Search Publications
Energy conversion regions as observed by Cluster in the plasma sheet
Dandouras, I.; André, M.; Hamrin, M. +5 more
In this article we present a review of recent studies of observations of localized energy conversion regions (ECRs) observed by Cluster in the plasma sheet at altitudes of 15-20RE. By examining variations in the power density, E · J, where E is the electric field and J is the current density, we show that the plasma sheet exhibits a hig…
A stringent upper limit to SO2 in the Martian atmosphere
Forget, F.; Encrenaz, T.; Atreya, S. K. +6 more
Surfur-bearing molecules have been found at the surface of Mars by the Viking lander, the Spirit and Opportunity rovers, and the OMEGA infrared spectrometer aboard Mars Express. However, no gaseous sulfur-bearing species have ever been detected in the Martian atmosphere. We search for SO2 signatures in the thermal spectrum of Mars at 7.…
Disentangling the Environment of the FU Orionis Candidate HBC 722 with Herschel
Henning, Thomas; Skinner, Stephen L.; Güdel, Manuel +16 more
We analyze the submillimeter emission surrounding the new FU Orionis-type object, HBC 722. We present the first epoch of observations of the active environs of HBC 722, with imaging and spectroscopy from PACS, SPIRE, and HIFI on board the Herschel Space Observatory, as well as CO J = 2-1 and 350 µm imaging (SHARC-II) with the Caltech Submill…
A Droplet Model of Quiescent Prominence Downflows
Berger, T.; Haerendel, G.
Observations of quiescent prominences with the Solar Optical Telescope on the Hinode satellite have revealed the ubiquitous existence of downflows forming coherent thin and highly structured vertically oriented threads with velocities between 10 and 20 km s-1. Their widths range between 300 and 500 km. They are often initiated at the to…
X-ray calibration of Sunyaev-Zel'dovich scaling relations with the ACCEPT catalogue of galaxy clusters observed by Chandra
Comis, B.; de Petris, M.; Lamagna, L. +2 more
We explore the scaling relation between the flux of the Sunyaev-Zel'dovich (SZ) effect and the total mass of galaxy clusters using already reduced Chandra X-ray data present in the ACCEPT (Archive of Chandra Cluster Entropy Profile Tables) catalogue. The analysis is conducted over a sample of 226 objects, examining the relatively small scale corre…
Super-Chandrasekhar SNe Ia Strongly Prefer Metal-poor Environments
Stanek, K. Z.; Prieto, J. L.; Stoll, R. +1 more
We discuss the emerging trend that super-Chandrasekhar Type Ia Supernovae (SCSNe) with progenitor mass estimates significantly exceeding ~1.4 M sun tend to explode in metal-poor environments. While Taubenberger et al. noted that some of the SCSNe host galaxies are relatively metal-poor, we focus quantitatively on their locations in the …
Temperature variability in X-ray bright points observed with Hinode/XRT
Kariyappa, R.; Damé, L.; Golub, L. +4 more
Aims: We investigate the variability in temperature as a function of time among a sample of coronal X-ray bright points (XBPs).
Methods: We analysed a 7-h (17:00-24:00 UT) long time sequence of soft X-ray images observed almost simultaneously in two filters (Ti_poly and Al_mesh) on April 14, 2007 with X-ray telescope (XRT) onboard the Hi…
Molecular gas in NUclei of GAlaxies (NUGA). XV. Molecular gas kinematics in the inner 3 kpc of NGC 6951
Schinnerer, E.; Baker, A. J.; Combes, F. +6 more
Within the NUclei of GAlaxies (NUGA) project we have obtained IRAM PdBI and 30 m 12CO(1-0) and 12CO(2-1) observations of the spiral galaxy NGC 6951. Previous work shows that there is indirect evidence of gas inflow from 3 kpc down to small radii: a large-scale stellar bar, a prominent starburst ring (r ≈ 580 pc) and a LINER/S…
Intensity contrast from MHD simulations and HINODE observations
Solanki, S. K.; Lagg, A.; Schüssler, M. +3 more
Context. Changes in the solar surface area, which is covered by small-scale magnetic elements, are thought to cause long-term changes in the solar spectral irradiance, which are important for determining the impact on Earth's climate.
Aims: To study the effect of small-scale magnetic elements on the total and spectral irradiance, we derive th…
Mapping Differential Reddening in the Inner Galactic Globular Cluster System
Mateo, Mario; von Braun, Kaspar; Alonso-García, Javier +2 more
A serious limitation in the study of many globular clusters—especially those located near the Galactic center—has been the existence of large and differential extinction by foreground dust. In a series of papers, we intend to map the differential extinction and remove its effects, using a new dereddening technique, in a sample of clusters in the d…