Zobrazeno 1 - 10
of 22
pro vyhledávání: '"G C Dewangan"'
Autor:
Pragati Sahu, Swadesh Chand, Parijat Thakur, G. C. Dewangan, V. K. Agrawal, Prakash Tripathi, Subhashish Das
Publikováno v:
The Astrophysical Journal, Vol 975, Iss 2, p 165 (2024)
We perform a comprehensive timing and broadband spectral analysis using an AstroSat observation of the low-mass black hole X-ray binary H 1743–322 during its 2017 outburst. Additionally, we use two Swift/XRT observations, one of which is simultaneo
Externí odkaz:
https://doaj.org/article/bf4022537c76432dada6159b587dcfd8
Autor:
Shrabani Kumar, G. C. Dewangan, P. Gandhi, I. E. Papadakis, N. P. S. Mithun, K. P. Singh, D. Bhattacharya, A. A. Zdziarski, G. C. Stewart, S. Bhattacharyya, S. Chandra
Publikováno v:
The Astrophysical Journal, Vol 975, Iss 1, p 73 (2024)
We present a multiwavelength spectral study of NGC 4151 based on five epochs of simultaneous AstroSat observations in the near-ultraviolet (NUV) to hard X-ray band (∼0.005–80 keV) during 2017–2018. We derived the intrinsic accretion disk contin
Externí odkaz:
https://doaj.org/article/0cdd62f880f54f6881e46bb8f2b6885b
Autor:
Shrabani Kumar, G. C. Dewangan, K. P. Singh, P. Gandhi, I. E. Papadakis, P. Tripathi, L. Mallick
Publikováno v:
The Astrophysical Journal, Vol 950, Iss 2, p 90 (2023)
We study accretion disk emission from eight Seyfert 1–1.5 active galactic nuclei (AGN) using far-ultraviolet (FUV) (1300–1800 Å) slitless grating spectra acquired with AstroSat/UVIT. We correct for the Galactic and intrinsic extinction, contamin
Externí odkaz:
https://doaj.org/article/21c36cc626b04a6bb6cc30234b01c5a1
Autor:
Kavita Kumari, G C Dewangan, I E Papadakis, Max W J Beard, I M McHardy, K P Singh, D Bhattacharya, S Bhattacharyya, S Chandra
We study accretion disk-corona connection in Seyfert 1 galaxies using simultaneous UV/X-ray observations of NGC 4593 (July 14-18, 2016) and NGC 7469 (October 15-19, 2017) performed with AstroSat. We use the X-ray (0.5-7.0 keV) data acquired with the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3d386a8d171960e2bc3db3a9956e4724
http://arxiv.org/abs/2303.01556
http://arxiv.org/abs/2303.01556
AstroSat view of the newly discovered X-ray transient MAXI~J1803--298 in the Hard-intermediate state
We perform comprehensive temporal and spectral analysis of the newly discovered X-ray transient MAXI~J1803--298 using an AstroSat target of opportunity observation on May 11, 2021 during its outburst. The source was found to be in the hard intermedia
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::eda4c57c2a7061c3afadc32b610e1f53
http://arxiv.org/abs/2112.03556
http://arxiv.org/abs/2112.03556
Publikováno v:
Astronomy & Astrophysics. 390:65-80
(Abridged) We present an analysis of a 10-day continuous ASCA observation of the narrow-line Seyfert 1 galaxy IRAS 13224-3809. The soft (0.7-1.3 keV) and hard (1.3-10 keV) X-ray band light curves binned to 5000s reveal trough-to-peak variations by a
Autor:
Kulinder Pal Singh, S. N. Tandon, P. C. Agrawal, H. M. Antia, R. K. Manchanda, J. S. Yadav, S. Seetha, M. C. Ramadevi, A. R. Rao, D. Bhattacharya, B. Paul, P. Sreekumar, S. Bhattacharyya, G. C. Stewart, J. Hutchings, S. A Annapurni, S. K. Ghosh, J. Murthy, A. Pati, N. K. Rao, C .S. Stalin, V. Girish, K. Sankarasubramanian, S. Vadawale, V. B. Bhalerao, G. C. Dewangan, D. K. Dedhia, M. K. Hingar, T. B. Katoch, A. T. Kothare, I. Mirza, K. Mukerjee, H. Shah, P. Shah, R. Mohan, A. K. Sangal, S. Nagabhusana, S. Sriram, J. P. Malkar, S. Sreekumar, A. F. Abbey, G. M. Hansford, A. P. Beardmore, M. R. Sharma, S. Murthy, R. Kulkarni, G. Meena, V. C. Babu, J. Postma
Is India'€™s first astronomy satellite that will carry an array of instruments capable of simultaneous observations in a broad range of wavelengths: from the visible, near ultraviolet (NUV), far-UV (FUV), soft X-rays to hard X-rays. There will be
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9ee3c02166d2ca2578c24ac80871bc0d
https://nrc-publications.canada.ca/eng/view/object/?id=27ca9ba3-dbf6-476c-96eb-94d1933a45ff
https://nrc-publications.canada.ca/eng/view/object/?id=27ca9ba3-dbf6-476c-96eb-94d1933a45ff
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 325:1616-1624
We report the discovery of a narrow-line QSO (NLQSO) RX J1334.2+3759 with a steep soft X-ray spectrum. Soft X-ray emission from the NLQSO is highly variable. Changes in the intensity by a factor of about 2 have been detected in the ROSAT PSPC observa
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 318:309-320
We report the discovery of an active nucleus in a poststarburst galaxy, KUG1259+280. High resolution X-ray imaging observations with ROSAT HRI show that X-ray emission from KUG1259+280 is unresolved. X-ray emission from KUG1259+280 is highly variable