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Related papers: Gamma-loud quasars: a view with BeppoSAX

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We present the results from the Suzaku X-ray observations of five flat-spectrum radio quasars (FSRQs), namely PKS0208-512, Q0827+243, PKS1127-145, PKS1510-089 and 3C 454.3. All these sources were additionally monitored simultaneously or…

High Energy Astrophysical Phenomena · Physics 2015-05-18 LAT Collaboration , A. A. Abdo , F. Tavecchio , M. Sikora , P. Schady , P. Roming , M. M. Chester , L. Maraschi

We present the results of a systematic analysis of the XMM-Newton spectra of nearby optically bright QSOs. The objects have been selected from X-ray Galaxy Catalog Xgal20. It is a catalog of 1172 manually identified and classified galaxies,…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-15 Lidiia Zadorozhna , Anatolii Tugay , Nadiia Pulatova , Oleh Maluy

We present near-infrared spectroscopy of ten weak emission-line quasars (WLQs) at redshifts of $z\sim2$, obtained with the Palomar 200-inch Hale Telescope. WLQs are an exceptional population of type 1 quasars that exhibit weak or no broad…

We report the detection of the 6.4 keV Iron K{\alpha} emission line in two infrared-luminous, massive, star-forming BzK galaxies at z = 2.578 and z = 2.90 in the CDF-S. The Chandra 4 Ms spectra of BzK4892 and BzK8608 show a reflection…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 C. Feruglio , E. Daddi , F. Fiore , D. M. Alexander , E. Piconcelli , C. Malacaria

We report the discovery by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope of high-energy gamma-ray emission from the peculiar quasar PMN J0948+0022 (z=0.5846). The optical spectrum of this object exhibits rather…

High Energy Astrophysical Phenomena · Physics 2012-08-27 LAT Collaboration , A. A. Abdo , G. Ghisellini , L. Maraschi , F. Tavecchio , E. Angelakis

ASCA's long look at the 288 millisecond radio pulsar, PSR J0631+1036, reveals coherent X-ray pulsation from this source for the first time. The source was first detected in the serendipitous Einstein observation and later identified as a…

We report on soft X-ray observations of the Seyfert 1 galaxy MCG-6-30-15 with the Low and Medium Energy Concentrator Spectrometers on board BeppoSAX. The time averaged 0.1-4 keV spectrum shows evidence for a complex warm absorber. K-edges…

Astrophysics · Physics 2008-02-03 Astrid Orr , S. Molendi , F. Fiore , P. Grandi , A. N. Parmar , Alan Owens

We present broad-band (0.1--90keV) spectral and temporal properties of the three Intermediate Polars, RE0751+144 (PQ Gem), RXJ0558.0+5353 (V405Aur) and RXJ1712.6-2414 (V2400 Oph) based on simultaneous soft and hard X-ray observations with…

Astrophysics · Physics 2009-11-10 D. de Martino , G. Matt , T. Belloni , F. Haberl , K. Mukai

We report multi-wavelength (IR-O, UV, X-ray, gamma-ray) data of the flat spectrum radio quasar (FSRQ) PKS B1424-418 (z=1.52) gathered during an active phase in 2013 April . As for a few other cases of FSRQs reported in literature, the…

High Energy Astrophysical Phenomena · Physics 2015-06-16 F. Tavecchio , L. Pacciani , I. Donnarumma , A. Stamerra , J. Isler , E. MacPherson , C. M. Urry

We report the hard X-ray spectrum of the Coma cluster obtained using the PDS data of two independent BeppoSAX observations performed with a time interval of about three years. In both the spectra a non thermal excess with respect to the…

We report on highlight results on celestial sources observed in the high energy band (>20 keV) with BeppoSAX. In particular we review the spectral properties of sources that belong to different classes of objects, i.e. stellar coronae…

We report the COMPTEL detection of pulsed $\gamma$-emission from PSR B1509-58 up to at least 10 MeV using data collected over more than 6 years. The 0.75-10 MeV lightcurve is broad and reaches its maximum near radio-phase 0.38, slightly…

We study the quasi-simultaneous near-IR, optical, UV, and X-ray photometry of eleven gamma-ray selected blazars for which redshift estimates larger than 1.2 have been recently provided. Four of these objects turn out to be high-power…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 P. Padovani , P. Giommi , A. Rau

We report the discovery of a radio loud quasar with a redshift of 4.30. This object, which is the first radio selected quasar with a redshift greater than four, was discovered during an observational investigation into the evolution of the…

Mkn 841 has been observed simultaneously by XMM and BeppoSAX in January 2001. Due to operational contingency, the 30ks XMM observation was split into two parts, separated by about 15 hours. We first report the presence of a narrow iron line…

The X-ray telescopes on board BeppoSAX are an optimal set of instruments to observe bright galactic binary pulsars. These sources emit very hard and quite complex X-ray spectra that can be accurately measured with BeppoSAX between 0.1 and…

We report on an observation of the low-mass X-ray binary 4U1626-67 performed during the BeppoSAX Science Verification Phase. An absorption feature at ~37 keV, attributable to electron cyclotron resonance, has been discovered in its pulse…

New class of low- ionization BAL quasars (Becker et al. 1997), represented by QSO 1556+3517, 0840+3633 and 0059-2735, is considered. Their optical spectra are completely dominated by absorption features, whereas emission lines are weak or…

Astrophysics · Physics 2007-05-23 V. K. Dubrovich , A. A. Lipovka

Flat spectrum radio quasars (FSRQs) can suffer strong absorption above E = 25/(1+z) GeV, due to gamma-gamma interaction if the emitting region is at sub-parsec scale from the super-massive black hole (SMBH). Gamma-ray flares from these…

High Energy Astrophysical Phenomena · Physics 2018-08-22 G. Piano , P. Munar-Adrover , L. Pacciani , P. Romano , S. Vercellone , I. Donnarumma , F. Verrecchia , L. Carrasco , A. Porras , E. Recillas , M. Tavani

We report a Chandra high-energy grating detection of a narrow, redshifted absorption line superimposed on the red wing of a broad Fe K line in the $z=0.297$ quasar E1821+643. The absorption line is detected at a confidence level, estimated…

Astrophysics · Physics 2009-11-10 T. Yaqoob , P. J. Serlemitsos
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