Simultaneous optical monitoring of BL Lacertae object S5 0716+714 with high temporal resolution

Abstract

We have monitored the BL Lacertae object S5 0716+714 simultaneously in the B, R and I bands on three nights in November 2014. The average time resolution is quite high (73s, 34s, 58s for the filters B, R and I), which can help us trace the profile of the variation and search for the short inter-band time delay. Intra-day variability was about 0.1 mag on the first two nights and more than 0.3 mag on the third. A bluer-when-brighter color behavior was found. An clear loop path can be seen on the color-magnitude diagram of the third night, revealing possible time delays between variations at high and low energies. It is the first time that the intra-day spectral hysteresis loop has been found so obviously in the optical band. We used the interpolated cross-correlation function method to further confirm the time delay and calculated the values of lag between light curves at different wavelengths on each night. On the third night, variations in the R and B bands is approximately 1.5 minutes lagging behind the I band. Such optical time delay is probably due to the interplay of different processes of electrons in the jet of the blazar.

7 pages, 5 figures, accepted by MNRAS

References in corpus (12)

• Multi-colour optical monitoring of eight red blazars
• Periodic Oscillations in the Intra-day Optical Light Curves of the Blazar S5 0716+714
• Multifrequency monitoring of the blazar 0716+714 during the GASP-WEBT-AGILE campaign of 2007
• Multi-wavelength variability properties of Fermi blazar S5 0716+714
• Multi-color Near Infra-red Intra-day and Short Term Variability of the Blazar S5 0716+714
• Rapid optical variability in blazar S5 0716+71 during 2010 March
• Disentangling the synchrotron and Inverse Compton variability in the X-ray emission of the intermediate BL Lac object S5 0716+71
• AGILE and Swift simultaneous observations of the blazar S50716+714 during the bright flare of October 2007
• Anti-correlated Optical Flux and Polarization Variability in BL Lac
• Intra-day variability observations of S5 0716+714 over 4.5 years at 4.8 GHz
• Differential Density Statistics of Galaxy Distribution and the Luminosity Function
• Six-year Optical Monitoring of BL Lacertae Object 1ES 0806+52.4

Cited by in corpus (11)

• Multi-band optical variability of 3C 279 on diverse timescales
• Optical monitoring of BL Lac object S5 0716+714 and FSRQ 3C273 from 2000 to 2014
• Multi-color optical monitoring of the BL Lacertae object S5 0716+714 during the 2012 outburst
• Search for Intra-day Optical Variability in $\gamma$-ray--loud Blazars S5 0716+714 and 3C 273
• Radio and optical intra-day variability observations of five blazars
• Extremely rapid x-ray flares of tev blazars in the rxte era
• Intra-day optical multi-band quasi-simultaneous observation of BL Lacertae object S5 0716+714 from 2013 to 2016
• Optical variability in IBL S5 0716+714 during the 2013-2015 outburst
• Optical Spectral Variations of a Large Sample of Fermi Blazars
• Optical monitoring in southern blazars. Analysis of variability and spectral colour behaviours
• The intra-day Optical Monitoring of BL Lacerate Object 1ES 1218+304 at Its Highest X-ray Flux Level