Stability of the Broadline Region Geometry and Dynamics in Arp 151 Over Seven Years
Abstract
The Seyfert 1 galaxy Arp 151 was monitored as part of three reverberation mapping campaigns spanning 20082015. We present modeling of these velocityresolved reverberation mapping data sets using a geometric and dynamical model for the broadline region (BLR). By modeling each of the three data sets independently, we infer the evolution of the BLR structure in Arp 151 over a total of 7 yr and constrain the systematic uncertainties in nonvarying parameters such as the black hole mass. We find that the BLR geometry of a thick disk viewed close to faceon is stable over this time, although the size of the BLR grows by a factor of ̃2. The dynamics of the BLR are dominated by inflow, and the inferred black hole mass is consistent for the three data sets, despite the increase in BLR size. Combining the inference for the three data sets yields a black hole mass and statistical uncertainty of log_{10}({M}_{BH}}/{M}_{☉ }) = {6.82}_{0.09}^{+0.09} with a standard deviation in individual measurements of 0.13 dex.
 Publication:

The Astrophysical Journal
 Pub Date:
 April 2018
 DOI:
 10.3847/15384357/aab3c6
 arXiv:
 arXiv:1803.02318
 Bibcode:
 2018ApJ...856..108P
 Keywords:

 galaxies: active;
 galaxies: individual: Arp 151;
 galaxies: nuclei;
 methods: statistical;
 Astrophysics  Astrophysics of Galaxies
 EPrint:
 21 pages, 8 figures, 2 tables. Accepted for publication in ApJ