Department of Physics and Astronomy
Montclair State University
1 Normal Ave.
Montclair, NJ 07043
+1 (973) 655-7797
ghoshs@montclair.edu
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Shaon Ghosh

Astrophysicist

  • EMAIL : ghoshs@montclair.edu
  • AFFILIATION : Montclair State University

Profile

Professional Summary

Dr. Shaon Ghosh is an assistant professor of physics and astronomy at the (department of physics and astronomy) of the Montclair State University. His research interests are in cataclysmic events like coalescences of neutron stars and black holes. Such events are strong emitters of gravitational-waves that are detectable by ground-based gravitational-waves detectors like the LIGO and Virgo. A subset of these events is also among the prime candidates of some of the most violent electromagnetic phenomenons in the universe like short duration Gamma-ray bursts and r-process powered Kilonovae. Coalescences of compact binaries with at least one neutron star is also a laboratory to study and constrain extreme matter. Neutron star equation of state (EoS) is a poorly constrained attribute a neutron star. Gravitational-wave observation, with a possible combination of observation of electromagnetic counterpart, can facilitate in putting strong constraints on the EoS. The prospects of a combination of gravitational-wave and EM observation hold promise for rich science in the near future. It will augment our understanding of gravity, radiative processes, magnetohydrodynamics, nuclear and particle physics, astrophysical rates, matter in extreme temperature and densities and, perhaps more excitingly, the possibility to unveil new unexplained phenomenon.

Research Interests

Source-properties inference

The information of many of the physical characteristics of the coalescing systems is encoded in the gravitational wave that we receive. Some of these information like, the probability that there is a neutron star in the binary or that there is tidally disrupted matter outside the final merger remnant, one can determine in real-time and inform the observers of them. Dr. Ghosh developed the infrastructure to conduct this analysis and this was used during LIGO-Virgo second observing run. This package, known and the EM-Bright package, is now used by the LIGO/Virgo collaboration to provide the source-properties information to electromagnetic observing partners via GCNs. The main challenge in providing this information in the low-latency is the fact that the recovered parameters from the template-based searches conducted by the various low-latency compact binary coalescence pipelines are prone to large statistical and systematic errors. Thus, any inference in the low-latency will have to compensate for this error. EM-Bright attempts to do that using supervised machine learning (k-nearest neighbor). Studies conducted by Dr. Ghosh and his collaborators have revealed that this improves the speed of inference significantly for low-mass binaries (which are the most interesting ones for most electromagnetic observers). This is also much more robust than the technique we used in O2, which involved characterizing the ambiguity region of the parameter space by an ellipsoid and populating this region by points, which served as surrogate for posterior samples.

Teaching

Astronomy-103

Introductory astronomy for undergraduate students. Topics covered:
The scientific method, Celestial coordinates, The phases of the moon and eclipses, The history of astronomy, Light and telescopes, The Solar System, The Sun, Stars: properties and types, Stellar formation and evolution, Stellar explosions: Nova, Supernova, Gamma Ray Bursts, Compact objects: White dwarfs, Neutron stars, Pulsars, Black holes, Gravitational waves, Galaxies, AGN, Quasars, Cosmology, The Universe.
Book available at OpenStax.

Work Experience

PREVIOUS JOBS

Assistant professor of physics and astronomy

Montclair State University
JANUARY 2020 - Present

Postdoctoral research associate

University of Wisconsin - Milwaukee
NOVEMBER 2016 - JANUARY 2020

  • Co-Chair of the LIGO-Virgo’s low-latency group.
  • Design and implementation of EM-Bright pipeline. Integration into LIGO and Virgo’s low-latency data analysis infrastructure.
  • Devolopment of neutron star equation of state model selection method.
  • Development of optimal tiling and observing strategy of gravitational wave and Fermi GRB triggers for the Zwicky Transient Facility.
  • Development of generic optimal tiling strategy for radio telescopes like ASKAP.
  • Zwicky Transient Facility (ZTF) simulation. Gravitational wave sky-localization and optical counterpart study using LIGO and virgo data.
  • Development of EM follow-up schedular for the BlackGEM telescope.
  • Rapid parameter estimation of coalescing compact binaries.

Postdoctoral researcher

Radboud University, Nijmegen, The Netherlands
SEPTEMBER 2013 - SEPTEMBER 2016

  • Large scale scenario study for neutron star-black hole binary systems.
  • Sky-localization study for highly precessing compact binary coalescing systems.
  • Participation in the parameter estimation efforts of the first binary black hole detection GW150914
  • EM follow-up advocate during LIGO-Virgo’s first observing run (O1)
  • Analysis of raw data from GW150914 to give a “simple proof" that the observed trigger was indeed from a binary black hole coalescence.
  • Developing infrastructure (software) and observing strategies for optical follow-up of gravitational wave candidates for the BlackGEM telescope array.
  • Parameter estimation of gravitational wave triggers in presence of waveform mismatch.
  • Working in the EM-follow-up and parameter estimation sub-groups of the compact binary coalescence group as a member of Virgo scientific collaboration.

Education

ACADEMIC CAREER

Ph.D. in Physics

Washington State University, Pullman
GRADUATED IN 2013

Dr. Ghosh conducted research on detection of gravitational-wave from external triggers of short duration gamma-ray bursts during his Ph.D. He developed a technique of detection of gravitational-wave in LIGO data using a technique that coherently combines the data across three gravitational-wave detectors, thus maximizing the network's ability to discern spurious noise artificts from astrophysical signals. Link to the thesis.

Master of Science in Physics

Indian Institute of Technology, Kharagpur
GRADUATED IN 2006

Bachelor of Science (Honours in Physics)

University of Calcutta
GRADUATED IN 2004