2015/12/28 by Dingrong Xiong, Xiong Zhang, Tingfeng Yi +5 · 1 citation
Physics and Astronomy · #Amplitude #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #BL Lac object #Duty cycle #Flux (metallurgy) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Lag #astro-ph.HE
paper · pdf · doi:10.3847/0067-0049/222/2/24
55 pages, 11 figures, 7 tables, accepted for publication in ApJS
arxiv created 2015/12/28 · openalex publication_date 2016/02/01 · arxiv updated 2016/03/23 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
ABSTRACT We have monitored the BL Lac object Mrk 501 in the optical V , R , and I bands from 2010 to 2015. For Mrk 501, the presence of a strong host galaxy component can affect the results of photometry. After subtracting the host galaxy contributions, the source shows intraday and long-term variabilities for optical flux and color indices. The average variability amplitudes of the V , R , and I bands are , respectively, and the value of the duty cycle is 14.87%. A minimal variability timescale of 106 minutes is detected. No significant time lag between the V and I bands is found on one night. The bluer-when-brighter (BWB) trend is dominant for Mrk 501 on intermediate, short, and intraday timescales, which supports the shock-in-jet model. For the long timescale, Mrk 501, in different states, can have different BWB trends. The corresponding results for non-correcting host galaxy contributions are also presented.