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John Tomsick

Research ScientistUniversity of CaliforniaSpace Sciences Laboratory
Work Phone: 510-725-5591
Photo of John Tomsick


Since 1994, John has been working in astrophysics, including observations and instrumentation, at Columbia University, UC San Diego, and UC Berkeley. John’s primary work is to use X-ray and multi wavelength observations as a probe of the regions of strong gravity near accreting black holes and neutron stars. John was the chair of the RXTE Users Group, and he has been a member of the Chandra Users Committee and the INTEGRAL Users Group. He is currently a leading member of the NuSTAR Science Team, being the chair of the Galactic Binaries Working Group and the NuSTAR Users Group. John is a member of the 3G collaboration, which is developing the science case for the next generation of ground-based gravitational-wave detectors. John is also the Project Scientist for the Compton Spectrometer and Imager (COSI/COSI-X) balloon mission and is a member of the Physics of the Cosmos Program Analysis Group (PhysPAG) Executive Committee.

Between 1998 and 2019, John has been first author or co-author on 257 refereed publications, which have been cited over 8200 times. The work has included results using NuSTAR, XMM-Newton, Chandra, INTEGRAL, Swift, VLT, VLA, COSI, and more to observe accreting black holes and neutron stars, cataclysmic variables, AGN, and Sgr A*. The topics include black hole spins and warped accretion disks as well as constraints on populations of High-Mass X-ray Binaries.