Search Publications
Mid-infrared interferometry towards the massive young stellar object CRL 2136: inside the dust rim
Lumsden, S. L.; Hoare, M. G.; de Wit, W. J. +3 more
Context. Establishing the importance of circumstellar disks and their properties is crucial to fully understand massive star formation.
Aims: We aim to spatially resolve the various components that make-up the accretion environment of a massive young stellar object (⪉100 AU), and reproduce the emission from near-infrared to millimeter wavelen…
Kinetic simulations of magnetic reconnection in presence of a background O+ population
Andersson, L.; Lapenta, G.; Markidis, S. +3 more
Particle-in-Cell simulations of magnetic reconnection with an H+ current sheet and a mixed background plasma of H+ and O+ ions are completed using physical mass ratios. Four main results are shown. First, the O+ presence slightly decreases the reconnection rate and the magnetic reconnection evolution dep…
EISCAT-Cluster observations of quiet-time near-Earth magnetotail fast flows and their signatures in the ionosphere
Nilsson, H.; Kauristie, K.; Amm, O. +3 more
We report observations of a sequence of quiet-time Earthward bursty bulk flows (BBFs) measured by the Cluster spacecraft in the near-tail plasma sheet (XGSM ~ -12 to -14 RE) in the evening sector, and by simultaneous high-resolution measurements in the northern conjugate ionosphere by the EISCAT radars, a MIRACLE all-sky camera and magn…
The Widespread Occurrence of Water Vapor in the Circumstellar Envelopes of Carbon-rich Asymptotic Giant Branch Stars: First Results from a Survey with Herschel/HIFI
Waters, L. B. F. M.; Olofsson, H.; Marston, A. P. +16 more
We report the preliminary results of a survey for water vapor in a sample of eight C stars with large mid-IR continuum fluxes: V384 Per, CIT 6, V Hya, Y CVn, IRAS 15194-5115, V Cyg, S Cep, and IRC+40540. This survey, performed using the HIFI instrument on board the Herschel Space Observatory, entailed observations of the lowest transitions of both…
A disc inside the bipolar planetary nebula M2-9
Smith, N.; Balick, B.; Lykou, F. +4 more
Aims: Bipolarity in proto-planetary and planetary nebulae is associated with events occurring in or around their cores. Past infrared observations have revealed the presence of dusty structures around the cores, many in the form of discs. Characterising those dusty discs provides invaluable constraints on the physical processes that govern th…
A deep Chandra observation of the poor cluster AWM 4 - II. The role of the radio jets in enriching the intracluster medium
Raychaudhury, Somak; Giacintucci, Simona; Vrtilek, Jan M. +2 more
We use a Chandra observation of the poor cluster AWM 4 to map the temperature and abundance of the intracluster medium, so as to examine the influence of the central radio galaxy on its environment. While the cluster core is generally enriched to near-solar abundances, we find evidence of supersolar abundances correlated with the radio jets, exten…
Modeling the Oxygen K Absorption in the Interstellar Medium: An XMM-Newton View of Sco X-1
Quinet, P.; García, J.; Kallman, T. R. +5 more
We investigate the X-ray absorption structure of oxygen in the interstellar medium by analyzing XMM - Newton observations of the low-mass X-ray binary Sco X-1. Simple models based on the O I atomic photoabsorption cross section from different sources are used to fit the data and evaluate the impact of the atomic data on the interpretation of the o…
Auroral electron distributions within and close to the Saturn kilometric radiation source region
Schippers, P.; André, N.; Gurnett, D. A. +11 more
On 17 October 2008, Cassini observed for the first time the electron populations associated with the crossing of a Saturn kilometric radiation source region and its surroundings. These observations allow for the first time the constraint and quantification of the high-latitude acceleration processes, the current systems, and the origin of the low-…
Multiwavelength modelling of the β Leo debris disc: one, two or three planetesimal populations?
Duchêne, G.; Wyatt, M. C.; Greaves, J. +7 more
In this paper we present a model of the β Leo debris disc, with an emphasis on modelling the resolved Photodetector Array Camera and Spectrometer (PACS) images obtained as a part of the Herschel key programme DEBRIS. We also present new Spectral and Photometric Imaging REceiver (SPIRE) images of the disc at 250 µm, as well as new constraints…
Observation of Diffuse Cosmic and Atmospheric Gamma Rays at Balloon Altitudes with an Electron-tracking Compton Camera
Okada, Yoko; Hattori, Kaori; Nagayoshi, Tsutomu +13 more
We observed diffuse cosmic and atmospheric gamma rays at balloon altitudes with the Sub-MeV gamma-ray Imaging Loaded-on-balloon Experiment I (SMILE-I) as the first step toward a future all-sky survey with a high sensitivity. SMILE-I employed an electron-tracking Compton camera comprised of a gaseous electron tracker as a Compton-scattering target …