Participants

Postdocs:

Kenta Hotokezaka  Chi-Ho (Edwin) Chan  Daniel Kagan

Tatsuya Matsumoto Noemi Globus 

Tamar Faran Gilad Svirski   Matteo Pais     Xiaping Tang

Students:

Ron Mor Barel Skuratovski Dekel Saban Odelia Teboul
 

Collaborators:

 Ehud Nakar Julian Krolik Yuri Lyubarski      Zhenya Derishev Taeho Rtu

Projects

Gamma Ray Burst

Gamma Ray Bursts are the brightest explosions in the Universe. The  research spans numerous aspects of this events, ranging from the origin to their effects on Life on Earth. 

For more information see a popular reviews (PDF link): The Brightest Explosions in the Universe! 

Reviews of Modern Physics.

The Rate and luminosity function of GRBs.

 

Kagan D., Nakar E., Piran T.,Physics of the saturation of particle acceleration in relativistic magnetic reconnection, 2018,MNRAS, 476,3902

Granot J., Piran T., Bromberg O., Racusin J. L., Daigne F.,Gamma-Ray Bursts as Sources of Strong Magnetic Fields, 2018,smfu.book, 54,481

Moharana R., Piran T.,Observational evidence for mass ejection accompanying short gamma-ray bursts, 2017,MNRAS, 472,L55

Derishev E., Piran T.,The Physical Conditions of the Afterglow Implied by MAGIC’s Sub-TeV Observations of GRB 190114C, 2019,ApJL, 880,L27

Derishev E., Piran T.,GRB Afterglow Parameters in the Era of TeV Observations: The Case of GRB 190114C, 2021,ApJ, 923,135

Piran T.,GRBs' Rosseta stone - the sub-TeV emission observed in GRB 190114c (INVITED), 2021,heas.conf,19

Piran T., Nakar E., Mazzali P., Pian E.,Relativistic Jets in Core-collapse Supernovae, 2019,ApJL, 871,L25

Irwin C. M., Nakar E., Piran T.,The propagation of choked jet outflows in power-law external media, 2019,MNRAS, 489,2844

Nakar E., Piran T.,The Observable Signatures of GRB Cocoons, 2017,ApJ, 834,28

Irwin C. M., Linial I., Nakar E., Piran T., Sari R., Bolometric light curves of aspherical shock breakout, 2021,MNRAS, 508,5766

Irwin C. M., Tang X., Piran T., Nakar E.,Jet-driven bubbles in Fanaroff-Riley type-I sources, 2019,MNRAS, 488,4926

Yamasaki S., Piran T., Analytic modelling of synchrotron self-Compton spectra: Application to GRB 190114C, 2022,MNRAS, 512,2142

Leiderschneider E., Piran T.,Gravitational radiation from accelerating jets, 2021,PhRvD, 104,104002

Piran T.,Jet Gravitational Waves, 2022,  arXiv:2210.02740

 

Tidal Disruption Events

TDEs – Tidal Disruption Events take place when a star that passes near a massive black hole at a Galactic center is thorn apart and disrupted. 

Jerusalem TDE Workshop-Link

 

Ryu T., Krolik J., Piran T., Noble S. C.,Tidal Disruptions of Main-sequence Stars. I. Observable Quantities and Their Dependence on Stellar and Black Hole Mass, 2020,ApJ, 904,98

Ryu T., Krolik J., Piran T., Noble S. C.,Tidal Disruptions of Main-sequence Stars. II. Simulation Methodology and Stellar Mass Dependence of the Character of Full Tidal Disruptions, 2020,ApJ, 904,99

Ryu T., Krolik J., Piran T., Noble S. C.,Tidal Disruptions of Main-sequence Stars. III. Stellar Mass Dependence of the Character of Partial Disruptions, 2020,ApJ, 904,100

Ryu T., Krolik J., Piran T., Noble S. C.,Tidal Disruptions of Main-sequence Stars. IV. Relativistic Effects and Dependence on Black Hole Mass, 2020,ApJ, 904,101

Krolik J., Piran T., Ryu T.,Tidal Disruptions of Main-sequence Stars. V. The Varieties of Disruptions, 2020,ApJ, 904,68

Chan C.-H., Piran T., Krolik J. H., Saban D.,Tidal Disruption Events in Active Galactic Nuclei, 2019,ApJ, 881,113

Chan C.-H., Piran T., Krolik J. H.,Light Curves of Tidal Disruption Events in Active Galactic Nuclei, 2020,ApJ, 903,17

Chan C.-H., Piran T., Krolik J. H., High-energy Emission from Tidal Disruption Events in Active Galactic Nuclei, 2021,ApJ, 914,107

Matsumoto T., Piran T.,Generalized equipartition method from an arbitrary viewing angle, 2022, ,arXiv:2211.10051

Ryu T., Krolik J., Piran T., Extremely Relativistic Tidal Disruption Events, 2022,arXiv,arXiv:2211.00059

Matsumoto T., Piran T., Krolik J. H.,What powers the radio emission in TDE AT2019dsg: A long-lived jet or the disruption itself?, 2022,MNRAS, 511,5085

Matsumoto T., Piran T.,Radio constraint on outflows from tidal disruption events, 2021,MNRAS, 507,4196

Ryu T., Krolik J., Piran T.,Measuring Stellar and Black Hole Masses of Tidal Disruption Events, 2020,ApJ, 904,73

Matsumoto T., Piran T., Limits on mass outflow from optical tidal disruption events, 2021,MNRAS, 502,3385

Roth N., Rossi E. M., Krolik J., Piran T., Mockler B., Kasen D.,Radiative Emission Mechanisms, 2020,SSRv, 216,114

Yalinewich A., Steinberg E., Piran T., Krolik J. H.,Radio emission from the unbound debris of tidal disruption events, 2019,MNRAS, 487,4083

Svirski G., Piran T., Krolik J.,Elliptical Accretion and Low Luminosity from High Accretion Rate Stellar Tidal Disruption Events, 2017,MNRAS, 467,1426

Chan C.-H., Krolik J. H., Piran T.,Magnetorotational Instability in Eccentric Disks, 2018,ApJ, 856,12

Ryu T., Krolik J., Piran T., The Impact of Shocks on the Vertical Structure of Eccentric Disks, 2021,ApJ, 920,130

Chan C.-H., Piran T., Krolik J. H.,Nonlinear Evolution of the Magnetorotational Instability in Eccentric Disks, 2022,ApJ, 933,81

 

Binary Neutron Star Mergers

Mergers between binary neutron stars are prime candidates sources for gravitational wave that is searched for by advanced detectors like LIGO and Virgo. They are also, as I have predicted in 1989 the sources of short Gamma-Ray Bursts and the sites where heavy elements are synthesized. 

Colliding Neutron Stars as the Source of Heavy Elements-Link, PDF

 

Abbott B. P., Abbott R., Abbott T. D., et al.,Multi-messenger Observations of a Binary Neutron Star Merger, 2017,ApJL, 848,L12

Arcavi I., Howell D. A., McCully C., et al., LIGO/Virgo G298048: Las Cumbres Observatory Detection of The Possible Optical Counterpart in NGC 4993, 2017,GCN, 21538,1

Arcavi I., McCully C., Hosseinzadeh G., et al.,Optical Follow-up of Gravitational-wave Events with Las Cumbres Observatory, 2017,ApJL, 848,L33

Hallinan G., Corsi A., Mooley K. P., et al.,A radio counterpart to a neutron star merger, 2017,Sci, 358,1579

Kasliwal M. M., Nakar E., Singer L. P., et al.,Illuminating gravitational waves: A concordant picture of photons from a neutron star merger, 2017,Sci, 358,1559

Pian E., D'Avanzo P., Benetti S., et al.,Spectroscopic identification of r-process nucleosynthesis in a double neutron-star merger, 2017,Natur, 551,67

Mooley K. P., Nakar E., Hotokezaka K., et al.,A mildly relativistic wide-angle outflow in the neutron-star merger event GW170817, 2018,Natur, 554,207

Nakar E., Piran T.,Implications of the radio and X-ray emission that followed GW170817, 2018,MNRAS, 478,407

Gottlieb O., Nakar E., Piran T., Hotokezaka K.,A cocoon shock breakout as the origin of the γ-ray emission in GW170817, 2018,MNRAS, 479,588

Nakar E., Piran T.,Implications of the radio and X-ray emission that followed GW170817, 2018,MNRAS, 478,407

Hotokezaka K., Kiuchi K., Shibata M., Nakar E., Piran T.,Synchrotron Radiation from the Fast Tail of Dynamical Ejecta of Neutron Star Mergers, 2018,ApJ, 867,95

Nakar E., Gottlieb O., Piran T., Kasliwal M. M., Hallinan G.,From γ to Radio: The Electromagnetic Counterpart of GW170817, 2018,ApJ, 867,18

Gottlieb O., Nakar E., Piran T., Hotokezaka K.,A cocoon shock breakout as the origin of the γ-ray emission in GW170817, 2018,MNRAS, 479,588

Bromberg O., Tchekhovskoy A., Gottlieb O., Nakar E., Piran T.,The γ-rays that accompanied GW170817 and the observational signature of a magnetic jet breaking out of NS merger ejecta, 2018,MNRAS, 475,2971

Gottlieb O., Nakar E., Piran T.,The cocoon emission - an electromagnetic counterpart to gravitational waves from neutron star mergers, 2018,MNRAS, 473,576

Gottlieb O., Nakar E., Piran T.,Detectability of neutron star merger afterglows, 2019,MNRAS, 488,2405

Matsumoto T., Nakar E., Piran T., Generalized compactness limit from an arbitrary viewing angle, 2019,MNRAS, 486,1563

Matsumoto T., Nakar E., Piran T., Constraints on the emitting region of the gamma-rays observed in GW170817, 2019,MNRAS, 483,1247

Pais M., Piran T., Lyubarsky Y., Kiuchi K., Shibata M.,The collimation of relativistic jets in post-neutron star binary merger simulations, 2022,arXiv,arXiv:2211.09135

Ricci R., Troja E., Bruni G., et al.,Searching for the radio remnants of short-duration gamma-ray bursts, 2021,MNRAS, 500,1708

Bruni G., O'Connor B., Matsumoto T., Troja E., Piran T., Piro L., Ricci R.,Late-time radio observations of the short GRB 200522A: constraints on the magnetar model, 2021,MNRAS, 505,L41

Troja E., O'Connor B., Ryan G., et al., Accurate flux calibration of GW170817: is the X-ray counterpart on the rise?, 2022,MNRAS, 510,1902 

Nakar E., Piran T., Afterglow Constraints on the Viewing Angle of Binary Neutron Star Mergers and Determination of the Hubble Constant, 2021,ApJ, 909,114

Margalit B., Piran T.,Shock within a shock: revisiting the radio flares of NS merger ejecta and gamma-ray burst-supernovae, 2020,MNRAS, 495,4981

Matsumoto T., Piran T.,On short GRBs similar to GRB 170817A detected by Fermi-GBM, 2020,MNRAS, 492,4283

 

Nucleosynthesis and the origin of heavy (r-process) elements in the Universe

I have proposed that these elements (like gold) have been produced in collisions between neutron stars.  Recent observations of macronova that followed GW 170817 support these ideas 

 

Hotokezaka K., Sari R., Piran T.,Analytic heating rate of neutron star merger ejecta derived from Fermi's theory of beta decay, 2017,MNRAS, 468,91

Beniamini P., Piran T.,The Gravitational waves merger time distribution of binary neutron star systems, 2019,MNRAS, 487,4847

Hotokezaka K., Beniamini P., Piran T.,Neutron star mergers as sites of r-process nucleosynthesis and short gamma-ray bursts, 2018,IJMPD, 27,1842005

 

 Black Holes

Link: 
The inner Structure of Black Holes - Can Black Holes be Portals to Other Universes

 

Hotokezaka K., Piran T.,Implications of the Low Binary Black Hole Aligned Spins Observed by LIGO, 2017,ApJ, 842,111

Piran Z., Piran T.,The Origin of Binary Black Hole Mergers, 2020,ApJ, 892,64

Piran T., Hotokezaka K.,Who Ordered That? On The Origin of LIGO's Merging Binary Black Holes, 2018,arXiv,arXiv:1807.01336

Yamaguchi M. S., Kawanaka N., Bulik T., Piran T.,Detecting Black Hole Binaries by Gaia, 2018,ApJ, 861,21

 

Ultra High Energy Cosmic Ray

Ultra High Energy Cosmic Rays (UHECRs) and the most energetic particles that reach Earth from outer space. My research involves models for their origin and their composition.  Read moreabout Ultra High Energy Cosmic Rays

 

Globus N., Piran T., Hoffman Y., Carlesi E., Pomarède D.,Cosmic ray anisotropy from large-scale structure and the effect of magnetic horizons, 2019,MNRAS, 484,4167

Tang X., Piran T.,Positron flux and γ-ray emission from Geminga pulsar and pulsar wind nebula, 2019,MNRAS, 484,3491

Globus N., Piran T.,The Extragalactic Ultra-high-energy Cosmic-Ray Dipole, 2017,ApJL, 850,L25

Globus N., Allard D., Parizot E., Piran T.,Probing the Extragalactic Cosmic Rays Origin with Gamma-Ray and Neutrino Backgrounds, 2017,ICRC, 301,516

Globus N., Allard D., Parizot E., Lachaud C., Piran T.,Can we reconcile the TA excess and hotspot with Auger observations?, 2017,ICRC, 301,493

Globus N., Allard D., Parizot E., Piran T.,Probing the Extragalactic Cosmic-Ray Origin with Gamma-Ray and Neutrino Backgrounds, 2017,ApJL, 839,L22

Benyamin D., Shaviv N. J., Piran T.,Electron-capture Isotopes Could Constrain Cosmic-Ray Propagation Models, 2017,ApJ, 851,109

Nava L., Benyamin D., Piran T., Shaviv N. J.,Reconciling the diffuse Galactic γ-ray and the cosmic ray spectra, 2017,MNRAS, 466,3674

 

Other Relativistic Transients

1.Matsumoto T., Chan C.-H., Piran T.,The origin of hotspots around Sgr A*: orbital or pattern motion?, 2020,MNRAS, 497,2385