Seven-Year Multi-Color Optical Monitoring of BL Lacertae Object S5 0716+714

TL;DR

This paper presents a comprehensive seven-year optical monitoring of the BL Lac object S5 0716+714, revealing frequent variability, significant brightness changes, and color-magnitude correlations across multiple optical bands.

Contribution

It provides one of the largest optical datasets for this object, offering detailed insights into its variability and spectral behavior over multiple timescales.

Findings

Frequent intraday variability observed.

Object varied by 2.614 magnitudes in the i band.

Strong bluer-when-brighter chromatism detected.

Abstract

We have monitored the BL Lac object S5 0716+714 in five intermediate optical wavebands from 2004 September to 2011 April. Here we present the data that include 8661 measurements which represents one of the largest databases obtained for an object at optical domain. A simple analysis of the data indicates that the object was active in most time, and intraday variability was frequently observed. In total, the object varied by 2.614 magnitudes in the $i$ band. Strong bluer-when-brighter chromatism was observed on long, intermediate, and short timescales.