TY - JOUR
T1 - Multiwavelength study of radio galaxy Pictor A
T2 - detection of western hotspot in far-UV and possible origin of high energy emissions
AU - Gulati, Sanna
AU - Bhattacharya, Debbijoy
AU - Ramadevi, M. C.
AU - Stalin, C. S.
AU - Sreekumar, P.
N1 - Funding Information:
We thank the anonymous referee for constructive comments that helped us to improve the manuscript considerably. We thank Rick Perley for providing radio images from Perley et al. (1997). The author(s) thank Swathi B for help regarding the astrometric corrections of UVIT images. The author(s) thank Dr Shalima P. for discussions on intrinsic dust corrections. The author(s) acknowledge the financial support of Indian Space Research Organisation (ISRO) under AstroSat archival Data utilization program. This publication uses the data from the AstroSat mission of the ISRO, archived at the Indian Space Science Data Centre (ISSDC). This work has been performed utilizing the calibration data bases and auxiliary analysis tools developed, maintained, and distributed by AstroSat-SXT team with members from various institutions in India and abroad. This work has made use of public Fermi-LAT data obtained from the Fermi Science Support Center (FSSC), provided by NASA Goddard Space Flight Center. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, and NEOWISE, which is a project of the Jet Propulsion Laboratory/California Institute of Technology. WISE and NEOWISE are funded by the National Aeronautics and Space Administration. Manipal Centre for Natural Sciences, Centre of Excellence, Manipal Academy of Higher Education (MAHE) is acknowledged for facilities and support.
Funding Information:
IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation
Funding Information:
We thank the anonymous referee for constructive comments that helped us to improve the manuscript considerably. We thank Rick Perley for providing radio images from Perley et al. (). The author(s) thank Swathi B for help regarding the astrometric corrections of UVIT images. The author(s) thank Dr Shalima P. for discussions on intrinsic dust corrections. The author(s) acknowledge the financial support of Indian Space Research Organisation (ISRO) under AstroSat archival Data utilization program. This publication uses the data from the AstroSat mission of the ISRO, archived at the Indian Space Science Data Centre (ISSDC). This work has been performed utilizing the calibration data bases and auxiliary analysis tools developed, maintained, and distributed by AstroSat-SXT team with members from various institutions in India and abroad. This work has made use of public Fermi-LAT data obtained from the Fermi Science Support Center (FSSC), provided by NASA Goddard Space Flight Center. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, and NEOWISE, which is a project of the Jet Propulsion Laboratory/California Institute of Technology. WISE and NEOWISE are funded by the National Aeronautics and Space Administration. Manipal Centre for Natural Sciences, Centre of Excellence, Manipal Academy of Higher Education (MAHE) is acknowledged for facilities and support.
Publisher Copyright:
© 2023 The Author(s).
PY - 2023/5/1
Y1 - 2023/5/1
N2 - A comprehensive study of the nucleus and western hotspot of Pictor A is carried out using AstroSat observations, 13 yr of Fermi, and archival Swift observations along with other published data. We report the first detection of the western hotspot of Pictor A in the far-UV band using observations from AstroSat-UVIT. The broad-band SED of the western hotspot is explained by a multizone emission scenario, where X-ray emission is caused by synchrotron emission process in the substructures embedded in the diffuse region, while the emission in radio to optical is caused by synchrotron emission process in the diffuse region. We do not notice any excess in the IR band and an additional zone (beyond 2-zone) is not required to account for the X-ray emission. Our broad-band spectro-temporal study and associated modelling of the core and hotspot of Pictor A suggests that (a) γ-rays originate in the nuclear jet and not from the hotspot (b) X-ray emission from the core of Pictor A has nuclear jet-origin instead of previously reported disc-origin.
AB - A comprehensive study of the nucleus and western hotspot of Pictor A is carried out using AstroSat observations, 13 yr of Fermi, and archival Swift observations along with other published data. We report the first detection of the western hotspot of Pictor A in the far-UV band using observations from AstroSat-UVIT. The broad-band SED of the western hotspot is explained by a multizone emission scenario, where X-ray emission is caused by synchrotron emission process in the substructures embedded in the diffuse region, while the emission in radio to optical is caused by synchrotron emission process in the diffuse region. We do not notice any excess in the IR band and an additional zone (beyond 2-zone) is not required to account for the X-ray emission. Our broad-band spectro-temporal study and associated modelling of the core and hotspot of Pictor A suggests that (a) γ-rays originate in the nuclear jet and not from the hotspot (b) X-ray emission from the core of Pictor A has nuclear jet-origin instead of previously reported disc-origin.
UR - https://www.scopus.com/pages/publications/85161648693
UR - https://www.scopus.com/inward/citedby.url?scp=85161648693&partnerID=8YFLogxK
U2 - 10.1093/mnras/stad716
DO - 10.1093/mnras/stad716
M3 - Article
AN - SCOPUS:85161648693
SN - 0035-8711
VL - 521
SP - 2704
EP - 2715
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 2
ER -