Science with the XEUS High Time Resolution Spectrometer (2008)
Barret, D., Belloni, T., Bhattacharyya, S., Cackett, E., Gilfanov, M., Gigus, E., ...
XEUS has been recently selected by ESA for an assessment study. XEUS is a large mission candidate for the Cosmic Vision program, aiming for a launch date as early as 2018. XEUS is a follow-on to...
Exploring a SNR/Molecular Cloud Association Within HESS J1745-303 (2008)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
HESS J1745-303 is an extended, unidentified VHE (very high energy) gamma-ray source discovered using HESS in the Galactic Plane Survey. Since no obvious counterpart has previously been found in...
Exploring a SNR/Molecular Cloud Association Within HESS J1745-303 (2008)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
HESS J1745-303 is an extended, unidentified VHE (very high energy) gamma-ray source discovered using HESS in the Galactic Plane Survey. Since no obvious counterpart has previously been found in...
Exploring a SNR/Molecular Cloud Association Within HESS J1745-303 (2008)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
HESS J1745-303 is an extended, unidentified VHE (very high energy) gamma-ray source discovered using HESS in the Galactic Plane Survey. Since no obvious counterpart has previously been found in...
An unusually bright and long outburst of Cygnus X-1 observed with INTEGRAL (2008)
Malzac, J., Lubinski, P., Zdziarski, A. A., Bel, M. Cadolle, Turler, M., Laurent, P.
We present INTEGRAL light curves and spectra of the black-hole binary Cyg X-1 during a bright event that occured in 2006 September, and which was simultaneous with a detection at 0.1-1 TeV energies...
A classification of the X-ray and radio states of Cyg X-3 and their long-term correlations (2008)
Szostek, A., Zdziarski, A. A., McCollough, M. L.
We present a detailed classification of the X-ray states of Cyg X-3 based on the spectral shape and a new classification of the radio states based on the long-term correlated behaviour of the radio...
Upper Limits from HESS active galactic nuclei Observations in 2005-2007 (2008)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
AIMS: Very high energy (VHE; E>100 GeV) gamma-ray studies were performed for 18 active galactic nuclei (AGN) from a variety of AGN classes. METHODS: VHE observations of a sample of 14 AGN, considered...
Upper Limits from HESS active galactic nuclei Observations in 2005-2007 (2008)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
AIMS: Very high energy (VHE; E>100 GeV) gamma-ray studies were performed for 18 active galactic nuclei (AGN) from a variety of AGN classes. METHODS: VHE observations of a sample of 14 AGN, considered...
Damped harmonic oscillator interpretation of the soft-state power spectra of Cyg X-1 (2008)
We develop a model of an accretion disc in which the variability induced at a given radius is governed by a damped harmonic oscillator at the corresponding epicyclic frequency. That variability...
Upper Limits from HESS active galactic nuclei Observations in 2005-2007 (2008)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
AIMS: Very high energy (VHE; E>100 GeV) gamma-ray studies were performed for 18 active galactic nuclei (AGN) from a variety of AGN classes. METHODS: VHE observations of a sample of 14 AGN, considered...
A compact pulsar wind nebula model of the gamma-ray loud binary LS I +61 303 (2008)
Zdziarski, A. A., Neronov, A., Chernyakova, M.
We study a model of of the binary system LS I +61 303 in which its radio to TeV emission is due to interaction of a relativistic wind from a pulsar with the wind from a Be star. The fast polar wind...
HESS very-high-energy gamma-ray sources without identified counterparts (2007)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
Context.The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV-100 TeV) provides a direct view of the parent population of ultra-relativistic particles found in astrophysical...
HESS very-high-energy gamma-ray sources without identified counterparts (2007)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
Context.The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV-100 TeV) provides a direct view of the parent population of ultra-relativistic particles found in astrophysical...
HESS very-high-energy gamma-ray sources without identified counterparts (2007)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
Context.The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV-100 TeV) provides a direct view of the parent population of ultra-relativistic particles found in astrophysical...
Effects of the stellar wind on X-ray spectra of Cygnus X-3 (2007)
We study X-ray spectra of Cyg X-3 from BeppoSAX, taking into account absorption and emission in the strong stellar wind of its companion. We find the intrinsic X-ray spectra are well modelled by disc...
Discovery of VHE gamma-rays from the distant BL Lac 1ES 0347-121 (2007)
Aharonian, F., Akhperjanian, A.G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
Aims: Our aim is to study the production mechanism for very-high-energy (VHE; >100GeV) gamma-rays in distant active galactic nuclei (AGN) and use the observed VHE spectrum to derive limits on the...
Discovery of VHE $\gamma$-rays from the distant BL Lacertae 1ES 0347-121 (2007)
Aharonian, F., Akhperjanian, A. G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
Aims.Our aim is to study the production mechanism for very-high-energy (VHE; >100 GeV) ?-rays in distant active galactic nuclei (AGN) and use the observed VHE spectrum to derive limits on the...
Discovery of VHE $\gamma$-rays from the distant BL Lacertae 1ES 0347-121 (2007)
Aharonian, F., Akhperjanian, A. G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
Aims.Our aim is to study the production mechanism for very-high-energy (VHE; >100 GeV) ?-rays in distant active galactic nuclei (AGN) and use the observed VHE spectrum to derive limits on the...
Discovery of VHE $\gamma$-rays from the distant BL Lacertae 1ES 0347-121 (2007)
Aharonian, F., Akhperjanian, A. G., Bazer-Bachi, A.R., Behera, B., Beilicke, M., ...
Aims.Our aim is to study the production mechanism for very-high-energy (VHE; >100 GeV) ?-rays in distant active galactic nuclei (AGN) and use the observed VHE spectrum to derive limits on the...
The nature of the hard state of Cygnus X-3 (2007)
Hjalmarsdotter, L., Zdziarski, A. A., Larsson, S., Beckmann, V., McCollough, M., Hannikainen, D. C., ...
The X-ray binary Cygnus X-3 is a highly variable X-ray source that displays a wide range of observed spectral states. One of the main states is significantly harder than the others, peaking at ~ 20...
Ibragimov, A., Zdziarski, A. A., Poutanen, J.
We study theoretical interpretations of the 150-d (superorbital) modulation observed in X-ray and radio emission of Cyg X-1 in the framework of models connecting this phenomenon to precession....
The superorbital variability and triple nature of the X-ray source 4U 1820-303 (2007)
Zdziarski, A. A., Wen, L., Gierlinski, M.
We perform a comprehensive analysis of the superorbital modulation in the ultracompact X-ray source 4U 1820-303, consisting of a white dwarf accreting onto a neutron star. Based on RXTE data, we...
Dependence of the orbital modulation of X-rays from 4U 1820-303 on the accretion rate (2007)
Zdziarski, A. A., Gierlinski, M., Wen, L., Kostrzewa, Z.
We report the discovery, using RXTE data, of a dependence of the X-ray orbital modulation depth on the X-ray spectral state in the ultracompact atoll binary \source. This state (measured by us by the...
Dependence of the orbital modulation of X-rays from 4U 1820-303 on the accretion rate (2007)
Zdziarski, A. A., Gierlin'ski, M., Wen, L., Kostrzewa, Z.
We report the discovery, using RXTE data, of a dependence of the X-ray orbital modulation depth on the X-ray spectral state in the ultracompact atoll binary \source. This state (measured by us by the...
The superorbital variability and triple nature of the X-ray source 4U 1820-303 (2007)
Zdziarski, A. A., Gierlin'ski, M., Wen, L.
We perform a comprehensive analysis of the superorbital modulation in the ultracompact X-ray source 4U 1820-303, consisting of a white dwarf accreting onto a neutron star. Based on RXTE data, we...
Discovery of VHE gamma-rays from the distant BL Lacertae 1ES0347-121 (2007)
Aharonian, F., Akhperjanian, A. G., De Almeida, U. B., Bazer-Bachi, A. R., Behera, B., Beilicke, M., ...
New constraints on the mid-IR EBL from the HESS discovery of VHE gamma-rays from 1ES 0229+200 (2007)
Aharonian, F., Akhperjanian, A. G., De Almeida, U. B., Bazer-Bachi, A. R., Behera, B., Beilicke, M., ...
An exceptional very high energy gamma-ray flare of PKS 2155-304 (2007)
Aharonian, F., Akhperjanian, A. G., Bazer-Bachi, A. R., Behera, B., Beilicke, M., Benbow, W., ...
Jet radio emission in Cygnus X-1 and its orbital modulation (2006)
We present results of our detailed theoretical study of the observed orbital modulation of the radio emission in Cyg X-1. The modulation occurs due to free-free absorption in the wind from the...
Pottschmidt, K, Chernyakova, M, Zdziarski, A A, Lubinski, P, Smith, D M, Bezayiff, N
The Galactic Center black hole candidate (BHC) GRS 1758-258 has been observed extensively within INTEGRAL's Galactic Center Deep Exposure (GCDE) program in 2003 and 2004, while also being monitored...
The broad-band spectrum of Cygnus X-1 measured by INTEGRAL (2006)
Cadolle Bel, M., Sizun, P., Goldwurm, A., Rodriguez, J., Laurent, P., Zdziarski, A.A., ...
The INTEGRAL satellite extensively observed the black hole binary Cygnus X-1 from 2002 November to 2004 November during calibration, open time and core program (Galactic Plane Scan) observations....
Spectral states of the X-ray binary IGR J17091--3624 observed by INTEGRAL and RXTE (2006)
Capitanio, F., Bazzano, A., Ubertini, P., Zdziarski, A. A., Bird, A. J., De Cesare, G., ...
IGR J17091-3624 was discovered in 2003 April by INTEGRAL/IBIS during its Galactic Centre Deep Exposure programme. The source was initially detectable only in the 40--100 keV range, but after two days...
The broad-band spectrum of Cygnus X-1 measured by INTEGRAL (2006)
Cadolle Bel, M., Sizun, P., Goldwurm, A., Rodriguez, J., Laurent, P., Zdziarski, A.A., ...
The INTEGRAL satellite extensively observed the black hole binary Cygnus X-1 from 2002 November to 2004 November during calibration, open time and core program (Galactic Plane Scan) observations....
The broad-band spectrum of Cygnus X-1 measured by INTEGRAL (2006)
Cadolle Bel, M., Sizun, P., Goldwurm, A., Rodriguez, J., Laurent, P., Zdziarski, A.A., ...
The INTEGRAL satellite extensively observed the black hole binary Cygnus X-1 from 2002 November to 2004 November during calibration, open time and core program (Galactic Plane Scan) observations....
INTEGRAL and RXTE power spectra of Cygnus X-1 (2006)
Pottschmidt, K., Wilms, J., Nowak, M. A., Larsson, S., Zdziarski, A. A., Pooley, G. G.
The broad-band spectrum of Cygnus X-1 measured by INTEGRAL (2005)
Bel, M. Cadolle, Sizun, P., Goldwurm, A., Rodriguez, J., Laurent, P., Zdziarski, A. A., ...
The INTEGRAL satellite extensively observed the black hole binary Cygnus X-1 from 2002 November to 2004 November during calibration, open time and core program (Galactic Plane Scan) observations....
Pottschmidt, K., Chernyakova, M., Zdziarski, A. A., Lubinski, P., Smith, D. M., Bezayiff, N.
The Galactic Center black hole candidate (BHC) GRS 1758-258 has been observed extensively within INTEGRAL's Galactic Center Deep Exposure (GCDE) program in 2003 and 2004, while also being monitored...
The High Energy Spectrum of NGC 4151 (2005)
Beckmann, V., Shrader, C. R., Gehrels, N., Soldi, S., Lubinski, P., Zdziarski, A. A., ...
We present the first INTEGRAL observations of the type 1.5 Seyfert galaxy NGC 4151. Combining several INTEGRAL observations performed during 2003, totaling about 400 ks of exposure time, allows us to...
INTEGRAL & RXTE Power Spectra of Cygnus X-1 (2005)
Pottschmidt, K., Wilms, J., Nowak, M. A., Larsson, S., Zdziarski, A. A., Pooley, G. G.
We evaluate 0.03-20 Hz power spectra of the bright black hole binary Cyg X-1 obtained from non-deconvolved INTEGRAL-ISGRI event data. The ISGRI power spectra are compared to contemporary RXTE-PCA...
Hannikainen, D. C., Rodriguez, J., Vilhu, O., Hjalmarsdotter, L., Zdziarski, A. A., Belloni, T., ...
We report on the analysis of 100 ks INTEGRAL observations of the Galactic microquasar GRS 1915+105. We focus on INTEGRAL Revolution number 48 when the source was found to exhibit a new type of...
The transient hard X-ray tail of GX 17+2: new BeppoSAX results (2005)
Farinelli, R., Frontera, F., Zdziarski, A. A., Stella, L., Zhang, S. N., ...
We report on results of two BeppoSAX observations of the Z source GX 17+2. In both cases the source is in the horizontal branch of the colour-intensity diagram. The persistent continuum can be fit by...
The transient hard X-ray tail of GX 17+2: New BeppoSAX results (2005)
Farinelli, R., Frontera, F., Zdziarski, A.A., Stella, L., Zhang, S.N., Klis, M. Van Der, ...
We report on results of two BeppoSAX observations of the Z source GX 17+2. In both cases the source is in the horizontal branch of the colour-intensity diagram. The persistent continuum can be fit by...
3-200 keV spectral states and variability of the INTEGRAL black hole binary IGR J17464-3213 (2005)
Capitanio, F., Ubertini, P., Bazzano, A., Kretschmar, P., Zdziarski, A. A., Joinet, A., ...
Broad-band spectra of Cygnus X-1 and correlations between spectral characteristics (2005)
Ibragimov, A., Poutanen, J., Gilfanov, M., Zdziarski, A. A., Shrader, C. R.
A study of spectra of Cyg X-3 observed by BeppoSAX (2004)
We model the ~1-200 keV spectra of Cygnus X-3 observed by BeppoSAX. The continuum, modeled by Comptonization in a hybrid plasma, is modified by the strongly ionized plasma of the stellar wind of the...
3-200 keV spectral states and variability of the INTEGRAL Black Hole binary IGR J17464-3213 (2004)
Capitanio, F., Ubertini, P., Bazzano, A., Kretschmar, P., Zdziarski, A. A., Joinet, A., ...
On March 2003, IBIS, the gamma-ray imager on board the INTEGRAL satellite, detected an outburst from a new source, IGR J17464-3213, that turned out to be a HEAO-1 transient, H1743-322. In this paper...
1E 1740.7-2942: temporal and spectral evolution from INTEGRAL and RXTE observations (2004)
Del Santo, M., Bazzano, A., Zdziarski, A. A., Smith, D. M., Bezayiff, N., Farinelli, R., ...
We present results of the monitoring of the black hole candidate 1E 1740.7-2942 with INTEGRAL, in combination with simultaneous observations by RXTE. We concentrate on broad-band spectra from...
The INTEGRAL LMXRB Monitoring Programme (2004)
Paizis, A., Courvoisier, T. J. -L., Vilhu, O., Chernyakova, M., Tikkanen, T., Bazzano, A., ...
Our collaboration is responsible for the study of a sample of 72 low mass X-ray binaries (LMXRB) using the INTEGRAL Core Programme data. In this paper we describe the monitoring programme we have...
GRS 1915+105: The first three months with INTEGRAL (2004)
Hannikainen, D. C., Vilhu, O., Rodriguez, J., Westergaard, N. J., Shaw, S., Pooley, G. G., ...
GRS 1915+105 is being observed as part of an Open Time monitoring program with INTEGRAL. Three out of six observations from the monitoring program are presented here, in addition to data obtained...
INTEGRAL Observations of Cygnus X-3 (2004)
Hjalmarsdotter, L., Zdziarski, A. A., Paizis, A., Beckmann, V., Vilhu, O.
The peculiar X-ray binary Cygnus X-3 has been observed on several occasions with the X/gamma-ray instruments on board INTEGRAL. We have collected data from available public and Galactic Plane Scan...
The sky behind our galaxy as seen by IBIS on INTEGRAL (2004)
Bassani, L., Malizia, A., Stephen, J. B., Gianotti, F., Schiavone, F., Bazzano, A., ...
During the Core Programme, INTEGRAL has surveyed a large portion of the sky (around 9000 square degrees); although INTEGRAL is not optimized for extra-galactic studies its observations have...
A study of RXTE and BeppoSAX observations of Cyg X-3 (2004)
We present an analysis of Cyg X-3 data from RXTE/PCA,HEXTE and ASM, supplemented by a selected spectrum from BeppoSAX. We fit the PCA/HEXTE spectra from 1996-2000 by a model including hybrid...
INTEGRAL-RXTE observations of Cygnus X-1 (2004)
Pottschmidt, K., Wilms, J., Nowak, M. A., Dubath, P., Kreykenbohm, I., Gleissner, T., ...
INTEGRAL/RXTE observations of Cygnus X-1 (2004)
Wilms, J., Pottschmidt, K., Nowak, M. A., Chernyakova, M., Rodriguez, J., Zdziarski, A. A., ...
Radiative processes, spectral states and variability of black-hole binaries. (2004)
Zdziarski, A. A., Gierliński, M.
We review radiative processes responsible for X-ray emission in hard(low) and soft (high) spectral states of black-hole binaries. The main process in the hard state appears to be scattering of...
First INTEGRAL observations of GRS 1915+105 (2003)
Hannikainen, D. C., Vilhu, O., Rodriguez, J., Brandt, S., Westergaard, N. J., Lund, N., ...
We present data from the first of six monitoring Open Time observations of GRS 1915+105 undertaken with the orbiting INTEGRAL satellite. The source was clearly detected with all three X-ray and...
IBIS preliminary results on Cygnus X-1 spectral and temporal characteristics (2003)
Bazzano, A., Bird, A. J., Capitanio, F., Del Santo, M., Ubertini, P., Zdziarski, A. A., ...
We report preliminary results of a broadband spectral and temporal study of the black-hole binary Cyg X-1 performed with the IBIS telescope. Cyg X-1 was the first pointed celestial target of IBIS...
Simultaneous multi-wavelength observations of GRS 1915+105 (2003)
Fuchs, Yael, Rodriguez, J., Mirabel, I. F., Chaty, S., Ribo, M., Dhawan, V., ...
We present the result of multi-wavelength observations of the microquasar GRS 1915+105 in a plateau state with a luminosity of ~7.5x10^{38) erg s-1 (~40% L_Edd), conducted simultaneously with the...
First INTEGRAL observations of Cygnus X-3 (2003)
Vilhu, O., Hjalmarsdotter, L., Zdziarski, A. A., Paizis, A., McCollough, M. L., Beckmann, V., ...
We present the first INTEGRAL results on Cyg X-3 from the PV phase observations of the Cygnus region. The source was clearly detected by the JEM-X, ISGRI and SPI detectors. The INTEGRAL observations...
Simultaneous observations of the quasar 3C 273 with INTEGRAL, XMM-Newton and RXTE (2003)
Courvoisier, T. J. -L., Beckmann, V., Bourban, G., Chenevez, J., Chernyakova, M., Deluit, S., ...
INTEGRAL has observed the bright quasar 3C 273 on 3 epochs in January 2003 as one of the first observations of the open programme. The observation on January 5 was simultaneous with RXTE and...
First INTEGRAL Observations of Eight Persistent Neutron Star Low Mass X-ray Binaries (2003)
Paizis, A., Beckmann, V., Courvoisier, T. J. -L., Vilhu, O., Lutovinov, A., Ebisawa, K., ...
Early results from the INTEGRAL Core Program, for a sample of eight persistently bright neutron star low mass X-ray binaries in the energy range from 5 keV to 200 keV are presented. It is shown that...
The INTEGRAL Science Data Centre (ISDC) (2003)
Courvoisier, T. J. -L., Walter, R., Beckmann, V., Dean, A. J., Dubath, P., Hudec, R., ...
The INTEGRAL Science Data Centre (ISDC) provides the INTEGRAL data and means to analyse them to the scientific community. The ISDC runs a gamma ray burst alert system that provides the position of...
Frontera, F., Amati, L., Zdziarski, A. A., Belloni, T., Del Sordo, S., Masetti, N., ...
XTE J1118+480 is a well established black hole candidate with a mass estimate in the range from 7 to 10 solar masses. With BeppoSAX we observed the source 4 times, from April to December 2000....