Search Publications
The innermost region of AGN tori: implications from the HST/NICMOS type 1 point sources and near-IR reverberation
Hönig, S. F.; Kishimoto, M.; Weigelt, G. +1 more
Spatially resolving the innermost region of the putative torus-like structure in an active galactic nucleus (AGN) is one of the main goals of high-spatial-resolution studies. This could be done in the near-IR observations of type 1 AGNs where we directly see the hottest dust grains in the torus. We discuss two critical issues in such studies. One …
Calibration of the galaxy cluster M{500}-Y{X} relation with XMM-Newton
Arnaud, M.; Pointecouteau, E.; Pratt, G. W.
The quantity Y_X, the product of the X-ray temperature TX and gas mass M_g, has recently been proposed as a robust low-scatter mass indicator for galaxy clusters. Using precise measurements from XMM-Newton data of a sample of 10 relaxed nearby clusters, spanning a YX range of 1013-1015 M_⊙ keV, we invest…
INTEGRAL/IBIS all-sky survey in hard X-rays
Sunyaev, R.; Krivonos, R.; Revnivtsev, M. +3 more
We present results of an all-sky hard X-ray survey based on almost four years of observations with the IBIS telescope onboard the INTEGRAL observatory. The dead time-corrected exposure of the survey is ~33 Ms. Approximately 12% and 80% of the sky has been covered to limiting fluxes lower than 1 and 5 mCrab, respectively. Our catalog of detected so…
Probing clumpy stellar winds with a neutron star
Walter, R.; Zurita Heras, J.
Context: INTEGRAL, the European Space Agency's γ-ray observatory, tripled the number of super-giant high-mass X-ray binaries (sgHMXB) known in the Galaxy by revealing absorbed and fast transient (SFXT) systems.
Aims: In these sources, quantitative constraints on the wind clumping of the massive stars could be obtained from the study of the har…
X-ray emission from T Tauri stars and the role of accretion: inferences from the XMM-Newton extended survey of the Taurus molecular cloud
Audard, M.; Güdel, M.; Briggs, K. R. +2 more
Context: T Tau stars display different X-ray properties depending on whether they are accreting (classical T Tau stars; CTTS) or not (weak-line T Tau stars; WTTS). X-ray properties may provide insight into the accretion process between disk and stellar surface.
Aims: We use data from the XMM-Newton Extended Survey of the Taurus molecular cloud…
The CFHTLS strong lensing legacy survey. I. Survey overview and T0002 release sample
Alard, C.; Gavazzi, R.; Fort, B. +10 more
Aims:We present data from the CFHTLS Strong Lensing Legacy Survey (SL2S). Due to the unsurpassed combined depth, area and image quality of the Canada-France-Hawaii Legacy Survey it is becoming possible to uncover a large, statistically well-defined sample of strong gravitational lenses which spans the dark halo mass spectrum predicted by the conco…
Six new candidate ultracompact X-ray binaries
in't Zand, J. J. M.; Jonker, P. G.; Markwardt, C. B.
Ultracompact X-ray binaries (UCXBs) appear able to sustain accretion onto the compact accretor at rates lower than in wider X-ray binaries. This may be understood by the smaller accretion disks in UCXBs: a lower X-ray luminosity suffices to keep a disk completely ionized through irradiation and, thus, keep the viscosity at a sufficiently high leve…
Polarisation studies of the prompt gamma-ray emission from GRB 041219a using the spectrometer aboard INTEGRAL
McGlynn, S.; McBreen, S.; Foley, S. +6 more
Context: Linear polarisation in gamma-ray burst prompt emission is an important diagnostic with the potential to significantly constrain models. The spectrometer aboard INTEGRAL, SPI, has the capability to detect the signature of polarised emission from a bright γ-ray source. GRB 041219a is the most intense burst localised by INTEGRAL with a fluen…
Discovery of a flux-related change of the cyclotron line energy in Hercules X-1
Klochkov, D.; Wilms, J.; Staubert, R. +5 more
Aims: We present the results of ten years of repeated measurements of the Cyclotron Resonance Scattering Feature (CRSF) in the spectrum of the binary X-ray pulsar
Hard X-ray luminosity function and absorption distribution of nearby AGN: INTEGRAL all-sky survey
Sunyaev, R.; Krivonos, R.; Revnivtsev, M. +2 more
Aims:We study the hard X-ray luminosity function and absorption distribution of local (z≲ 0.1) active galactic nuclei (AGN) and discuss the implications for AGN cosmological evolution and for the cosmic X-ray background (CXB).
Methods: We use the INTEGRAL all-sky hard X-ray survey to perform a statistical study of a representative sample of ne…