Search Publications
Gravitational lensing and dynamics in SL2S J02140-0535: probing the mass out to large radius
Richard, J.; Cabanac, R.; Limousin, M. +3 more
Context. Studying the density profiles of galaxy groups offers an important insight into the formation and evolution of the structures in the universe, since galaxy groups bridge the gap between single galaxies and massive clusters.
Aims: We aim to probe the mass of
No quantum gravity signature from the farthest quasars
Della Valle, M.; Gilmozzi, R.; Tamburini, F. +1 more
Context. Strings and other alternative theories describing the quantum properties of space-time suggest that space-time could present a foamy structure and also that, in certain cases, quantum gravity (QG) may manifest at energies much below the Planck scale. One of the observable effects could be the degradation of the diffraction images of dista…
X-ray spectroscopy of MXB 1728-34 with XMM-Newton
Robba, N. R.; Dauser, T.; Wilms, J. +8 more
We analyzed an XMM-Newton observation of the low-mass X-ray binary and atoll source MXB 1728-34. The source was in a low-luminosity state during the XMM-Newton observation, corresponding to a bolometric X-ray luminosity of 5 × 1036 d5.1 kpc2 erg s-1. The 1-11 keV X-ray spectrum of the source, obtained co…
The low-mass initial mass function in the Orion nebula cluster based on HST/NICMOS III imaging
Robberto, M.; Andersen, M.; Meyer, M. R. +2 more
We present deep HST/NICMOS Camera 3 F110W and F160W imaging of a 26' × 33', corresponding to 3.1 pc × 3.8 pc, non-contiguous field towards the Orion nebula cluster (ONC). The main aim is to determine the ratio of low-mass stars to brown dwarfs for the cluster as a function of radius out to a radial distance of 1.5 pc. The sensitivity of the data o…
INTEGRAL, Swift, and RXTE observations of the 518 Hz accreting transient pulsar Swift J1749.4-2807
Campana, S.; Stella, L.; Belloni, T. +7 more
Context. The burst-only source Swift J1749.4-2807 was discovered in a high X-ray-active state, during an INTEGRAL observations of the Galactic bulge on 2010 April 10. Pulsations at 518 Hz were discovered in the RXTE data, confirming previous suggestions of possible associations between burst-only sources and accreting millisecond X-ray pulsars. Th…
67P/Churyumov-Gerasimenko activity evolution during its last perihelion before the Rosetta encounter
Lara, L. M.; Rodrigo, R.; Ip, W. -H. +1 more
Context. The comet 67P/Churyumov-Gerasimenko, target of the Rosetta Mission (ESA) was monitored from January to April 2009 during its last perihelion passage before the Rosetta spacecraft encounters the comet nucleus in May 2014. Photometric data were obtained only from January 25 to March 19, 2009 and they were used to monitor the comet gas and d…
On the Lx - L6 µm ratio as a diagnostic for Compton-thick AGN
Vignali, C.; Gilli, R.; Ranalli, P. +6 more
As the mid-IR luminosity represents a good isotropic proxy of the AGN power, a low X-ray to mid-IR luminosity ratio is often claimed to be a reliable indicator of Compton-thick AGN. We assess the efficiency of the X-ray to mid-IR luminosity ratio diagnostic by examining the 12 µm IRAS AGN sample (intrinsic L2-10 keV > 1042…
A2163: Merger events in the hottest Abell galaxy cluster. II. Subcluster accretion with galaxy-gas separation
Arnaud, M.; Pratt, G. W.; Bourdin, H. +7 more
Located at z = 0.203, A2163 is a rich galaxy cluster with an intra-cluster medium (ICM) that exhibits extraordinary properties, including an exceptionally high X-ray luminosity, average temperature, and a powerful and extended radio halo. The irregular and complex morphology of its gas and galaxy structure suggests that this cluster has recently u…
First results of Herschel-SPIRE observations of Titan
Hartogh, P.; Lellouch, E.; Moreno, R. +4 more
We investigate the composition of Titan's stratosphere from high-resolution submillimetric observations performed with the SPIRE instrument on the Herschel satellite. From the flux density spectrum measured in the 20 - 52 cm-1 interval at an apodized resolution of 0.08 cm-1, we determine the stratospheric abundances of CH
Multiwavelength campaign on Mrk 509. V. Chandra-LETGS observation of the ionized absorber
Kaastra, J. S.; Kriss, G. A.; Arav, N. +11 more
Context. We present here the results of a 180 ks Chandra-LETGS observation as part of a large multi-wavelength campaign on Mrk 509.
Aims: We study the warm absorber in Mrk 509 and use the data from a simultaneous HST-COS observation in order to assess whether the gas responsible for the UV and X-ray absorption are the same.
Methods: We a…