English

Emitting electrons and source activity in Markarian 501

High Energy Astrophysical Phenomena 2015-06-05 v1

Abstract

We study the variation of the broad-band spectral energy distribution (SED) of the BL Lac object Mrk 501 as a function of source activity, from quiescent to flaring. Through chi-square-minimization we model eight simultaneous SED datasets with a one-zone Synchrotron-Self-Compton (SSC) model, and examine how model parameters vary with source activity. The emerging variability pattern of Mrk 501 is complex, with the Compton component arising from gamma-electron scatterings that sometimes are (mostly) Thomson and sometimes (mostly) extreme Klein-Nishina. This can be seen from the variation of the Compton to synchrotron peak distance according to source state. The underlying electron spectra are faint/soft in quiescent states and bright/hard in flaring states. A comparison with Mrk 421 suggests that the typical values of the SSC parameters are different in the two sources: however, in both jets the energy density is particle dominated in all states.

Keywords

Cite

@article{arxiv.1205.5237,
  title  = {Emitting electrons and source activity in Markarian 501},
  author = {Nijil Mankuzhiyil and Stefano Ansoldi and Massimo Persic and Elizabeth Rivers and Richard Rothschild and Fabrizio Tavecchio},
  journal= {arXiv preprint arXiv:1205.5237},
  year   = {2015}
}

Comments

8 pages, 4 figures, 1 table; accepted for publication in ApJ

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