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arXiv · 1706.07183

Intraday Optical Variability of BL Lacertae

Nankun Meng·Jianghua Wu·James R. Webb·Xiaoyuan Zhang·Yan Dai
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Abstract

We monitored BL Lacertae simultaneously in the optical B, V, R and I bands for 13 nights during the period 2012-2016. The variations were well correlated in all bands and the source showed significant intraday variability (IDV). We also studied its optical flux and colour behaviour, and searched for inter-band time lags. A strong bluer-when-brighter chromatism was found on the intra-night time-scale. The spectral changes are not sensitive to the host galaxy contribution. Cross-correlation analysis revealed possible time delay of about 10 min between variations in the V and R bands. We interpreted the observed flares in terms of the model consisting of individual synchrotron pulses.

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Nankun Meng, Jianghua Wu, James R. Webb, Xiaoyuan Zhang, Yan Dai. 2017-06-22. Intraday Optical Variability of BL Lacertae. https://doi.org/10.1093/mnras%2Fstx1055

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