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arXiv · 2110.02055

Changing look AGN Mrk 590: Broad line region and black hole mass from photometric reverberation mapping

Amit Kumar Mandal·Malte Schramm·Suvendu Rakshit·C. S. Stalin·Bovornpratch Vijarnwannaluk·Wiphu Rujopakarn·Saran Poshyachinda·Vladimir V. Kouprianov·Joshua B. Haislip·Daniel E. Reichart·Ram Sagar·Blesson Mathew
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Abstract

We present the results of photometric reverberation mapping observations on the changing look active galactic nucleus Mrk 590 at z = 0.026. The observations were carried out from July to December, 2018 using broad band B, R and narrow band H{\alpha} and S II filters. B-band traces the continuum emission from the accretion disk, R-band encompasses both the continuum emission from the accretion disk and the redshifted H{\alpha} line from the broad line region (BLR), S II band contains the redshifted H{\alpha} emission and the H{\alpha} band traces the continuum emission underneath the S II band. All the light curves showed strong variation with a fractional root-mean-square variation of 0.132 (+/-) 0.001 in B-band and 0.321 (+/-) 0.001 in H{\alpha} line. From cross-correlation function analysis, we obtained a delayed response of H{\alpha} line emission to the optical B-band continuum emission of 21.44(+1.49/-2.11) days in the rest-frame of the source, corresponding to a linear size of the BLR of 0.018 pc. This is consistent with previous estimates using H{\beta}. By combining the BLR size with the H{\alpha} line full width at half maximum of 6478 (+/-) 240 km/s measured from a single-epoch spectrum obtained with the Subaru telescope, we derived a black hole mass of 1.96 (+0.15 / -0.21) X 10^8 Msun.

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Amit Kumar Mandal, Malte Schramm, Suvendu Rakshit, C. S. Stalin, Bovornpratch Vijarnwannaluk, Wiphu Rujopakarn, Saran Poshyachinda, Vladimir V. Kouprianov, Joshua B. Haislip, Daniel E. Reichart, Ram Sagar, Blesson Mathew. 2021-10-05. Changing look AGN Mrk 590: Broad line region and black hole mass from photometric reverberation mapping. https://doi.org/10.1093/mnras%2Fstab2909

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