Search Publications
The origin and evolution of the Peace Vallis fan system that drains to the Curiosity landing area, Gale Crater, Mars
Williams, Rebecca M. E.; Palucis, Marisa C.; Calef, Fred +7 more
The landing site for the Curiosity rover is located at the distal end of the Peace Vallis fan in Gale Crater. Peace Vallis fan covers 80 km2 and is fed by a 730 km2 catchment, which drains an upland plains area through a 15 km wide gap in the crater rim. Valley incision into accumulated debris delivered sediment through a rel…
On the determination of the spin and disc truncation of accreting black holes using X-ray reflection
Fabian, A. C.; Miller, J. M.; Reynolds, C. S. +4 more
We discuss the application of simple relativistically blurred X-ray reflection models to the determination of the spin and the inner radius of the disc in accreting black holes. Observationally, the nature of the corona is uncertain a priori, but a robust determination of the inner disc radius can be made when the disc emissivity index is tightly …
Class 0 Protostars in the Perseus Molecular Cloud: A Correlation Between the Youngest Protostars and the Dense Gas Distribution
Bernard, J. -P.; Hill, T.; White, G. J. +18 more
We use PACS and SPIRE continuum data at 160 µm, 250 µm, 350 µm, and 500 µm from the Herschel Gould Belt Survey to sample seven clumps in Perseus: B1, B1-E, B5, IC 348, L1448, L1455, and NGC 1333. Additionally, we identify and characterize the embedded Class 0 protostars using detections of compact Herschel sources at 70 &mi…
The VLT-FLAMES Tarantula Survey. XIV. The O-type stellar content of 30 Doradus
Lennon, D. J.; Simón-Díaz, S.; de Koter, A. +6 more
Detailed spectral classifications are presented for 352 O-B0 stars in the VLT-FLAMES Tarantula Survey ESO Large Programme, of which 213 O-type are judged of sufficiently high quality for further morphological analysis. Among them, six subcategories of special interest are distinguished. (1) Several new examples of the earliest spectral types O2-O3…
Dust in the diffuse interstellar medium. Extinction, emission, linear and circular polarisation
Siebenmorgen, R.; Bagnulo, S.; Voshchinnikov, N. V.
We present a model for the diffuse interstellar dust that explains the observed wavelength-dependence of extinction, emission, and the linear and circular polarisation of light. The model is set up with a small number of parameters. It consists of a mixture of amorphous carbon and silicate grains with sizes from the molecular domain of 0.5 up to a…
Secular- and merger-built bulges in barred galaxies
Corsini, E. M.; Aguerri, J. A. L.; Méndez-Abreu, J. +1 more
Context. Historically, galaxy bulges were thought to be single-component objects at the center of galaxies. However, this picture is now questioned since different bulge types with different formation paths, namely classical and pseudobulges, have been found coexisting within the same galaxy.
Aims: We study the incidence and nature of composi…
A new double radio relic in PSZ1 G096.89+24.17 and a radio relic mass-luminosity relation
Vazza, F.; van Weeren, R. J.; Bonafede, A. +3 more
Radio relics are diffuse synchrotron sources in galaxy clusters that are believed to trace large-scale shock waves. We have discovered a new double radio relic system in PSZ1 G096.89+24.17 (z = 0.3) and have carried out a full-polarization radio observation using the Westerbork Synthesis Radio Telescope at 1.4 GHz. The observation revealed the pre…
New distances to RAVE stars
Gilmore, G.; Watson, F.; Steinmetz, M. +16 more
Probability density functions (pdfs) are determined from new stellar parameters for the distance moduli of stars for which the RAdial Velocity Experiment (RAVE) has obtained spectra with S/N ≥ 10. Single-Gaussian fits to the pdf in distance modulus suffice for roughly half the stars, with most of the other half having satisfactory two-Gaussian rep…
Disk Radii and Grain Sizes in Herschel-resolved Debris Disks
Moór, Attila; Pawellek, Nicole; Ábrahám, Péter +5 more
The radii of debris disks and the sizes of their dust grains are important tracers of the planetesimal formation mechanisms and physical processes operating in these systems. Here we use a representative sample of 34 debris disks resolved in various Herschel Space Observatory (Herschel is an ESA space observatory with science instruments provided …
Planck 2013 results. XIV. Zodiacal emission
Kneissl, R.; Miville-Deschênes, M. -A.; Boulanger, F. +229 more
The Planck satellite provides a set of all-sky maps at nine frequencies from 30 GHz to 857 GHz. Planets, minor bodies, and diffuse interplanetary dust emission (IPD) are all observed. The IPD can be separated from Galactic and other emissions because Planck views a given point on the celestial sphere multiple times, through different columns of IP…