Astrophysical Black Holes: A Rapidly Moving Field

Session

Relativistic jets and particle acceleration

25 Jun 2023, 09:30

University of Hong Kong, Centennial Campus, CPD 3.04

60. Looking for Physics in the Weather: 30 Years of Gamma-Ray Blazar Observations

Prof. Paolo Coppi (Yale University)

25/06/2023, 09:30

Talk

The launch of the Compton Gamma-Ray Observatory in 1991 revealed that the powerful relativistic outflows (“jets”) produced by accreting supermassive black holes are in fact some of the most prodigious emitters of gamma-rays in the Universe. Even accounting for likely relativistic beaming and boosting effects, this gamma-ray emission can represent a significant of the black hole’s accretion...

69. The Observation of the Brightest GRB 221009A by LHAASO

Prof. Zhen Cao

25/06/2023, 10:05

Talk

LHAASO observed GRB221009A, as the brightest GRB, with it nearly in the middle of the FoV. The onset of the afterglow in TeV band was first time observed by measuring the flux from the GRB since T0 set by a precursor. This enables 1) Determining the start time of the afterglow T* $\sim 226$ s after T0; 2) Setting the most strict limit on the prompt emission in TeV band $\sim10^{-5}$; 3)...

70. Black holes as cosmic accelerators

Dr Noemie Globus

25/06/2023, 11:10

Talk

The origin of ultra high energy cosmic rays remains a mystery. It represents the challenge of finding the nature of the most powerful particle accelerators in the Universe, which exhibit collisions with center of mass energies about 100 times those attainable at the LHC. During their acceleration process, they produce high energy gamma-rays and neutrinos. These secondary messengers reveal...

24. Particle acceleration in AGN jets

Dr Jieshuang Wang

25/06/2023, 11:45

Talk

Jets of active galactic nuclei are observed from less than parsec scale to mega-parsec scale. They are powerful particle accelerators shining across the electromagnetic spectrum. In this talk, (1) I’ll mainly present our analytical and numerical works on shear acceleration. Recent observations indicate a synchrotron origin of X-ray emission in kpc-scale, which requires in-situ acceleration of...

33. Extreme particle acceleration at AGN jet termination shocks

Prof. Gwenael Giacinti (Tsung-Dao Lee Institute & Shanghai Jiao Tong University)

25/06/2023, 12:03

Talk

Extragalactic plasma jets are some of the few astrophysical environments able to confine ultra-high energy cosmic rays, but whether they are capable of accelerating these particles is unknown. In this work, we revisit particle acceleration at relativistic magnetized shocks beyond the local uniform field approximation, by considering the global transverse structure of the jet. Using large...