Connecting Theory to Observations

13-15 November 2023
Flatiron Institute, New York, USA

Black holes of all sizes demonstrate enigmatic flaring activity. Stellar-mass black holes show puzzling short time-scale variability, from optical to X-ray bands, and are notorious for their unexplained state transitions during outbursts. Supermassive black holes, on the other hand, can erupt in intense flares visible up to TeV energies. Thanks to their extreme nature, these flares offer a unique view into the functionality of the accretion flows around black holes.

This 2.5-day workshop brought together high-energy observers and plasma astrophysicists to discuss the latest observations and the most promising plasma energization theories for the flares. The main goals of the workshop were to 1) establish a common language between the communities and 2) lay out a future roadmap for the next crucial steps needed to advance our understanding of the black hole flaring phenomena. These goals were supported by providing ample discussion time and focusing on long review talks covering the state-of-the-art of both fields.


List of talks

Alexandra VeledinaVariability in X-ray black hole binaries and its connection to accretion geometry
Qi FengTeV Gamma-Ray Variability in Blazars & more
Lorenzo SironiParticle acceleration in BH jets and coronae
Dmitri UzdenskyPlasma physics of accretion flows
PhilippovKinetic view into the BH magnetospheres
Joonas NättiläRadiation from magnetized plasmas
Andy FabianX-ray Spectroscopy of Luminous Black Holes
Manel ErrandoX-ray polarization observations (IXPE)
Kun HuIXPE observations of blazars and stellar mass black holes
Vladislav LotkevPolarimetric Analysis of Black Hole X-ray Binaries
Frank RiegerVHE Flares in Blazars and Radio Galaxies
Hayk HakobyanTeV Flaring of M87* powered by magnetic reconnection
Janeth ValverdeGeV Flare Characteristic in Blazars
Amelia HanklaKinetic and Two-Temperature Plasma Physics of Black Hole X-ray Coronae
Jordy DavelaarSagittarius A* as a testing laboratory
Kohta MuraseHigh-Energy Neutrinos from Supermassive Black Holes
Aharonian, Coppi, MukherjeeBlazar Flares in the γ-ray Band

List of participants

  • Alexandra Veledina
  • Andy Fabian
  • Ari Brill
  • Dmitri Uzdensky
  • Fabrizio Tavecchio
  • Felix Aharonian
  • Frank Rieger
  • Hayk Hakobyan
  • Joonas Nättilä
  • Jordy Davelaar
  • Kohta Murase
  • Kun Hu
  • Lorenzo Sironi
  • Manel Errando
  • Paolo Coppi
  • Qi Feng
  • Reshmi Mukherjee
  • Samar Sari-Harb
  • Sasha Philippov
  • Yuri Levin

CDY Workshop Organizing Committee 

  • Felix Aharonian
  • Paolo Coppi
  • Yuri Levin
  • Reshmi Mukherjee
  • Joonas Nättilä
  • Jordy Davelaar