Search Publications
The D/H ratio in the atmospheres of Uranus and Neptune from Herschel-PACS observations
Hartogh, P.; Lellouch, E.; de Graauw, T. +9 more
Herschel-PACS measurements of the rotational R(0) and R(1) HD lines in the atmospheres of Uranus and Neptune are analyzed to derive a D/H ratio with improved precision for the two planets. The derivation of the D/H ratio also includes previous measurements of the R(2) line with the Short Wavelength Spectrometer on board the Infrared Space Observat…
The redshift evolution of the distribution of star formation among dark matter halos as seen in the infrared
Daddi, Emanuele; Béthermin, Matthieu; Lagache, Guilaine +5 more
Recent studies have revealed a strong correlation between the star formation rate (SFR) and stellar mass of the majority of star-forming galaxies, the so-called star-forming main sequence. An empirical modeling approach (the 2-SFM framework) that distinguishes between the main sequence and rarer starburst galaxies is capable of reproducing most st…
MAXI J1659-152: the shortest orbital period black-hole transient in outburst
Díaz Trigo, M.; Parmar, A. N.; Belloni, T. +12 more
MAXI J1659-152 is a bright X-ray transient black-hole candidate binary system discovered in September 2010. We report here on MAXI, RXTE, Swift, and XMM-Newton observations during its 2010/2011 outburst. We find that during the first one and a half week of the outburst the X-ray light curves display drops in intensity at regular intervals, which w…
A detailed study of the radio-FIR correlation in NGC 6946 with Herschel-PACS/SPIRE from KINGFISH
Helou, G.; Roussel, H.; Murphy, E. J. +22 more
We derive the distribution of the synchrotron spectral index across NGC 6946 and investigate the correlation between the radio continuum (synchrotron) and far-infrared (FIR) emission using the KINGFISH Herschel-PACS and SPIRE data. The radio-FIR correlation is studied as a function of star formation rate, magnetic field strength, radiation field s…
Herschel/HIFI observations of [C II] and [13C II] in photon-dominated regions
Ossenkopf, V.; Lis, D. C.; Neufeld, D. A. +5 more
Context. Chemical fractionation reactions in the interstellar medium can result in molecular isotopologue abundance ratios that differ by many orders of magnitude from the isotopic abundance ratios. Understanding variations in the molecular abundance ratios through astronomical observations provides a new toolto sensitively probe the underlying ph…
Progenitors of supernova Ibc: a single Wolf-Rayet star as the possible progenitor of the SN Ib iPTF13bvn
Groh, Jose H.; Ekström, Sylvia; Georgy, Cyril
Core-collapse supernova (SN) explosions mark the end of the tumultuous life of massive stars. Determining the nature of their progenitors is a crucial step towards understanding the properties of SNe. Until recently, no progenitor has been directly detected for SN of type Ibc, which are believed to come from massive stars that lose their hydrogen …
Variation in dust properties in a dense filament of the Taurus molecular complex (L1506)
Abergel, A.; Juvela, M.; Ristorcelli, I. +6 more
Aims: We observed the L1506 filament, which is located in the Taurus molecular complex, with the Herschel PACS and SPIRE instruments. Our aim is to prove the variation in grain properties along the entire length of the filament. In particular, we want to determine above which gas density this variation arises and what changes in the grain opt…
Massive stars at low metallicity. Evolution and surface abundances of O dwarfs in the SMC
Bouret, J. -C.; Martins, F.; Hillier, D. J. +4 more
Aims: We aim to study the properties of massive stars at low metallicity, with an emphasis on their evolution, rotation, and surface abundances. We focus on O-type dwarfs in the Small Magellanic Cloud. These stars are expected to have weak winds that do not remove significant amounts of their initial angular momentum.
Methods: We analyze…
High-fidelity view of the structure and fragmentation of the high-mass, filamentary IRDC G11.11-0.12
Henning, T.; Kainulainen, J.; Stutz, A. +1 more
Star formation in molecular clouds is intimately linked to their internal mass distribution. We present an unprecedentedly detailed analysis of the column density structure of a high-mass, filamentary molecular cloud, namely IRDC G11.11-0.12 (G11). We use two novel column density mapping techniques: high-resolution (FWHM = 2″, or ~0.035 pc) dust e…
Why circumstellar disks are so faint in scattered light: the case of HD 100546
Dominik, C.; Min, M.; Schneider, G. +2 more
Context. Scattered light images of circumstellar disks play an important role in characterizing the planet forming environments around young stars. The characteristic size of the scattering dust grains can be estimated from the observed brightness asymmetry between the near and far side of the disk, for example using standard Mie theory. Such mode…