Imaging and photometric studies of NGC 1316 (Fornax A) using Astrosat/UVIT

• Published in: Journal of astrophysics and astronomy 2021-10, Vol.42 (2), Article 34
• Main Authors: Vagshette, Nilkanth D., Naik, Sachindra, Kumari, Neeraj, Patil, Madhav K.
• Format: Article
• Language: English
• Subjects: Active galactic nuclei; Astronomy; Astrophysics and Astroparticles; AstroSat: Five Years in Orbit; Emission analysis; Emissions; Galaxies; Imaging; Observations and Techniques; Photometry; Physics; Physics and Astronomy; Radio emission; Radio galaxies; Radio jets (astronomy); Science Results; Screen effect; Spatial resolution; Star & galaxy formation; Star formation; Subtraction; Telescopes; Ultraviolet telescopes
• ISSN: 0250-6335; 0973-7758
• DOI: 10.1007/s12036-021-09708-4

We present imaging and photometric studies of the radio galaxy NGC 1316 (Fornax A) using high spatial resolution near-ultraviolet (NUV) and far-ultraviolet (FUV) imaging telescopes of the first Indian multi-wavelength space observatory AstroSat. The residual maps of UV emission obtained from the subtraction of smooth models witness peculiar features within the central few kpc (1–2 kpc) region. The spatial correspondence between the radio emission maps and FUV imaging study reveal that the UV emitting sources are displaced away from the centre by the AGN outburst (radio jet). The presence of rims and clumpy structures in the outskirt of this galaxy delineate that the galaxy has acquired a large fraction of gas through merger-like events and is still in the process of settling. The estimates of the star formation rates (SFR) using FUV and NUV luminosities are found to be 0.15 M ⊙ yr - 1 and 0.36 M ⊙ yr - 1 , respectively, and provide the lower limit due to the screen effect. The estimated lower rates of SFR in this galaxy probably represent its quenching due to the AGN driven outflows emanating from the central engine of NGC 1316.