152 citations · 2.4k across the 65 of their papers we have counts for
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Testing General Relativity with NuSTAR data of Galactic Black Holes
Ashutosh Tripathi, Yuexin Zhang, Askar B. Abdikamalov +5
Einstein's theory of General Relativity predicts that the spacetime metric around astrophysical black holes is described by the Kerr solution. In this work, we employ state-of-the-…
Constraints on the rate of supernovae lasting for more than a year from Subaru/Hyper Suprime-Cam
Takashi J. Moriya, Ji-an Jiang, Naoki Yasuda +15
Some supernovae such as pair-instability supernovae are predicted to have the duration of more than a year in the observer frame. To constrain the rates of supernovae lasting for m…
The Awakening Beast in the Seyfert 1 Galaxy KUG 1141+371 I
Jiachen Jiang, Huaqing Cheng, Luigi C. Gallo +10
KUG 1141+371 is a Seyfert 1 galaxy that shows a simultaneous flux increase in the optical and UV bands in the past decade. For instance, the latest Swift observation in 2019 shows…
Towards precision measurements of accreting black holes using X-ray reflection spectroscopy
Cosimo Bambi, Laura W. Brenneman, Thomas Dauser +14
Relativistic reflection features are commonly observed in the X-ray spectra of accreting black holes. In the presence of high quality data and with the correct astrophysical model,…
The Origin of X-ray Emission in the Gamma-ray emitting Narrow-Line Seyfert 1 1H 0323+342
Sergio A. Mundo, Erin Kara, Edward M. Cackett +7
We present the results of X-ray spectral and timing analyses of the closest gamma-ray emitting narrow-line Seyfert 1 (-NLS1) galaxy, 1H 0323+342. We use observations from a rece…
Calcium-rich Transient SN 2019ehk in A Star-Forming Environment: Yet Another Candidate for An Ultra-Stripped Envelope Supernova
Tatsuya Nakaoka, Keiichi Maeda, Masayuki Yamanaka +20
We present optical and near-infrared observations of SN~Ib~2019ehk. We show that it evolved to a Ca-rich transient according to its spectral properties and evolution in late phases…
The HSC-SSP Transient Survey: Implications from Early Photometry and Rise Time of Normal Type Ia Supernovae
Ji-an Jiang, Naoki Yasuda, Keiichi Maeda +9
With a booming number of Type Ia supernovae (SNe Ia) discovered within a few days of their explosions, a fraction of SNe Ia that show luminosity excess in the early phase (early-ex…
Rapidly Evolving Transients from the Hyper Suprime-Cam SSP Transient Survey
Yusuke Tampo, Masaomi Tanaka, Keiichi Maeda +9
Rapidly evolving transients form a new class of transients which show shorter timescales of the light curves than those of typical core-collapse and thermonuclear supernovae. We pe…
A dynamic black hole corona in an active galaxy through X-ray reverberation mapping
William N. Alston, Andrew C. Fabian, Erin Kara +18
X-ray reverberation echoes are assumed to be produced in the strongly distorted spacetime around accreting supermassive black holes. This signal allows us to spatially map the geom…