Search Publications
UltraVISTA: a new ultra-deep near-infrared survey in COSMOS
Sutherland, W.; Milvang-Jensen, B.; Fynbo, J. P. U. +18 more
In this paper we describe the first data release of the UltraVISTA near-infrared imaging survey of the COSMOS field. We summarise the key goals and design of the survey and provide a detailed description of our data reduction techniques. We provide stacked, sky-subtracted images in YJHKs and narrow-band filters constructed from data col…
Present-day cosmic abundances. A comprehensive study of nearby early B-type stars and implications for stellar and Galactic evolution and interstellar dust models
Przybilla, N.; Nieva, M. -F.
Context. Early B-type stars are ideal indicators for present-day cosmic abundances since they preserve their pristine abundances and typically do not migrate far beyond their birth environments over their short lifetimes, in contrast to older stars like the Sun. They are also unaffected by depletion onto dust grains, unlike the cold/warm interstel…
The ACS survey of Galactic globular clusters. XII. Photometric binaries along the main sequence
Moretti, A.; Anderson, J.; Milone, A. P. +15 more
Context. The fraction of binary stars is an important ingredient to interpret globular cluster dynamical evolution and their stellar population.
Aims: We investigate the properties of main-sequence binaries measured in a uniform photometric sample of 59 Galactic globular clusters that were observed by HST WFC/ACS as a part of the Globular Clu…
Cluster-formation in the Rosette molecular cloud at the junctions of filaments
Hill, T.; André, Ph.; Arzoumanian, D. +31 more
Aims: For many years feedback processes generated by OB-stars in molecular clouds, including expanding ionization fronts, stellar winds, or UV-radiation, have been proposed to trigger subsequent star formation. However, hydrodynamic models including radiation and gravity show that UV-illumination has little or no impact on the global dynamica…
Differential emission measures from the regularized inversion of Hinode and SDO data
Hannah, I. G.; Kontar, E. P.
Aims: To demonstrate the capabilities of regularized inversion to recover differential emission measures (DEMs) from multi-wavelength observations provided by telescopes such as Hinode and SDO.
Methods: We develop and apply an enhanced regularization algorithm, used in RHESSI X-ray spectral analysis, to constrain the ill-posed inverse pr…
The mean star formation rate of X-ray selected active galaxies and its evolution from z ~ 2.5: results from PEP-Herschel
Berta, S.; Magnelli, B.; Nordon, R. +37 more
We study relationships between star-formation rate (SFR) and the accretion luminosity and nuclear obscuration of X-ray selected active galactic nuclei (AGNs) using a combination of deep far-infrared (FIR) and X-ray data in three key extragalactic survey fields (GOODS-South, GOODS-North and COSMOS), as part of the PACS Evolutionary Probe (PEP) prog…
A Herschel view of the far-infrared properties of submillimetre galaxies
Smail, I.; Berta, S.; Magnelli, B. +48 more
We study a sample of 61submillimetre galaxies (SMGs) selected from ground-based surveys, with known spectroscopic redshifts and observed with the Herschel Space Observatory as part of the PACS Evolutionary Probe (PEP) and the Herschel Multi-tiered Extragalactic Survey (HerMES) guaranteed time key programmes. Our study makes use of the broad far-in…
Rotational velocities of A-type stars. IV. Evolution of rotational velocities
Royer, F.; Zorec, J.
Context. In previous works of this series, we have shown that late B- and early A-type stars have genuine bimodal distributions of rotational velocities and that late A-type stars lack slow rotators. The distributions of the surface angular velocity ratio Ω/Ωcrit (Ωcrit is the critical angular velocity) have peculiar shapes a…
Water in star-forming regions with Herschel (WISH). II. Evolution of 557 GHz 110-101 emission in low-mass protostars
Liseau, R.; van Dishoeck, E. F.; Bergin, E. A. +22 more
Context. Water is a key tracer of dynamics and chemistry in low-mass star-forming regions, but spectrally resolved observations have so far been limited in sensitivity and angular resolution, and only data from the brightest low-mass protostars have been published.
Aims: The first systematic survey of spectrally resolved water emission in 29 …
The warm gas atmosphere of the HD 100546 disk seen by Herschel. Evidence of a gas-rich, carbon-poor atmosphere?
van Dishoeck, E. F.; Bruderer, S.; Herczeg, G. J. +1 more
Context. With the Herschel Space Observatory, lines of simple molecules (C+, O, and high-J lines of CO, Jup ≳ 14) have been observed in the atmosphere of protoplanetary disks. When combined with ground-based data on [C i], all principle forms of carbon can be studied. These data allow us to test model predictions for the main…