Search Publications
Size growth of red-sequence early-type galaxies in clusters in the last 10 Gyr
Andreon, S.; Dong, Hui; Raichoor, A.
We carried out a photometric and structural analysis in the rest-frame V band of a mass-selected (log M/M⊙> 10.7) sample of red-sequence galaxies in 14 galaxy clusters, 6 of which are at z> 1.45, namely JKCS041, IDCS J1426.5+3508, SpARCS104922.6+564032.5, SpARCSJ021524-034331, XDCPJ0044.0-2033, and SPT-CLJ2040-4451. To this end, w…
The SOPHIE search for northern extrasolar planets. VIII. Follow-up of ELODIE candidates: long-period brown-dwarf companions
Bouchy, F.; Moutou, C.; Queloz, D. +29 more
Long-period brown dwarf companions detected in radial velocity surveys are important targets for direct imaging and astrometry to calibrate the mass-luminosity relation of substellar objects. Through a 20-yr radial velocity monitoring of solar-type stars that began with ELODIE and was extended with SOPHIE spectrographs, giant exoplanets and brown …
The extinction and dust-to-gas structure of the planetary nebula NGC 7009 observed with MUSE
Walsh, J. R.; Barlow, M. J.; Monreal-Ibero, A. +3 more
Context. Dust plays a significant role in planetary nebulae. Dust ejected with the gas in the asymptotic giant branch (AGB) phase is subject to the harsh environment of the planetary nebula (PN) while the star is evolving towards a white dwarf. Dust surviving the PN phase contributes to the dust content of the interstellar medium.
Aims: The m…
An HST/COS legacy survey of intervening Si III absorption in the extended gaseous halos of low-redshift galaxies
Wakker, B. P.; Fechner, C.; Richter, P. +3 more
Aims: Doubly ionized silicon (Si III) is a powerful tracer of diffuse ionized gas inside and outside of galaxies. It can be observed in the local Universe in ultraviolet (UV) absorption against bright extragalactic background sources. We here present an extensive study of intervening Si III-selected absorbers and study the properties of the w…
The Lyman alpha reference sample. VI. Lyman alpha escape from the edge-on disk galaxy Mrk 1486
Verhamme, Anne; Cannon, John M.; Hayes, Matthew +16 more
Context. Recent numerical simulations suggest that the strength of the Lyman alpha (Lyα) line of star-forming disk galaxies strongly depends on the inclination at which they are observed: from edge-on to face-on, we expect to see a change from a strongly attenuated Lyα line to a strong Lyα emission line.
Aims: We aim to understand how a stron…
The gamma-ray emitting radio-loud narrow-line Seyfert 1 galaxy PKS 2004-447. I. The X-ray View
Gehrels, N.; Wilms, J.; Kadler, M. +11 more
As part of the TANAMI multiwavelength progam, we discuss new X-ray observations of the γ-ray and radio-loud narrow line Seyfert 1 galaxy (γ-NLS1) PKS 2004-447. The active galaxy is a member of a small sample of radio-loud NLS1s detected in γ-rays by the Fermi Large Area Telescope. It stands out for being the radio-loudest and the only southern-hem…
Pulsating hot O subdwarfs in ω Centauri: mapping a unique instability strip on the extreme horizontal branch
Dhillon, V. S.; Chayer, P.; Fontaine, G. +10 more
We present the results of an extensive survey for rapid pulsators among Extreme Horizontal Branch (EHB) stars in ω Cen. The observations performed consist of nearly 100 h of time-series photometry for several off-centre fields of the cluster, as well as low-resolution spectroscopy for a partially overlapping sample. We obtained photometry for some…
Nine new open clusters within 500 pc from the Sun
Goldman, Bertrand; Röser, Siegfried; Schilbach, Elena
Aims: One of the results of the Milky Way Star Clusters (MWSC) survey was the detection of a slight under-density of old (ca. 1 Gyr) clusters within the nearest kilo-parsec from the Sun. This under-density may be due to an ineffectiveness in the detection of larger structures with lower surface brightness. We report on our attempts to reveal …
X-ray analysis of the galaxy group UGC 03957 beyond R200 with Suzaku
Thölken, Sophia; Reiprich, Thomas H.; Lovisari, Lorenzo +1 more
Context. In the last few years, the outskirts of galaxy clusters have been studied in detail and the analyses have brought up interesting results such as indications of possible gas clumping and the breakdown of hydrostatic, thermal, and ionization equilibrium. These phenomena affect the entropy profiles of clusters, which often show deviations fr…
Highly ionized region surrounding SN Refsdal revealed by MUSE
Treu, T.; Grillo, C.; Balestra, I. +9 more
Supernova (SN) Refsdal is the first multiply imaged, highly magnified, and spatially resolved SN ever observed. The SN exploded in a highly magnified spiral galaxy at z = 1.49 behind the Frontier Fields cluster MACS1149, and provides a unique opportunity to study the environment of SNe at high z. We exploit the time delay between multiple images t…