Search Publications
Low frequency radio observations of bi-directional electron beams in the solar corona
Gallagher, Peter T.; Carley, Eoin P.; Vilmer, Nicole +1 more
The radio signature of a shock travelling through the solar corona is known as a type II solar radio burst. In rare cases these bursts can exhibit a fine structure known as "herringbones", which are a direct indicator of particle acceleration occurring at the shock front. However, few studies have been performed on herringbones and the details of …
High spectral and spatial resolution observations of the PDR emission in the NGC 2023 reflection nebula with SOFIA and APEX
Okada, Y.; Güsten, R.; Requena-Torres, M. A. +3 more
We have mapped the NGC 2023 reflection nebula in [C ii] and CO(11-10) with the heterodyne receiver GREAT on SOFIA and obtained slightly smaller maps in 13CO(3-2), CO(3-2), CO(4-3), CO(6-5), and CO(7-6) with APEX in Chile. We use these data to probe the morphology, kinematics, and physical conditions of the C ii region, which is ionized …
Internal structure of spiral arms traced with [C II]: Unraveling the warm ionized medium, H I, and molecular emission lanes
Goldsmith, P. F.; Langer, W. D.; Pineda, J. L. +1 more
Context. The spiral arm tangencies are ideal lines of sight in which to determine the distribution of interstellar gas components in the spiral arms and study the influence of spiral density waves on the interarm gas in the Milky Way. [C II] emission in the tangencies delineates the warm ionized component and the photon-dominated regions and is th…
First detections of FS Canis Majoris stars in clusters. Evolutionary state as constrained by coeval massive stars
Najarro, F.; Davies, B.; de la Fuente, D. +2 more
Context. FS CMa stars are low-luminosity objects showing the B[e] phenomenon whose evolutionary state remains a puzzle. These stars are surrounded by compact disks of warm dust of unknown origin. Hitherto, membership of FS CMa stars to coeval populations has never been confirmed.
Aims: The discovery of low-luminosity line emitters in the youn…
A homogeneous analysis of disks around brown dwarfs
Liu, Y.; Bayo, A.; Wang, H. +2 more
We re-analyzed the Herschel/PACS data of a sample of 55 brown dwarfs (BDs) and very low mass stars with spectral types ranging from M5.5 to L0. We investigated the dependence of disk structure on the mass of the central object in the substellar regime based on a homogeneous analysis of Herschel data from flux density measurements to spectral energ…
What powers Lyα blobs?
Menten, K. M.; Omont, A.; Lagache, G. +14 more
Lyα blobs (LABs) are spatially extended Lyα nebulae seen at high redshift. The origin of Lyα emission in the LABs is still unclear and under debate. To study their heating mechanism(s), we present Australia Telescope Compact Array (ATCA) observations of the 20 cm radio emission and Herschel PACS and SPIRE measurements of the far-infrared (FIR) emi…
Alfvénic waves in polar spicules
Koutchmy, S.; Ahangarzadeh Maralani, A. R.; Tavabi, E. +2 more
Context. For investigating spicules from the photosphere to coronal heights, the new Hinode/SOT long series of high-resolution observations from space taken in CaII H line emission offers an improved way to look at their remarkable dynamical behavior using images free of seeing effects. They should be put in the context of the huge amount of alrea…
Infrared study of transitional disks in Ophiuchus with Herschel
André, Philippe; Ábrahám, Péter; Bouy, Hervé +7 more
Context. Observations of nearby star-forming regions with the Herschel Space Observatory complement our view of the protoplanetary disks in Ophiuchus with information about the outer disks.
Aims: The main goal of this project is to provide new far-infrared fluxes for the known disks in the core region of Ophiuchus and to identify potential tr…
Cassini ISS astrometry of the Saturnian satellites: Tethys, Dione, Rhea, Iapetus, and Phoebe 2004-2012
Cooper, N. J.; Lainey, V.; Murray, C. D. +1 more
Context. The Cassini spacecraft has been orbiting Saturn since 2004 and has returned images of satellites with an astrometric resolution as high as a few hundred meters per pixel.
Aims: We used the images taken by the Narrow Angle Camera (NAC) of the Image Science Subsystem (ISS) instrument on board Cassini, for the purpose of astrometry.
Location and sizes of forsterite grains in protoplanetary disks. Interpretation from the Herschel DIGIT programme
Waters, L. B. F. M.; Dominik, C.; Tielens, A. G. G. M. +4 more
Context. The spectra of protoplanetary disks contain mid- and far- infrared emission features produced by forsterite dust grains. The spectral features contain information about the forsterite temperature, chemical composition and grain size.
Aims: We aim to characterize how the 23 and 69 µm features can be used to constrain the physica…