dc.contributor.author |
Gulati, Sanna |
|
dc.contributor.author |
Bhattacharya, Debbijoy |
|
dc.contributor.author |
Bhattacharyya, Subir |
|
dc.contributor.author |
Bhatt, N |
|
dc.contributor.author |
Stalin, C. S |
|
dc.contributor.author |
Agrawal, V. K |
|
dc.date.accessioned |
2021-07-23T05:22:03Z |
|
dc.date.available |
2021-07-23T05:22:03Z |
|
dc.date.issued |
2021-05 |
|
dc.identifier.citation |
Monthly Notices of the Royal Astronomical Society, Vol. 503, No. 1, pp. 446–457 |
en_US |
dc.identifier.issn |
1365-2966 |
|
dc.identifier.uri |
http://hdl.handle.net/2248/7807 |
|
dc.description |
Restricted Access |
en_US |
dc.description.abstract |
We carried out a detailed study of the temporal and broad-band spectral behaviour of one of the brightest misaligned active galaxies in γ-rays, NGC 1275, utilizing 11 years of Fermi data and the available Swift and AstroSat observations. Based on the cumulative flux distribution of the γ-ray light curve, we identified four distinct activity states and noticed an increase in the baseline flux during the first three states. A similar nature of increase in the average flux was also noticed in the X-ray and UV bands. Strong flaring activity in γ-rays was noticed in the fourth state. The source was observed twice by AstroSat for shorter intervals (∼days) during longer observing (∼years) states 3 and 4. During the AstroSat observing periods, the source γ-ray flux was higher than the average flux observed during longer duration states. The increase in average baseline flux from state 1 to state 3 can be explained by considering a corresponding increase of jet particle normalization. The inverse Comptonization of synchrotron photons explained the average X-ray and γ-ray emission by jet electrons during the first three longer duration states. However, during the shorter duration AstroSat observing periods, a shift of synchrotron peak frequency was noticed, and the synchrotron emission of jet electrons explained the observed X-ray flux well. |
en_US |
dc.language.iso |
en |
en_US |
dc.publisher |
Oxford University Press on behalf of the Royal Astronomical Society |
en_US |
dc.relation.uri |
https://doi.org/10.1093/mnras/stab244 |
|
dc.rights |
© The Royal Astronomical Society |
|
dc.subject |
Galaxies: active |
en_US |
dc.subject |
Galaxies: jets |
en_US |
dc.subject |
Quasars: individual: NGC 1275 |
en_US |
dc.subject |
Gamma-rays: galaxies |
en_US |
dc.subject |
X-rays: galaxies |
en_US |
dc.title |
Multiwavelength monitoring of NGC 1275 over a decade: evidence of a shift in synchrotron peak frequency and long-term multiband flux increase |
en_US |
dc.type |
Article |
en_US |