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A Multi-wavelength Analysis of Binary-AGN Candidate PSO J334.2028+01.4075

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 Added by Adi Foord
 Publication date 2017
  fields Physics
and research's language is English




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We present analysis of the first Chandra observation of PSO J334.2028+01.4075 (PSO J334), targeted as a binary-AGN candidate based on periodic variations of the optical flux. With no prior targeted X-ray coverage for PSO J334, our new 40 ksec Chandra observation allows for the opportunity to differentiate between a single or binary-AGN system, and if a binary, can characterize the mode of accretion. Simulations show that the two expected accretion disk morphologies for binary-AGN systems are (i) a cavity, where the inner region of the accretion disk is mostly empty and emission is truncated blueward of the wavelength associated with the temperature of the innermost ring, or (ii) minidisks, where there is substantial accretion from the cirumbinary disk onto one or both of the members of the binary, each with their own shock-heated thin-disk accretion system. We find the X-ray emission to be well-fit with an absorbed power-law, incompatible with the simple cavity scenario. Further, we construct an SED of PSO J334 by combining radio through X-ray observations and find that the SED agrees well with that of a normal AGN, most likely incompatible with the minidisk scenario. Other analyses, such as locating the quasar on IR color-color diagrams and analyzing the quasar mass predicted by the fundamental plane of black hole activity, further highlight the similarity of PSO J334 with respect to normal AGN. On the multi-wavelength fronts we investigated, we find no evidence supporting PSO J334 as a binary-AGN system, though our analysis remains insensitive to some binary configurations.



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