146 citations · 896 across the 52 of their papers we have counts for
30 papers · 1 filter
An intrinsic decline of accretion activity in GRS 1915+105
Poshak Gandhi, Peter G. Boorman
The canonical microquasar GRS 1915+105 is exhibiting unprecedented changes in its multiwavelength properties since 2018. Recent pointed observations with NuSTAR in November 2025 ha…
Transient Relativistic Iron Emission Line from an X-ray Flaring Supermassive Black Hole
Xiurui Zhao, Marco Ajello, Francesca Civano +16
We report the discovery of the first transient relativistic iron Kα line in an Active Galactic Nucleus (AGN) J1047+5907. The line was detected 21.5 days (rest-frame) after an X-ray…
A comprehensive search for high-velocity X-ray sources: New compact object binary candidates in the Gaia era
Yue Zhao, Poshak Gandhi, Christian Knigge +6
We perform a comprehensive search for high-velocity X-ray sources with large X-ray/optical flux ratios (), identifying candidates for interacting black h…
NuSTAR Detection of an Absorption Feature in ESP 39607: Evidence for an Ultra-Fast Inflow?
Alessandro Peca, Michael J. Koss, Roberto Serafinelli +4
We report the serendipitous discovery of an absorption feature at 4.8 keV in the NuSTAR spectra of ESP 39607, a Seyfert 2 galaxy at , observed in May 2023 and August 202…
NuSTAR observations of a varying-flux quasar in the Epoch of Reionization
Lea Marcotulli, Thomas Connor, Eduardo Bañados +13
With enough X-ray flux to be detected in a 160s scan by SRG/eROSITA, the quasar CFHQS J142952+544717 is, by far, the most luminous X-ray source known at . We pres…
An Intermediate Mass Black Hole Hidden Behind Thick Obscuration
Peter G. Boorman, Daniel Stern, Roberto J. Assef +12
Recent models suggest approximately half of all accreting supermassive black holes (SMBHs; 10 M) are expected to undergo intense growth phase…