People

"The hardest problems of pure and applied science can only be solved by the open collaboration of the world-wide scientific community."

-Kenneth G. Wilson, Nobel laureate and Caltech alumnus

Our Faculty

Dr. Fiona Harrison

Dr. Fiona Harrison is the California Institute of Technology (Caltech) Benjamin M. Rosen Professor of Physics, and the Kent and Joyce Kresa Leadership Chair of the Division of Physics, Mathematics and Astronomy. Dr. Harrison’s research is focused on the study of energetic phenomena ranging from gamma-ray bursts, black holes on all mass scales, to neutron stars and supernovae. Currently she is principal investigator for NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR). She received her Ph.D. in physics from the University of California, Berkeley, and went to Caltech in 1993 as a Robert A. Millikan Prize Fellow in Experimental Physics.

  • fiona[at]srl[dot]caltech[dot]edu
Dr. Javier Garcia (he/him)

Research Assistant Professor of Physics

I build models using radiative transfer, general relativity, and laboratory astrophysics to simulate the X-rays reflected from accretion disks around black holes and neutron stars.

  • javier[at]caltech[dot]edu

Technical and Administrative Staff

Dr. Murray Brightman (he/him)

Staff Scientist

I am a staff scientist at the NuSTAR Science Operations Center. My duties include generating and delivering the pointing commands to the spacecraft, archiving and cataloging observational data, and calibration. My research interests include X-ray transients, ultraluminous X-ray sources, and heavily obscured active galactic nuclei.

  • murray[at]srl[dot]caltech[dot]edu
Dr. Hannah Earnshaw (they/them)

Staff Scientist

Hannah's primary research interest is in ultraluminous X-ray sources and other accreting X-ray binaries in nearby galaxies. They are also part of the team responsible for calibration and upkeep of the NuSTAR telescope.

  • hpearn[at]caltech[dot]edu
Dr. Karl Forster

Manager, NuSTAR Science Operations Center

Karl supervises the operation of the NuSTAR space telescope, ensuring that scientists around the world obtain the observations requested for their investigations, often leading coordination with other telescopes in space and on the ground.

  • krl[at]srl[dot]caltech[dot]edu
Dr. Brian Grefenstette (he/him)

Research Scientist

I am one of the principle mission scientists for NuSTAR and lead the NuSTAR calibration efforts. I use NuSTAR and other X-ray telescopes to study a wide range of astrophysical phenomena, from the leftover remnants of exploding stars to flares from the Sun and high energy emission from X-ray binaries.

  • bwgref[at]srl[dot]caltech[dot]edu
Hiromasa Miyasaka

Senior Staff Scientist

I am a detector scientist for NuSTAR CZT detector as well as many other radiation detectors. I have been studying CZT/CdTe solid-state pixel detectors for NASA’s future high-energy X-ray missions as part of an APRA program. I have also participate to develop the particles detector for NASA’s STEREO and Parker Solar Probe mission. I am currently working on to develop the detector readout system for the SPHEREx mission.

  • miyasaka[at]srl[dot]caltech[dot]edu
Dr. Daniel Stern (he/him)

NuSTAR Project Scientist

I primarily study extreme supermassive black holes at a variety of wavelengths, including very distant ones, heavily enshrouded ones, and ones that are rapidly changing in brightness.

  • daniel[dot]k[dot]stern[at]gmail[dot]com

Our Postdocs

Dr. Oluwashina (Shina) Adegoke

Postdoctoral Research Associate

I study the accretion flow properties of blackhole X-ray binaries during their outburst evolution through spectro-temporal analysis of their broadband X-ray observation. I am also interested in the interplay between the broadband electromagnetic radiation emitted from the different regions in the immediate vicinity of active galactic nuclei and how they can be used to constrain the physical properties of these systems.

  • oadegoke[at]caltech[dot]edu
Dr. Peter Boorman (he/him)

Postdoctoral Research Associate

I study the structure and evolution of the environment surrounding growing supermassive black holes with broadband X-ray spectral analysis and multi-wavelength observations. This includes finding and classifying black holes that grow behind thick layers of obscuring material, as well as analysing the growth of black holes across a broad range of mass, luminosity and accretion rate. I'm also interested in new ways to analyse astrophysical data including parameter exploration and data visualisation.

  • boorman[at]caltech[dot]edu
Dr. Amruta Jaodand (she/her)

Postdoctoral Research Associate

I study neutron stars using multi-wavelength observations to understand their evolution and interactions with other stars in compact binaries.

  • ajaodand[at]caltech[dot]edu
Dr. Margaret Lazzarini (she/her)

Postdoctoral Research Associate

I am a National Science Foundation Astronomy & Astrophysics Postdoctoral Fellow in the NuSTAR group at Caltech. I use multiwavelength observations of high mass X-ray binaries in nearby galaxies to constrain theoretical models of massive binary stellar evolution.

  • mlazz[at]caltech[dot]edu
Dr. Labani Mallick (she/her)

Postdoctoral Research Associate

My research focuses on intermediate-mass and supermassive black holes that accrete matter from their host galaxies. I primarily study the X-rays emitted from the innermost region of the accretion flow. I develop and apply novel spectral-timing models and methods to black hole observations to extend our census of known parameters into the domains key to the black hole-galaxy co-evolution.

  • lmallick[at]caltech[dot]edu
Dr. Ed Nathan

Postdoctoral Research Associate

My research is on black hole accretion, with a particular focus on reflection modelling and spectral-timing analysis. Here at Caltech I am working on the development of new XILLVER reflection models, including adding polarisation information.

  • enathan[at]caltech[dot]edu

Our Graduate Students

Yuhan Yao (she/her)

Graduate Student

I am interested in various types of high energy transients --- tidal disruption events, X-ray binaries, and stellar explosions. To explore these phenomena, I use the Zwicky Transient Facility (ZTF) and the SRG X-ray satellite as discovery engines, and conduct detailed follow up observations using other facilities including NuSTAR!

  • yyao[at]astro[dot]caltech[dot]edu
Yuanze Ding

Graduate Student

Black hole, neutron star…I am interested in the most powerful objects in the Universe. I have been working on X-ray binary and Active Galactic Nucleus (AGN) with X-ray satellites since I was an undergrad. My current research includes both theoretical and observational work, like modeling accretion disk reflection and studying AGN-Galaxy co-evolution with X-ray telescopes.

  • yding[dot]caltech[dot]edu