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Title: MAXI INVESTIGATION INTO THE LONG-TERM X-RAY VARIABILITY FROM THE VERY-HIGH-ENERGY γ-RAY BLAZAR Mrk 421

The archetypical very-high-energy γ-ray blazar Mrk 421 was monitored for more than three years with the Gas Slit Camera on board Monitor of All Sky X-ray Image (MAXI), and its long-term X-ray variability was investigated. The MAXI light curve in the 3-10 keV range was transformed into the periodogram in the frequency range f = 1 × 10{sup –8}-2 × 10{sup –6} Hz. The artifacts on the periodogram, resulting from data gaps in the observed light curve, were extensively simulated for variations with a power-law-like power spectrum density (PSD). By comparing the observed and simulated periodograms, the PSD index was evaluated as α = 1.60 ± 0.25. This index is smaller than that obtained in the higher-frequency range (f ≳ 1 × 10{sup –5} Hz), namely, α = 2.14 ± 0.06 in the 1998 ASCA observation of the object. The MAXI data impose a lower limit on the PSD break at f {sub b} = 5 × 10{sup –6} Hz, consistent with the break of f {sub b} = 9.5 × 10{sup –6} Hz suggested from the ASCA data. The low-frequency PSD index of Mrk 421 derived with MAXI falls well within the range of typical values among nearby Seyfertmore » galaxies (α = 1-2). The physical implications from these results are briefly discussed.« less
Authors:
 [1] ; ; ; ; ;  [2] ; ;  [3] ; ; ;  [4] ;  [5]
  1. Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA) 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)
  2. Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)
  3. ISS Science Project Office, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505 (Japan)
  4. MAXI team, Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)
  5. Department of Physics, Nihon University, 1-8-14 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan)
Publication Date:
OSTI Identifier:
22364749
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 798; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BL LACERTAE OBJECTS; BLACK HOLES; CAMERAS; COMPARATIVE EVALUATIONS; DIAGRAMS; IMAGES; INDEXES; QUASARS; SEYFERT GALAXIES; VARIATIONS; VISIBLE RADIATION; X RADIATION; X-RAY GALAXIES