Stochastic electron acceleration during the near-infrared and X-ray flares in Sagittarius A

Siming Liu, Fulvio Melia, Vahé Petrosian

Research output: Contribution to journalArticle

49 Scopus citations


Recent near-IR (NIR) and X-ray observations of Sagittarius A*'s spectrum have yielded several strong constraints on the transient energizing mechanism, justifying a reexamination of the stochastic acceleration model proposed previously for these events. We here demonstrate that the new results are fully consistent with the acceleration of electrons via the transit-time damping process. But more importantly, these new NIR and X-ray flares now can constrain the source size, the gas density, the magnetic field, and the wave energy density in the turbulent plasma. Future simultaneous multiwavelength observations with good spectral information will, in addition, allow us to study their temporal evolution, which will eventually lead to an accurate determination of the behavior of the plasma just minutes prior to its absorption by the black hole.

Original languageEnglish (US)
Pages (from-to)798-803
Number of pages6
JournalAstrophysical Journal
Issue number2 I
StatePublished - Jan 10 2006



  • Acceleration of particles
  • Black hole physics
  • Galaxy: center
  • Plasmas
  • Turbulence

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

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