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We investigate the cyclotron resonant scattering features (CRSFs) of the accreting X-ray pulsar Cen X-3 and significantly detect the 29 keV cyclotron line features in the hard X-ray averaged spectroscopy studies based on the recent…

High Energy Astrophysical Phenomena · Physics 2024-10-29 Qi Liu , Wei Wang , Wen Yang , Xiao Chen , Hanji Wu

We present ~400ks NuSTAR observations of the northeast (NE) and southwest (SW) non-thermal limbs of the Galactic SNR SN1006. We discovered three sources with X-ray emission detected at >50keV. Two of them are identified as background AGN.…

High Energy Astrophysical Phenomena · Physics 2018-09-19 Jiang-Tao Li , Jean Ballet , Marco Miceli , Ping Zhou , Jacco Vink , Yang Chen , Fabio Acero , Anne Decourchelle , Joel N. Bregman

We present the analysis of five joint XMM-Newton/NuSTAR observations, 20 ks each and separated by 12 days, of the broad-line radio galaxy 3C 382. The data were obtained as part of a campaign performed in September-October 2016…

We present light curves and flares from a seven day, multi-wavelength observational campaign of AU Mic, a young and active dM1e star with exoplanets and a debris disk. We report on 73 unique flares between the X-ray to optical data. We use…

An X1.6 flare occurred in AR 12192 on 2014 October 22 at 14:02 UT and was observed by Hinode, IRIS, SDO, and RHESSI. We analyze a bright kernel which produces a white light (WL) flare with continuum enhancement and a hard X-ray (HXR) peak.…

Solar and Stellar Astrophysics · Physics 2017-02-22 Kyoung-Sun Lee , Shinsuke Imada , Kyoko Watanabe , Yumi Bamba , David H. Brooks

We report the detection of emission from a non-thermal electron distribution in a small solar microflare (GOES class A5.7) observed by the Nuclear Spectroscopic Telescope Array (NuSTAR), with supporting observation by the Reuven Ramaty High…

We use archival data of NASA's Chandra X-ray telescope to compile an X-ray light curve of all four images of the quadruply lensed quasar Q2237+0305 (z=1.695) from January 2006 to January 2007. We fit simulated point spread functions to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 F. Zimmer , R. W. Schmidt , J. Wambsganss

We present the results of the blazar 3C 345 monitoring in Johnson-Cousins BVRI bands for the period 1996 - 2006. We have collected 29 V and 43 R data points for this period; the BI light curves contain a few measurements only. The accuracy…

Astrophysics · Physics 2009-11-13 B. Mihov , R. Bachev , L. Slavcheva-Mihova , A. Strigachev , E. Semkov , G. Petrov

We present the results from a detailed analysis of the 2007 Swift monitoring campaign of the quasar PG1211+143. We constructed broad-band, optical/UV/X-ray spectral energy distributions over three X-ray flux intervals. We fitted them with a…

Astrophysics of Galaxies · Physics 2016-06-22 I. E. Papadakis , F. Nicastro , C. Panagiotou

We have discovered extended X-ray emission from the microquasar Cyg X-3 in archival Chandra X-ray Observatory observations. A 5" wide structure lies approximately 16" to the NE from the core point source and may be extended in that…

Astrophysics · Physics 2009-11-07 W. A. Heindl , J. A. Tomsick , R. Wijnands , D. M. Smith

The blazar 3C454.3 exhibited a strong flare seen in gamma-rays, X-rays, and optical/NIR bands during 3--12 December 2009. Emission in the V and J bands rose more gradually than did the gamma-rays and soft X-rays, though all peaked at nearly…

We followed-up the massive young stellar object (MYSO) S255-NIRS3 (=S255-IRS1b) during its recent accretion outburst event in the Ks band with Kanata/HONIR for four years after its burst and obtained a long-term light curve. This is the…

Microquasars have been expected to emit high energy gamma-rays due to their general similarities to the gamma-ray emitting blazars (evidences of relativistic jets, non-thermal radio to X-ray emission). In fact, the first source of this…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Julian Sitarek , Włodzimierz Bednarek

In 3C 273, ultraviolet flux and X-ray flux measured by BATSE are not well correlated, contrarily to predictions of several models, unless the X-ray flux lags the UV emission by 1.75 yr. The absence of observed correlation at small lag…

Astrophysics · Physics 2015-06-24 S. Paltani , T. J. -L. Courvoisier , M. Turler , R. Walter

The blazar 3C 279 exhibited twin $\gamma$-ray flares of similar intensity in 2013 December and 2014 April. In this work, we present a detailed multi-wavelength analysis of the 2013 December flaring event. Multi-frequency observations reveal…

High Energy Astrophysical Phenomena · Physics 2016-01-27 Vaidehi S. Paliya , Chris Diltz , Markus Bottcher , C. S. Stalin , David Buckley

We report the results of XMM-Newton and BeppoSAX observations of the radio and X-ray emitting star LS I +61 303, likely associated with the gamma-ray source 2CG 135+01 and recently detected also at TeV energies. The data include a long…

We perform a detailed spectral study of a recent flaring activity from the Flat Spectrum Radio Quasar (FSRQ), 3C\,454.3, observed simultaneously in optical, UV, X-ray and $\gamma$-ray energies during 16 to 28 August, 2015. The source…

High Energy Astrophysical Phenomena · Physics 2017-05-18 Zahir Shah , S. Sahayanathan , Nijil Mankuzhiyil , Pankaj Kushwaha , Ranjeev Misra , Naseer Iqbal

The emission mechanisms of the blazar 3C 279 are studied by solving the kinetic equations of electrons and photons in a relativistically moving blob. The gamma-ray spectral energy distribution (SED) is fitted by inverse Compton scattering…

Astrophysics · Physics 2009-11-10 Masaaki Kusunose , Fumio Takahara , Tomohiro Kato

Using an unprecedented cadence of 30 minutes provided by the Transiting Exoplanet Survey Satellite (TESS), we have examined the optical light curves (LCs) of the blazar S5 0716+714 obtained from its Sectors 40, 47, and 53 over a period of…

High Energy Astrophysical Phenomena · Physics 2026-03-09 Shubham Kishore , Alok C. Gupta , Paul J. Wiita

LSI +61 303 is an exotic binary system consisting of a ~10 Msun B star and a compact object which is probably a neutron star. The system is associated with the interesting radio source GT0236+610 that exhibits bright radio outbursts with a…

Astrophysics · Physics 2009-10-30 P. S. Ray , R. S. Foster , E. B. Waltman , M. Tavani , F. D. Ghigo
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