Search Publications
Galaxy evolution by color-log(n) type since redshift unity in the Hubble Ultra Deep Field
Cameron, E.; Driver, S. P.
Aims: We explore the use of the color-log(n) (where n is the global Sérsic index) plane as a tool for subdividing the galaxy population in a physically-motivated manner out to redshift unity. We thereby aim to quantify surface brightness evolution by color-log(n) type, accounting separately for the specific selection and measurement biases against…
Constraints on the kinematics of the 44Ti ejecta of Cassiopeia A from INTEGRAL/SPI
Knödlseder, J.; Decourchelle, A.; Vink, J. +2 more
Context: The medium-lived 44Ti isotope is synthesised by explosive Si-burning in core-collapse supernovae. It is extremely sensitive to the dynamics of the explosion and therefore can be used to indirectly probe the explosion scenario. The young supernova remnant Cassiopeia A is to date the only source of gamma-ray lines from 44
An XMM-Newton view of the dipping low-mass X-ray binary XTE J1710-281
Boirin, L.; Younes, G.; Sabra, B.
Context: Studying the spectral changes during the dips exhibited by almost edge-on, low-mass X-ray binaries (LMXBs) is a powerful means of probing the structure of accretion disks. The XMM-Newton, Chandra, or Suzaku discovery of absorption lines from Fe xxv and other highly-ionized species in many dippers has revealed a highly-ionized atmosphere a…
Non-thermal emission in the core of Perseus: results from a long XMM-Newton observation
Molendi, S.; Gastaldello, F.
We employ a long XMM-Newton observation of the core of the Perseus cluster to validate claims of a non-thermal component discovered with Chandra. From a meticulous analysis of our dataset, which includes a detailed treatment of systematic errors, we find the 2-10 keV surface brightness of the non-thermal component to be less than about 5 × 10…
The environment of the fast rotating star Achernar. II. Thermal infrared interferometry with VLTI/MIDI
Meilland, A.; Kervella, P.; Domiciano de Souza, A. +3 more
Context: As is the case of several other Be stars, Achernar is surrounded by an envelope, recently detected by near-IR interferometry.
Aims: We search for the signature of circumstellar emission at distances of a few stellar radii from Achernar, in the thermal IR domain.
Methods: We obtained interferometric observations on three VLTI basel…
Redshifts and lens profile for the double quasar QJ 0158-4325
Kneib, J. -P.; Faure, C.; Alloin, D. +5 more
Aims: We report on the redshift of the lensing galaxy and of the quasar QJ 0158-4325 and on the lens model of the system.
Methods: A deep VLT/FORS2 spectrum and HST/NICMOS-F160W images are deconvolved. From the images we derive the light profile of the lensing galaxy and an accurate relative astrometry for the system. In addition we measure th…
Coronal current sheet signatures during the 17 May 2002 CME-flare
Landini, F.; Poletto, G.; Aurass, H.
Context: The relation between current sheets (CSs) associated with flares, revealed by characteristic radio signatures, and current sheets associated with coronal mass ejections (CMEs), detected in coronal ultraviolet (UV) and white light data, has not been analyzed, yet.
Aims: We aim at establishing the relationship between CSs associated wit…
Photometric and spectroscopic investigation of 2867 Steins, target of the Rosetta mission. Ground-based results prior to the Rosetta fly-by
Barucci, M. A.; Fornasier, S.; Dotto, E. +8 more
Context: Rosetta is the cornerstone mission of ESA devoted to the study of minor bodies of the Solar System. During its journey to the comet 67P Churyumov-Gerasimenko, the main target, Rosetta also investigates two main belt asteroids, 2867 Steins (fly-by in September 2008) and 21 Lutetia (fly-by in July 2010).
Aims: In Spring 2008, we perform…
The molecular environment of the massive star forming region NGC 2024: Multi CO transition analysis
Emprechtinger, M.; Stutzki, J.; Güsten, R. +10 more
Context: Sites of massive star formation have complex internal structures. Local heating by young stars and kinematic processes, such as outflows and stellar winds, generate large temperature and velocity gradients. Complex cloud structures lead to intricate emission line shapes. CO lines from high mass star forming regions are rarely Gaussian and…
Relating basic properties of bright early-type dwarf galaxies to their location in Abell 901/902
Heymans, C.; Gray, M. E.; Wolf, C. +21 more
We present a study of the population of bright early-type dwarf galaxies in the multiple-cluster system Abell 901/902. We use data from the STAGES survey and COMBO-17 to investigate the relation between the color and structural properties of the dwarfs and their location in the cluster. The definition of the dwarf sample is based on the central su…