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Related papers: X-ray observations during a Her X-1 anomalous low-…

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BeppoSAX observed the z=3.27 quasar PKS2126-158 on 1999 May 24-28 when its 2-10keV and 0.1-2.5keV fluxes were 1.1E-11 and 4.4E-12 cgs respectively, a factor of 2 higher than in all previous ROSAT and ASCA observations and 40% higher than in…

We report results from analysis of the observations of the dipping low mass X-ray binary XB 1323-619 made with BeppoSAX} and Rossi-XTE. The dust-scattered halo contributes significantly in this source, and the observation made with BeppoSAX…

Astrophysics · Physics 2009-11-07 R. Barnard , M. Balucinska-Church , A. P. Smale , M. J. Church

The X-ray pulsar SAX J0635+0533 was repeatedly observed with the XMM-Newton satellite in 2003-2004. The precise localization provided by these observations confirms the association of SAX J0635+0533 with a Be star. The source was found, for…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Sandro Mereghetti , Nicola La Palombara

Observations of Hercules X-1 by the Extreme Ultraviolet Explorer (EUVE) covering low state and the early part of the Short High state are reported here. This is the first EUV observation of this part of the 35-day cycle of Her X-1. The low…

Astrophysics · Physics 2009-10-31 D. A. Leahy , H. Marshall , D. Scott

We present the results from the RXTE observations of Cygnus X-1 in its high state. In the energy range of 2-200 keV, the observed X-ray spectrum can be described by a model consisting of a soft blackbody component and a broken power-law…

Astrophysics · Physics 2015-06-24 W. Cui , W. A. Heindl , R. E. Rothschild , S. N. Zhang , K. Jahoda , W. Focke

We have obtained a far-ultraviolet spectrum of the X-ray binary Hercules X-1/HZ Herculis using the Hopkins Ultraviolet Telescope aboard the Astro-1 space shuttle mission in 1990 December. This is the first spectrum of Her X-1 that extends…

Astrophysics · Physics 2009-10-30 B. Boroson , W. P. Blair , A. F. Davidsen , S. D. Vrtilek , J. Raymond , K. S. Long , R. McCray

We report results of analysis of the ASCA observation of the Low Mass X-ray Binary dipping source XB1916-053 made on 1993, May 2nd. We have shown that the spectra can be well fitted by the same two-component model previously used to give…

Astrophysics · Physics 2009-10-30 M. J. Church , T. Dotani , M. Balucinska-Church , K. Mitsuda , T. Takahashi , H. Inoue , K. Yoshida

We present the results of a series of XMM-Newton EPIC and OM observations of Her X-1, spread over a wide range of the 35 d precession period. We confirm that the spin modulation of the neutron star is weak or absent in the low state - in…

Astrophysics · Physics 2009-11-10 S. Zane , G. Ramsay , M. A. Jimenez-Garate , J. W. den Herder , M. Still , P. T. Boyd , C. J. Hailey

We report on the first XMM-Newton observation of the Anomalous X-ray Pulsar 1RXS J170849.0-400910. The source was observed in 2003 August and was found at a flux level a factor of about two lower than previous observations. Moreover, a…

Astrophysics · Physics 2009-11-11 N. Rea , T. Oosterbroek , S. Zane , R. Turolla , M. Mendez , G. L. Israel , L. Stella , F. Haberl

We present the hard X-ray (20-100 keV) observations of Cygnus X-1 obtained using a large area balloon-borne Xenon filled Multi-anode Proportional Counter (XMPC) telescope. The observations were carried out during the gamma_2 state of the…

Astrophysics · Physics 2007-05-23 V. R. Chitnis , A. R. Rao , P. C. Agrawal

We report the results of Chandra and XMM-Newton observations of an ultra-luminous supersoft X-ray source in M101. M101 ULX-1 underwent 2 outbursts in 2004 during which the peak bolometric luminosities reached 1e41 erg/s. The outburst…

Astrophysics · Physics 2007-05-23 A. K. H. Kong , M. P. Rupen , L. O. Sjouwerman , R. Di Stefano

We present XMM-Newton and Chandra observations of 1E1048.1-5937, being the first to show evidence for a significant variation in the X-ray luminosity of this Anomalous X-ray Pulsar (AXP). While during the first XMM-Newton (2000 December)…

Astrophysics · Physics 2009-11-10 S. Mereghetti , A. Tiengo , L. Stella , G. L. Israel , N. Rea , S. Zane , T. Oosterbroek

(abridged) We analyzed the archived XMM-Newton observation of the poorly studied low-mass X-ray binary XTE J1710-281 performed in 2004 that covered one orbital period of the system (3.8 hr). The source shows dips as well as eclipses, hence…

High Energy Astrophysical Phenomena · Physics 2015-05-13 G. Younes , L. Boirin , B. Sabra

We report results of five pointed BeppoSAX observations of the black hole candidate 4U 1630-47 during part of its 1998 outburst when the 2-10 keV source luminosity decreased from 2.1x10^38 erg/s (for an assumed distance of 10 kpc) by a…

We present the results of a series of XMM-Newton EPIC and OM observations of Her X-1, spread over a wide range of the 35 day precession period. We confirm that the spin modulation of the neutron star is weak or absent in the low state - in…

Suzaku TOO observation of the anomalous X-ray pulsar CXOU J164710.2-455216 was performed on 2006 September 23--24 for a net exposure of 38.8 ks. During the observation, the XIS was operated in 1/8 window option to achieve a time resolution…

We report on the results of the longest uninterrupted observation of the Anomalous X-ray Pulsar 1RXS J1708-4009 obtained with the BeppoSAX satellite in August 2001. In the phase-resolved spectrum, corresponding to the rising part of the…

Astrophysics · Physics 2009-11-10 Nanda Rea , Gian Luca Israel , Luigi Stella

We present two new XMM-Newton observations of an unprecedented low flux state in the Seyfert 1 Mrk 1048 (NGC 985), taken in 2013. The X-ray flux below 1 keV drops by a factor of 4-5, whereas the spectrum above 5 keV is essentially…

High Energy Astrophysical Phenomena · Physics 2015-06-22 M. L. Parker , N. Schartel , S. Komossa , D. Grupe , M. Santos-Lleó A. C. Fabian , S. Mathur

We report the discovery of type-I X-ray bursts from the low-mass X-ray binary 4U 1708-40 during the 100 ks observation performed by BeppoSAX on 1999 August 15-16. Six X-ray bursts have been observed. The unabsorbed 2-10 keV fluxes of the…

We report on two new XMM-Newton observations of the Anomalous X-ray Pulsar (AXP) 4U 0142+614 performed in March and July 2004, collecting the most accurate spectrum for this source to date. Furthermore, we analyse two short archival…