on inner galaxy structure via gravitational waves from supermassive binaries

  Nature Astronomy · 2026-02-05 · 1 citations

  preprint
  PublisherDOI

• Fast Radio Burst Community Newsletter - Volume 7, Issue 3

  eCommons (Cornell University) · 2026-04-22

  articleOpen accessSenior author
  PublisherOA PDFDOI

• The NANOGrav 15 yr Data Set: Search for Gravitational-wave Memory

  The Astrophysical Journal · 2025-06-23 · 3 citations

  articleOpen access

  Abstract We present the results of a search for nonlinear gravitational-wave (GW) memory in the NANOGrav 15 yr data set. We find no significant evidence for memory signals in the data set, with a maximum Bayes factor of 3.1 in favor of a model including memory. We therefore place upper limits on the strain of potential GW memory events as a function of sky location and observing epoch. We find upper limits that are not always more constraining than previous NANOGrav results. We show that it is likely due to the increase in common red noise between the 12.5 and 15 yr NANOGrav data sets.

  PublisherDOI

• CHIME/Fast Radio Burst/Pulsar Discovery of a Nearby Long-period Radio Transient with a Timing Glitch

  The Astrophysical Journal Letters · 2025-09-04 · 15 citations

  articleOpen accessCorresponding

  Abstract We present the discovery of a 421 s long period transient using the CHIME telescope, CHIME J0630+25. The source is localized to R.A. = 06:30:38.4 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo>±</mml:mo> <mml:mn>1</mml:mn> <mml:mo accent="false">′</mml:mo> </mml:math> decl. = 25:26:23 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo>±</mml:mo> <mml:mn>1</mml:mn> <mml:mo accent="false">′</mml:mo> </mml:math> using voltage data acquired with the CHIME baseband system. A timing analysis shows that a model including a glitch is preferred over a nonglitch model with dF / F = 1.3 × 10 −6 , consistent with other glitching neutron stars. The timing model suggests a surface magnetic field of ∼1.5 × 10 15 G and a characteristic age of ∼1.28 × 10 6 yr. A separate line of evidence to support a strong local magnetic field is an abnormally high rotation measure of RM = −347.8(6) rad m −2 relative to CHIME J0630+25’s modest dispersion measure of 22(1) pc cm −2 , implying a dense local magneto-ionic structure. As a result, we believe that CHIME J0630+25 is a magnetized, slowly spinning, isolated neutron star. This marks CHIME J0630+25 as the longest period neutron star and the second-longest period neutron star with an inferred magnetar-like field. Based on dispersion measure models and comparison with pulsars with distance measurements, CHIME J0630+25 is located at a nearby distance of 170 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow/> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>100</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>310</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> pc (95.4%), making it an ideal candidate for follow-up studies.

  PublisherDOI

• A VLBI Software Correlator for Fast Radio Transients

  The Astronomical Journal · 2025-06-25 · 5 citations

  articleOpen access

  Abstract One major goal in fast radio burst science is to detect fast radio bursts (FRBs) over a wide field of view without sacrificing the angular resolution required to pinpoint them to their host galaxies. Wide-field detection and localization capabilities have already been demonstrated using connected-element interferometry; the CHIME/FRB Outriggers project will push this further using widefield cylindrical telescopes as widefield outriggers for very long baseline interferometry (VLBI). This paper describes an offline VLBI software correlator written in Python for the CHIME/FRB Outriggers project. It includes features well-suited to modern widefield instruments like multibeaming/multiple phase center correlation, pulse gating including coherent dedispersion, and a novel correlation algorithm based on the quadratic estimator formalism. This algorithm mitigates sensitivity loss that arises in instruments where the windowing and channelization is done outside the VLBI correlator at each station, which accounts for a 30% sensitivity drop away from the phase center. Our correlation algorithm recovers this sensitivity on both simulated and real data. As an end-to-end check of our software, we have written a preliminary pipeline for VLBI calibration and single-pulse localization, which we use in Lanman et al. to verify the astrometric accuracy of the CHIME/FRB Outriggers array.

  PublisherDOI

• A milliarcsecond localization associates FRB 20190417A with a compact persistent radio source and an extreme magneto-ionic environment

  arXiv (Cornell University) · 2025-09-05 · 2 citations

  preprintOpen access

  We report the milliarcsecond localization of a high (1379 pc/cc) dispersion measure (DM) repeating fast radio burst, FRB 20190417A. Combining European VLBI Network detections of five repeat bursts, we confirm the FRB's host to be a low-metallicity, star-forming dwarf galaxy at z = 0.12817, similar to the hosts of FRBs 20121102A, 20190520B and 20240114A. We also confirm that it is associated with a previously reported persistent radio source (PRS), which is compact on milliarcsecond scales. Visibility-domain model fitting constrains the transverse physical size of the PRS to &lt; 23 pc and yields an integrated flux density of 191(39) microJy at 1.4 GHz. Though we do not find significant evidence for DM evolution, FRB 20190417A exhibits a time-variable rotation measure (RM) ranging between +3958(11) and +5061(24) rad/m2 over three years. We find no evidence for intervening galaxy clusters in the FRB's line-of-sight and place a conservative lower limit on the rest-frame host DM contribution of 1228 pc/cc (90% confidence) -- the largest known for any FRB so far. This system strengthens the emerging picture of a rare subclass of repeating FRBs with large and variable RMs, above-average host DMs, and luminous PRS counterparts in metal-poor dwarf galaxies. Our results suggest that these systems are the result of environmental selection, or a distinct engine for FRB emission.

  PublisherOA PDFDOI

• GReX: An Instrument Overview and New Upper Limits on the Galactic FRB Population

  Publications of the Astronomical Society of the Pacific · 2025-07-01 · 2 citations

  articleOpen accessCorresponding

  Abstract We present the instrument design and initial results for the Galactic Radio Explorer, an all-sky monitor for exceptionally bright transients in the radio sky. This instrument builds on the success of STARE2 to search for fast radio bursts (FRBs) from the Milky Way and its satellites. This instrument has deployments across the globe, with wide sky coverage and searching down to 32 μ s time resolution, enabling the discovery of new super giant pulses. Presented here are the details of the hardware and software design of the instrument, performance in sensitivity and other key metrics, and experience in building a global-scale, low-cost experiment. We follow this discussion with experimental results on validation of the sensitivity via hydrogen-line measurements. We then update the rate of Galactic FRBs based on non-detection in the time since FRB 200428. Our results suggest FRB-like events are even rarer than initially implied by the detection of a MJy burst from SGR J1935+2154 in 2020 April.

  PublisherDOI

Recent grants

• Radio Bursts and Gravity from Parsecs to Gigaparsecs

  NSF · $586k · 2018–2021

• Collaborative Research: Booming or Beaming? Sorting out the Dynamic Radio Universe

  NSF · $269k · 2010–2015

Frequent coauthors

• J. M. Cordes

  426 shared

• G. Desvignes

  302 shared

• S. M. Ransom

  240 shared

• M. A. McLaughlin

  234 shared

• Ue‐Li Pen

  227 shared

• I. H. Stairs

  University of British Columbia

  218 shared

• J. W. T. Hessels

  218 shared

• M. Krämer

  212 shared

Labs

• Shami Chatterjee's LabPI

Education

• Ph.D.

  Cornell University

  2003

• B.Tech., Electronics and Communications

  Indian Institute of Technology Madras

  1996