Zobrazeno 1 - 10
of 83
pro vyhledávání: '"Nayantara Gupta"'
Autor:
Samik Dutta, Nayantara Gupta
Publikováno v:
The Astrophysical Journal, Vol 974, Iss 1, p 56 (2024)
The Large High Altitude Air Shower Observatory (LHAASO) has detected very-high-energy gamma rays from the low-ionization nuclear emission-line region galaxy NGC 4278, which has a low-luminosity active galactic nucleus (LLAGN) and symmetric, mildly re
Externí odkaz:
https://doaj.org/article/20ddc2c67f014b8b84249fffede79d04
Autor:
Sovan Boxi, Nayantara Gupta
Publikováno v:
The Astrophysical Journal, Vol 961, Iss 1, p 61 (2024)
The very-high-energy γ -ray source HESS J1809-193 has been detected by the LHAASO and HAWC observatory beyond 100 TeV energy. It is an interesting candidate for exploring the underlying mechanisms of γ -ray production due to the presence of superno
Externí odkaz:
https://doaj.org/article/ab10ed0093ce4996ade121a461b0466f
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 1, Pp 1-15 (2021)
Abstract We fit the ultrahigh-energy cosmic-ray (UHECR, $$E\gtrsim 0.1$$ E ≳ 0.1 EeV) spectrum and composition data from the Pierre Auger Observatory at energies $$E\gtrsim 5\cdot 10^{18}$$ E ≳ 5 · 10 18 eV, i.e., beyond the ankle using two popu
Externí odkaz:
https://doaj.org/article/dc2eeca0130049cf85f6f5cf11905ad3
Publikováno v:
The Astrophysical Journal, Vol 948, Iss 2, p 75 (2023)
Markarian (Mrk) 180 is a BL Lacertae object located at a redshift of 0.045 and is a potential candidate for high-energy cosmic-ray acceleration. We have analyzed the Fermi Large Area Telescope (Fermi-LAT) γ -ray data of Mrk 180 collected over a peri
Externí odkaz:
https://doaj.org/article/765589e6826b4ee1b37e77da5a8f710b
Autor:
Gunjan Tomar, Nayantara Gupta
Publikováno v:
The Astrophysical Journal, Vol 950, Iss 2, p 113 (2023)
Most active galactic nuclei at the center of the nearby galaxies have supermassive black holes accreting at sub-Eddington rates through hot accretion flows or radiatively inefficient accretion flows, which efficiently produce jets. The association of
Externí odkaz:
https://doaj.org/article/8e7e94636dc6426d81932189cd79e937
Publikováno v:
INSPIRE-HEP
Markarian (Mrk) 180 is a BL Lacertae (BL Lac) object located at a redshift of 0.045 and a potential candidate for high-energy cosmic ray acceleration. We have analyzed the Fermi Large Area Telescope (\textit{Fermi}-LAT) $\gamma$-ray data of Mrk 180 c
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::26b67752aa167b5359a1cd01eceab502
http://arxiv.org/abs/2212.07331
http://arxiv.org/abs/2212.07331
MAGIC collaboration has recently analyzed data from a long-term multiwavelength campaign of the $\gamma$-ray blazar TXS 0506+056. In December 2018, it was flaring in the very-high-energy (VHE; $E>100$ GeV) $\gamma$-ray band, but no simultaneous neutr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::125e2d69ff65b2dd6fc460740c1d9846
http://arxiv.org/abs/2208.00838
http://arxiv.org/abs/2208.00838
Secondary positrons produced inside Galactic Molecular Clouds (GMCs) can significantly contribute to the observed positron spectrum on Earth. Multi-wavelength data of GMCs are particularly useful in building this model. A very recent survey implement
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8e6679c00a6ad1a373104961fc6fcbcf
http://arxiv.org/abs/2202.13333
http://arxiv.org/abs/2202.13333
One of the most important questions in blazar physics is the origin of broadband emission and fast-flux variation. In this work, we studied the broadband temporal and spectral properties of a TeV blazar 1ES 1727+502 and explore the one-zone synchrotr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::1e7320820e6f7aeda846b3619c464188
Autor:
Agnibha De Sarkar, Nayantara Gupta
Recent observations by the Large High Altitude Air Shower Observatory (LHAASO) have paved the way for the observational detection of PeVatrons in the Milky Way Galaxy, thus revolutionizing the field of $\gamma$-ray astrophysics. In this paper, we stu
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4fea0284a60d0e7962a89f2d25830d95