Dheeraj Pasham (DJ) earned his PhD from the University of Maryland College Park in 2014 working on X-ray and optical time series analysis of Ultraluminous X-ray sources (ULXs). He was supervised by Dr. Tod Strohmayer at NASA. From 2014-2016–as a postdoctoral associate at NASA Goddard Space Flight Center–he worked with Dr. Bradley Cenko on multi-wavelength analysis of tidal disruption events (TDEs). He moved to MIT as an Einstein fellow in 2016 where he has been working on tidal disruption flares and has been involved with NICER (Neutron star Interior Composition ExploreR) with Dr. Ron Remillard and Dr. Deepto Chakrabarthy. DJ was promoted to Research Scientist on 8/1/2019.

DJ is primarily an observer and uses multi-wavelength data (X-ray, optical, UV and Radio) to address many of the open questions about tidal disruption flares, viz., How and when does an accretion disk form after a star gets disrupted by a supermassive black hole? What drives a radio jet in a tidal disruption flare? How can we use data to measure the spin of a supermassive black hole in a TDE?

He also is interested in devising new observational techniques to measure the masses of the black holes in the so-called ultraluminous X-ray sources some of which may host the long-sought intermediate-mass black holes (masses in the range of a few 100-1000 solar masses).

He is also working on accreting neutron star systems to measure the masses and the radii of neutron stars which could enable us to constrain the equation of state of matter at the highest densities found in the Universe.

INSTRUMENTATION

Space-Based Observatories
In addition to those noted on the right:
XMM-Newton
Swift

Ground-Based Observatories
In addition to those noted on the right:
Discovery Channel Telescope (DCT)
Very Large Telescope (VLT)

RESEARCH

Science themes
In addition to those noted on the right:
Black Hole Accretion Disks and Jets