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The Multi-wavelength Characteristics of the TeV Binary LS I +61$^circ$ 303

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 نشر من قبل Lab Saha
 تاريخ النشر 2016
  مجال البحث فيزياء
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We study the characteristics of the TeV binary LS I +61$^circ$ 303 in radio, soft X-ray, hard X-ray, and gamma-ray (GeV and TeV) energies. The long term variability characteristics are examined as a function of the phase of the binary period of 26.496 days as well as the phase of the super orbital period of 1626 days, dividing the observations into a matrix of 10$times$10 phases of these two periods. It is found that the long term variability can be described by a sine function of the super orbital period, with the phase and amplitude systematically varying with the binary period phase. We also find a definite wavelength dependent change in this variability description. To understand the radiation mechanism, we define three states in the orbital/ super orbital phase matrix and examine the wide band spectral energy distribution. The derived source parameters indicate that the emission geometry is dominated by a jet structure showing a systematic variation with the orbital/ super orbital period. We suggest that LS I +61$^circ$ 303 is likely to be a micro-quasar with a steady jet.



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