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A multiwavelength temporal and spectral analysis of flares of 3C 279 during November 2017--July 2018 are presented in this work. Three bright gamma-ray flares were observed simultaneously in X-ray and Optical/UV along with a prolonged quiescent state. A harder-when-brighter trend is observed in both gamma-rays and X-rays during the flaring period. The gamma-ray light curve for all the flares are binned in one-day time bins and a day scale variability is observed. Variability time constrains the size and location of the emission region to 2.1$times$10$^{16}$ cm and 4.4$times$10$^{17}$ cm, respectively. The fractional variability reveals that the source is more than 100% variable in gamma-rays and it decreases towards the lower energy. A cross-correlation study of the emission from different wavebands is done using the textit{DCF} method, which shows a strong correlation between them without any time lags. The zero time lag between different wavebands suggest their co-spatial origin. This is the first time 3C 279 has shown a strong correlation between gamma-rays and X-rays emission with zero time lag. A single zone emission model was adopted to model the multiwavelength SEDs by using the publicly available code GAMERA. The study reveals that a higher jet power in electrons is required to explain the gamma-ray flux during the flaring state, as much as, ten times of that required for the quiescent state. However, more jet power in magnetic field has been observed during the quiescent state compared to the flaring state.
The Flat Spectrum Radio Quasar 3C 279 has been very active since a few years with multiple flaring events occurring at high energies. As part of the H.E.S.S. Target of Opportunity program, 3C 279 was observed multiple times in 2017 and 2018 following
Long-term 17.6~GHz radio monitoring of the broad absorption line quasar, Mrk,231, detected a strong flare in late 2017. This triggered four epochs of Very Long Baseline Array (VLBA) observations from 8.4~GHz to 43~GHz over a 10-week period as well as
In this work, I have presented a multi-frequency variability and correlation study of the blazar Ton 599, which was observed first time in flaring state at the end of 2017. Data from textit{Fermi}-LAT, Swift-XRT/UVOT, Steward Observatory, and OVRO (1
We have monitored the flat spectrum radio quasar, 3C 279, in the optical $B$, $V$, $R$ and $I$ passbands from 2018 February to 2018 July for 24 nights, with a total of 716 frames, to study flux, colour and spectral variability on diverse timescales.
The flat spectrum radio quasar 3C 279 is a known $gamma$-ray variable source that has recently exhibited minute-scale variability at energies $>100$ MeV. One-zone leptonic models for blazar emission are severely constrained by the short timescale var