Search Publications
The 69 µm forsterite band in spectra of protoplanetary disks. Results from the Herschel DIGIT programme
Waters, L. B. F. M.; Dominik, C.; Henning, Th. +13 more
Context. We have analysed far-infrared spectra of 32 circumstellar disks around Herbig Ae/Be and T Tauri stars obtained within the Herschel key programme Dust, Ice and Gas in Time (DIGIT). The spectra were taken with the Photodetector Array Camera and Spectrometer (PACS) on board the Herschel Space Observatory. In this paper we focus on the detect…
Dynamics of the solar atmosphere above a pore with a light bridge
Heinzel, P.; Jurčák, J.; Berrilli, F. +3 more
Context. Solar pores are small sunspots lacking a penumbra that have a prevailing vertical magnetic-field component. They can include light bridges at places with locally reduced magnetic field. Like sunspots, they exhibit a wide range of oscillatory phenomena.
Aims: A large isolated pore with a light bridge (NOAA 11005) is studied to obtain …
OTS 44: Disk and accretion at the planetary border
Liu, Y.; Bayo, A.; Wolf, S. +4 more
We discover that the very low-mass brown dwarf OTS 44 (M9.5, ~12 MJup) has significant accretion and a substantial disk, which demonstrates that the processes that accompany canonical star formation occur down to a central mass of a few Jupiter masses. We discover in VLT/SINFONI spectra that OTS 44 has strong, broad, and variable Pa β e…
Protostars, multiplicity, and disk evolution in the Corona Australis region: a Herschel Gould Belt Study
Eiroa, C.; White, G. J.; Henning, T. +4 more
Context. The CrA region and the Coronet cluster form a nearby (138 pc), young (1-2 Myr) star-forming region that hosts a moderate population of Class I, II, and III objects.
Aims: We study the structure of the cluster and the properties of the protostars and protoplanetary disks in the region.
Methods: We present Herschel PACS photometry…
Observational evidence for dissociative shocks in the inner 100 AU of low-mass protostars using Herschel-HIFI
van Dishoeck, E. F.; Benz, A. O.; Bruderer, S. +3 more
Aims: Herschel-HIFI spectra of H2O towards low-mass protostars show a distinct velocity component not seen in observations from the ground of CO or other species. The aim is to characterise this component in terms of excitation conditions and physical origin.
Methods: A velocity component with an offset of ~10 km s-1
Discovery of the magnetic field in the pulsating B star β Cephei
Talavera, A.; Donati, J. -F.; Kaper, L. +17 more
Context. Although the star itself is not helium enriched, the periodicity and the variability in the UV wind lines of the pulsating B1 IV star β Cephei are similar to what is observed in magnetic helium-peculiar B stars, suggesting that β Cep is magnetic.
Aims: We searched for a magnetic field using high-resolution spectropolarimetry. From UV…
High-pressure, low-abundance water in bipolar outflows. Results from a Herschel-WISH survey
Liseau, R.; van Dishoeck, E. F.; Bachiller, R. +6 more
Context. Water is a potential tracer of outflow activity because it is heavily depleted in cold ambient gas and is copiously produced in shocks.
Aims: We present a survey of the water emission in a sample of more than 20 outflows from low-mass young stellar objects with the goal of characterizing the physical and chemical conditions of the em…
A non-pulsating neutron star in the supernova remnant HESS J1731-347/G353.6-0.7 with a carbon atmosphere
Werner, K.; Klochkov, D.; Santangelo, A. +3 more
Context. The central compact object (CCO) candidate in the center of the supernova remnant shell HESS J1731-347/G353.6-0.7 shows no pulsations and exhibits a blackbody-like X-ray spectrum. If the absence of pulsations is interpreted as evidence for the emitting surface area being the entire neutron star surface, the assumption of the measured flux…
Ionisation impact of high-mass stars on interstellar filaments. A Herschel study of the RCW 36 bipolar nebula in Vela C
Hill, T.; White, G. J.; André, Ph. +19 more
Context. Ionising stars reshape their original molecular cloud and impact star formation, leading to spectacular morphologies such as bipolar nebulae around H ii regions. Molecular clouds are structured in filaments where stars principally form, as revealed by the Herschel space observatory. The prominent southern hemisphere H ii region, RCW 36, i…
Importance of thermal reactivity for hexamethylenetetramine formation from simulated interstellar ices
Vinogradoff, V.; Duvernay, F.; Danger, G. +5 more
Context. Complex organic molecules are observed in a broad variety of astrophysical objects, but little is known about their formation mechanism. Laboratory simulations on interstellar ice analogues are therefore crucial for understanding the origin of these complex organic molecules. In this context, we focus on the thermal reactivity for the for…