The Mass of the Black Hole in the Quasar PG 2130+099

TL;DR

This study refines the black hole mass measurement in quasar PG 2130+099 using reverberation mapping, correcting previous inaccuracies caused by data sampling issues and secular variability, and confirms its consistency with established relationships.

Contribution

The paper provides a more accurate black hole mass estimate for PG 2130+099 through improved reverberation mapping analysis, addressing past measurement errors.

Findings

New lag measurement of 22.9 days for H-beta emission.

Black hole mass estimated at approximately 3.8 x 10^7 solar masses.

Revised measurements align PG 2130+099 with known R-L and MBH-Sigma relations.

Abstract

We present the results of a recent reverberation-mapping campaign undertaken to improve measurements of the radius of the broad line region and the central black hole mass of the quasar PG 2130+099. Cross correlation of the 5100 angstrom continuum and H-beta emission-line light curves yields a time lag of 22.9 (+4.4 - 4.3) days, corresponding to a central black hole mass MBH= 3.8 (+/- 1.5) x 10^7 Msun. This value supports the notion that previous measurements yielded an incorrect lag. We re-analyzed previous datasets to investigate the possible sources of the discrepancy and conclude that previous measurement errors were apparently caused by a combination of undersampling of the light curves and long-term secular changes in the H-beta emission-line equivalent width. With our new measurements, PG 2130+099 is no longer an outlier in either the R-L or the MBH-Sigma relationships.