93 citations · 744 across the 23 of their papers we have counts for
24 papers
High-energy neutrinos from shocked circumnuclear material around optically-bright and infrared-only tidal disruption events
Mainak Mukhopadhyay, Shigeo S. Kimura, Tatsuya Matsumoto
Tidal disruption events (TDEs) can launch sub-relativistic outflows that drive shocks into the surrounding circumnuclear material (CNM), providing a natural site for cosmic ray (CR…
From Discovery to the First Month of the Type II Supernova 2023ixf: High and Variable Mass Loss in the Final Year before Explosion
Daichi Hiramatsu, Daichi Tsuna, Edo Berger +22
We present the discovery of the Type II supernova SN 2023ixf in M101 and follow-up photometric and spectroscopic observations, respectively, in the first month and week of its evol…
Multiple Peaks and a Long Precursor in the Type IIn Supernova 2021qqp: An Energetic Explosion in a Complex Circumstellar Environment
Daichi Hiramatsu, Tatsuya Matsumoto, Edo Berger +14
We present optical photometry and spectroscopy of the Type IIn supernova (SN) 2021qqp. Its unusual light curve is marked by a long precursor for days, a rapid increase…
Swift J1644+57 as an off-axis Jet
Paz Beniamini, Tsvi Piran, Tatsuya Matsumoto
One of the intriguing puzzles concerning Swift J1644+57, the first jetted tidal disruption event (TDE) discovered, is the constant increase in its jet energy, as implied by radio o…
Synchrotron Afterglow Model for AT 2022cmc: Jetted Tidal Disruption Event or Engine-Powered Supernova?
Tatsuya Matsumoto, Brian D. Metzger
AT 2022cmc is a luminous optical transient ( erg s) accompanied by decaying non-thermal X-rays (peak duration days and isotropic e…
Generalized equipartition method from an arbitrary viewing angle
Tatsuya Matsumoto, Tsvi Piran
The equipartition analysis yields estimates of the radius and energy of synchrotron self-absorbed radio sources. Here we generalize this method to relativistic off-axis viewed emit…
Supernova Precursor Emission and the Origin of Pre-Explosion Stellar Mass-Loss
Tatsuya Matsumoto, Brian D. Metzger
A growing number of core collapse supernovae (SNe) which show evidence for interaction with dense circumstellar material (CSM) are accompanied by "precursor" optical emission risin…
Light Curve Model for Luminous Red Novae and Inferences about the Ejecta of Stellar Mergers
Tatsuya Matsumoto, Brian D. Metzger
The process of unstable mass transfer in a stellar binary can result in either a complete merger of the stars or successful removal of the donor envelope leaving a surviving more c…
What powers the radio emission in TDE AT2019dsg: a long-lived jet or the disruption itself?
Tatsuya Matsumoto, Tsvi Piran, Julian H. Krolik
The tidal disruption event AT2019dsg was observed from radio to X-rays and was possibly accompanied by a high-energy neutrino. Previous interpretations have focused on continued in…
Radio constraint on outflows from tidal disruption events
Tatsuya Matsumoto, Tsvi Piran
Radio flares from tidal disruption events (TDEs) are generally interpreted as synchrotron emission arising from the interaction of an outflow with the surrounding circumnuclear med…
Limits on mass outflow from optical tidal disruption events
Tatsuya Matsumoto, Tsvi Piran
The discovery of optical/UV tidal disruption events (TDEs) was surprising. The expectation was that, upon returning to the pericenter, the stellar-debris stream will form a compact…
Searching for the radio remnants of short duration gamma-ray bursts
Roberto Ricci, Eleonora Troja, Gabriele Bruni +8
Neutron star mergers produce a substantial amount of fast-moving ejecta, expanding outwardly for years after the merger. The interaction of these ejecta with the surrounding medium…
The origin of hotspots around Sgr A*: Orbital or pattern motion?
Tatsuya Matsumoto, Chi-Ho Chan, Tsvi Piran
The Gravity Collaboration detected a near-infrared hotspot moving around Sgr A* during the 2018 July 22 flare. They fitted the partial loop the hotspot made on the sky with a circu…
Linking extended and plateau emissions of short gamma-ray bursts
Tatsuya Matsumoto, Shigeo S. Kimura, Kohta Murase +1
Some short gamma-ray bursts (SGRBs) show a longer lasting emission phase, called extended emission (EE) lasting , as well as a plateau emission (PE) lasting $…
On short GRBs similar to GRB 170817A detected by Fermi GBM
Tatsuya Matsumoto, Tsvi Piran
von Kienlin et al. (2019) selected 11 short gamma-ray bursts (sGRBs) whose characteristics are similar to GRB 170817A. These bursts, like GRB 170817A, have a hard spike followed by…
Generalized compactness limit from an arbitrary viewing angle
Tatsuya Matsumoto, Ehud Nakar, Tsvi Piran
A -ray source must have a limited optical depth to pair production. This simple condition, called compactness, implies that gamma-ray bursts (GRBs) must involve a highly relativ…
Delayed jet breakouts from binary neutron star mergers
Tatsuya Matsumoto, Shigeo S. Kimura
Short gamma-ray bursts (sGRBs) are thought to be produced by binary NS mergers. While a sGRB requires a relativistic jet to break out of ejecta, the jet may be choked and fails to…
Polarization of the first-hour macronovae
Tatsuya Matsumoto
Macronovae (or kilonovae) are the optical and NIR counterparts of binary neutron star mergers. While the macronova in GW170817 was detected about 10 hours after the GW detection, f…
Constraints on the emitting region of the gamma-rays observed in GW170817
Tatsuya Matsumoto, Ehud Nakar, Tsvi Piran
The gravitational waves from the neutron star merger event GW170817 were accompanied by an unusually weak short GRB 170817A, by an optical/IR macronova/kilonova and by a long lasti…
Is the macronova in GW170817 powered by the central engine?
Tatsuya Matsumoto, Kunihito Ioka, Shota Kisaka +1
The gravitational wave event GW170817 from a binary neutron star (NS) merger is accompanied by electromagnetic counterparts, and the optical and near-infared emission is called a m…
Can Isolated Single Black Holes Produce X-ray Novae?
Tatsuya Matsumoto, Yuto Teraki, Kunihito Ioka
Almost all black holes (BHs) and BH candidates in our Galaxy have been discovered as soft X-ray transients, so-called X-ray novae. X-ray novae are usually considered to arise from…
GW150914-like Black Holes as Galactic High-Energy Sources
Kunihito Ioka, Tatsuya Matsumoto, Yuto Teraki +2
The first direct detections of gravitational waves (GWs) from black hole (BH) mergers, GW150914, GW151226 and LVT151012, give a robust lower limit on the number of mer…
Jet-powered supernovae of population III stars are observable by , , , and
Tatsuya Matsumoto, Daisuke Nakauchi, Kunihito Ioka +1
Supermassive black holes observed at high redshift could grow from direct collapse black holes (DCBHs) with mass , which result from the collapse o…
Can direct collapse black holes launch gamma-ray bursts and grow to supermassive black holes?
Tatsuya Matsumoto, Daisuke Nakauchi, Kunihito Ioka +2
The existence of black holes (BHs) of mass ~ 10^{9} M_sun at z > 6 is a big puzzle in astrophysics because even optimistic estimates of the accretion time are insufficient for stel…