Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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LONG-TERM SOFT X-RAY VARIABILITY OF ACTIVE GALAXY MRK 841

  • Kim, Chul-Hee (Division of Earth Science Education and Institute of Science Education, Chonbuk National University)
  • Published : 2008.04.30
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Abstract

We present an analysis of the soft X-ray emission of MRK 841 to investigate its long-term variation. The light variation of MRK 841 for three different energy bands of soft, medium, and hard values were studied. The maximum variability with a factor of 5 for about two years was confirmed at all three different bands. The light curves exhibit a gradual variation of brightness. In addition to a gradual variation, the short- term or micro variation was also confirmed with a factor of about two for all three different bands. The light variation of each band did not exhibit a correlation between them, but the flare event is strongest in the soft band. The hardness ratio for hard and soft bands shows irregular variation but there was no correlation between them. It was confirmed that there is a gradual decrease of the photon index. Results of our analysis are discussed within the framework of the accretion disk phenomenon.

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References

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