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Evidence for two Lognormal States in Multi-wavelength Flux Variation of FSRQ PKS 1510-089

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 نشر من قبل Pankaj Kushwaha
 تاريخ النشر 2016
  مجال البحث فيزياء
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 تأليف Pankaj Kushwaha




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We present a systematic characterization of multi-wavelength emission from blazar PKS 1510-089 using well-sampled data at infrared(IR)-optical, X-ray and $gamma$-ray energies. The resulting flux distributions, except at X-rays, show two distinct lognormal profiles corresponding to a high and a low flux level. The dispersions exhibit energy dependent behavior except for the LAT $gamma$-ray and optical B-band. During the low level flux states, it is higher towards the peak of the spectral energy distribution, with $gamma$-ray being intrinsically more variable followed by IR and then optical, consistent with mainly being a result of varying bulk Lorentz factor. On the other hand, the dispersions during the high state are similar in all bands expect optical B-band, where thermal emission still dominates. The centers of distributions are a factor of $sim 4$ apart, consistent with anticipation from studies of extragalactic $gamma$-ray background with the high state showing a relatively harder mean spectral index compared to the low state.



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