The Lick AGN Monitoring Project: Photometric Light Curves and Optical Variability Characteristics

TL;DR

This study presents optical photometric light curves of 13 Seyfert 1 galaxies, analyzing their variability and assessing the feasibility of reverberation mapping for black hole mass measurements.

Contribution

It provides well-sampled optical light curves and variability analysis for a sample of nearby Seyfert galaxies, aiding in black hole mass estimation through reverberation mapping.

Findings

No significant lag detected between B- and V-band variations.

No notable color variations observed in the AGN sample.

Light curves enable variability characterization over several months.

Abstract

The Lick AGN Monitoring Project targeted 13 nearby Seyfert 1 galaxies with the intent of measuring the masses of their central black holes using reverberation mapping. The sample includes 12 galaxies selected to have black holes with masses roughly in the range 10^6-10^7 solar masses, as well as the well-studied AGN NGC 5548. In conjunction with a spectroscopic monitoring campaign, we obtained broad-band B and V images on most nights from 2008 February through 2008 May. The imaging observations were carried out by four telescopes: the 0.76-m Katzman Automatic Imaging Telescope (KAIT), the 2-m Multicolor Active Galactic Nuclei Monitoring (MAGNUM) telescope, the Palomar 60-in (1.5-m) telescope, and the 0.80-m Tenagra II telescope. Having well-sampled light curves over the course of a few months is useful for obtaining the broad-line reverberation lag and black hole mass, and also allows us to examine the characteristics of the continuum variability. In this paper, we discuss the observational methods and the photometric measurements, and present the AGN continuum light curves. We measure various variability characteristics of each of the light curves. We do not detect any evidence for a time lag between the B- and V-band variations, and we do not find significant color variations for the AGNs in our sample.