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Related papers: On the multi-wavelength Emission from CTA 102

200 papers

In this work, we provide a detailed analysis of the broadband temporal and spectral properties of the blazar Ton\,599 by using the observations from \emph{Fermi}-LAT and \emph{Swift}-XRT/UVOT telescopes, during its brightest $\gamma$-ray…

High Energy Astrophysical Phenomena · Physics 2024-03-04 Aaqib Manzoor , Zahir Shah , Sunder Sahayanathan , Naseer Iqbal , Athar A. Dar

In October 2024, the object BL Lacertae experienced the brightest flaring event in gamma-ray ($>$100 MeV) with a historically bright $\gamma$-ray flux of $\sim$2.59 $\times 10^{-5}$ erg cm$^{-2}$ s$^{-1}$ with a detection of a 175.7 GeV…

High Energy Astrophysical Phenomena · Physics 2025-07-08 Joysankar Majumdar , Sakshi Maurya , Raj Prince

We present long-term multiwavelength observations of blazar CTA 102 ($z=1.037$). Detailed temporal and spectral analyses of $\gamma$-ray, X-ray and UV/optical data observed by {\it Fermi}-LAT, Swift XRT, NuSTAR and Swift-UVOT over a period…

High Energy Astrophysical Phenomena · Physics 2022-10-26 N. Sahakyan , D. Israyelyan , G. Harutyunyan , S. Gasparyan , V. Vardanyan , M. Khachatryan

This paper presents the gamma-ray spectral and timing results from the long-term regular observations of Mrk 421 with the Large Area Telescope (LAT) onboard Fermi during 2008 August - 2023 August. We discerned six periods the relatively…

High Energy Astrophysical Phenomena · Physics 2025-03-05 B. Kapanadze , A. Gurchumelia , M. Aller

The blazar 4C 31.03 recently underwent a major gamma-ray outburst at the beginning of 2023 after a prolonged quiescent phase. Fermi-LAT reported a daily average flux of 5x10^-6 phs cm^-2 s^-1, which is about 60 times its average value. We…

High Energy Astrophysical Phenomena · Physics 2024-04-16 Aminabi Thekkoth , Baheeja C , S Sahayanathan , C D Ravikumar

We report results of a multiband monitoring campaign of the flat spectrum radio quasar TXS 0536+145 at redshift 2.69. This source was detected during a very high gamma-ray activity state in 2012 March by the Large Area Telescope on board…

High Energy Astrophysical Phenomena · Physics 2015-06-22 M. Orienti , F. D'Ammando , M. Giroletti , J. Finke , M. Ajello , D. Dallacasa , T. Venturi

We present results of spectrometric studies based on the observations of very strong 3C 279 flares in high and very-high-energy bands and discuss their implications regarding the origin of radiation mechanisms. The FSRQ 3C 279 (z=0.536) is…

High Energy Astrophysical Phenomena · Physics 2020-01-27 Davit Zargaryan , Carlo Romoli , Felix Aharonian

This is the first report of Fermi Gamma-ray Space Telescope observations of the quasar 3C 454.3, which has been undergoing pronounced long-term outbursts since 2000. The data from the Large Area Telescope (LAT), covering 2008 July 7 -…

High Energy Astrophysical Phenomena · Physics 2012-08-27 LAT Collaboration , A. A. Abdo

High redshift blazars are among the most powerful non-explosive sources in the Universe and play a crucial role in understanding the evolution of relativistic jets. To understand these bright objects, we performed a detailed investigation…

High Energy Astrophysical Phenomena · Physics 2024-01-29 N. Sahakyan , G. Harutyunyan , S. Gasparyan , D. Israyelyan

We report on multiwavelength observations of the blazar PKS 0537-441 (z = 0.896) obtained from microwaves through gamma rays by SMA, REM, ATOM, Swift and Fermi during 2008 August-2010 April. Strong variability has been observed in gamma…

The blazar AO 0235+164 (z = 0.94) has been one of the most active objects observed by Fermi Large Area Telescope (LAT) since its launch in Summer 2008. In addition to the continuous coverage by Fermi, contemporaneous observations were…

High Energy Astrophysical Phenomena · Physics 2012-07-13 M. Ackermann , M. Ajello , J. Ballet , G. Barbiellini , D. Bastieri , R. Bellazzini , R. D. Blandford , E. D. Bloom , E. Bonamente , A. W. Borgland , E. Bottacini , J. Bregeon , M. Brigida , P. Bruel , R. Buehler , S. Buson , G. A. Caliandro , R. A. Cameron , P. A. Caraveo , J. M. Casandjian , E. Cavazzuti , C. Cecchi , E. Charles , A. Chekhtman , J. Chiang , S. Ciprini , R. Claus , J. Cohen-Tanugi , S. Cutini , F. D'Ammando , F. de Palma , C. D. Dermer , E. do Couto e Silva , P. S. Drell , A. Drlica-Wagner , R. Dubois , C. Favuzzi , S. J. Fegan , E. C. Ferrara , W. B. Focke , P. Fortin , L. Fuhrmann , Y. Fukazawa , P. Fusco , F. Gargano , D. Gasparrini , N. Gehrels , S. Germani , N. Giglietto , P. Giommi , F. Giordano , M. Giroletti , T. Glanzman , G. Godfrey , I. A. Grenier , S. Guiriec , D. Hadasch , M. Hayashida , R. E. Hughes , R. Itoh , G. Johannesson , A. S. Johnson , H. Katagiri , J. Kataoka , J. Knodlseder , M. Kuss , J. Lande , S. Larsson , S. -H. Lee , F. Longo , F. Loparco , B. Lott , M. N. Lovellette , P. Lubrano , G. M. Madejski , M. N. Mazziotta , J. E. McEnery , J. Mehault , P. F. Michelson , W. Mitthumsiri , T. Mizuno , C. Monte , M. E. Monzani , A. Morselli , I. V. Moskalenko , S. Murgia , M. Naumann-Godo , S. Nishino , J. P. Norris , E. Nuss , T. Ohsugi , A. Okumura , N. Omodei , E. Orlando , M. Ozaki , D. Paneque , J. H. Panetta , V. Pelassa , M. Pesce-Rollins , M. Pierbattista , F. Piron , G. Pivato , T. A. Porter , S. Raino , R. Rando , D. Rastawicki , M. Razzano , A. Readhead , A. Reimer , O. Reimer , L. C. Reyes , J. L. Richards , C. Sbarra , C. Sgro , E. J. Siskind , G. Spandre , P. Spinelli , A. Szostek , H. Takahashi , T. Tanaka , J. G. Thayer , J. B. Thayer , D. J. Thompson , M. Tinivella , D. F. Torres , G. Tosti , E. Troja , T. L. Usher , J. Vandenbroucke , V. Vasileiou , G. Vianello , V. Vitale , A. P. Waite , B. L. Winer , K. S. Wood , Z. Yang , S. Zimmer , R. Moderski , K. Nalewajko , M. Sikora , M. Villata , C. M. Raiteri , H. D. Aller , M. F. Aller , A. A. Arkharov , E. Benitez , A. Berdyugin , D. A. Blinov , M. Boettcher , O. J. A. Bravo Calle , C. S. Buemi , D. Carosati , W. P. Chen , C. Diltz , A. Di Paola , M. Dolci , N. V. Efimova , E. Forn\' , M. A. Gurwell , J. Heidt , D. Hiriart , B. Jordan , G. Kimeridze , T. S. Konstantinova , E. N. Kopatskaya , E. Koptelova , O. M. Kurtanidze , A. Lahteenmaki , E. G. Larionova , L. V. Larionova , V. M. Larionov , P. Leto , E. Lindfors , H. C. Lin , D. A. Morozova , M. G. Nikolashvili , K. Nilsson , M. Oksman , P. Roustazadeh , A. Sievers , L. A. Sigua , A. Sillanpaa , T. Takahashi , L. O. Takalo , M. Tornikoski , C. Trigilio , I. S. Troitsky , G. Umana , E. Angelakis , T. P. Krichbaum , I. Nestoras , D. Riquelme , M. Krips , S. Trippe , A. Arai , K. S. Kawabata , K. Sakimoto , M. Sasada , S. Sato , M. Uemura , M. Yamanaka , M. Yoshida , T. Belloni , G. Tagliaferri , E. W. Bonning , J. Isler , C. M. Urry , E. Hoversten , A. Falcone , C. Pagani , M. Stroh

Almost 10 yr of $\gamma$-ray observations with the Fermi Large Area Telescope (LAT) have revealed extreme $\gamma$-ray outbursts from flat spectrum radio quasars (FSRQs), temporarily making these objects the brightest $\gamma$-ray emitters…

High Energy Astrophysical Phenomena · Physics 2020-01-31 Manuel Meyer , Jeffrey D. Scargle , Roger D. Blandford

Blazars are known to emit exceptionally variable non-thermal emission over the wide range (from radio to $\gamma$-rays) of electromagnetic spectrum. We present here the results of our $\gamma$-ray flux and spectral variability study of the…

High Energy Astrophysical Phenomena · Physics 2021-12-14 Bhoomika Rajput , Ashwani Pandey

The Fermi-LAT has observed new gamma-ray flares from the blazar B0218+357 during July 2014. While no significant change in the gamma-ray spectrum has been previously observed through the flaring phase in late-2012, during this recent high…

High Energy Astrophysical Phenomena · Physics 2015-02-12 S. Buson , C. C. Cheung , S. Larsson , J. D. Scargle

We report the detection of a new gamma-ray source in the Fermi-LAT sky using a source detection tool based on the Minimal Spanning Tree algorithm. The source, not reported in previous LAT catalogues but very recently observed in the X-rays…

High Energy Astrophysical Phenomena · Physics 2015-06-12 E. Bernieri , R. Campana , E. Massaro , A. Paggi , A. Tramacere

We investigate the $\gamma$-ray and X-ray properties of the flat spectrum radio quasar (FSRQ) \4c50 at redshift $z= 1.517$. The {\it Fermi} Large Area Telescope (LAT) data indicate that this source was in an active state since 2013 July.…

High Energy Astrophysical Phenomena · Physics 2021-06-03 Jianeng Zhou , V. Jithesh , Chen Liang , Zhongxiang Wang

An exceptional $\gamma$-ray outburst from 3C 279 is detected by {\it Fermi}-Large Area Telescope (LAT) in 2015 June. In the energy range of 0.1$-$300 GeV, the highest flux measured is (39.1$\pm$2.5) $\times$ 10$^{-6}$ \phflux, which is the…

High Energy Astrophysical Phenomena · Physics 2015-08-06 Vaidehi S. Paliya

In the first 3.5 years of operations the Fermi LAT detected several sources with daily fluxes brighter than F(E>100MeV) > 10^{-6} ph/cm^2/s, the threshold set by the Fermi Collaboration for issuing an Astronomer Telegram. We focus the…

High Energy Astrophysical Phenomena · Physics 2013-03-13 S. Buson , D. Bastieri , F. D'Ammando , G. Tosti