Search Publications
THEMIS/MSDP magnetic field measurements
Schmieder, B.; Berlicki, A.; Mein, P.
We present an analysis of longitudinal magnetic field measurements using the spectral data obtained with the French - Italian polarisation free telescope THEMIS working in Multichannel Subtractive Double Pass (MSDP) mode. We also used SOHO/MDI data to extend our analysis. THEMIS observations in the MSDP mode allows us to perform imaging spectropol…
Plasma Diagnostics of the Large-Scale Corona with SUMER. I. Measurements at the West Limb
Landi, E.; Doschek, G. A.; Feldman, U.
In the present work we analyze the physical properties of the quiet-Sun plasma measured in a 0.5×1.8 Rsolar region above the west solar limb (Rsolar=solar radius). We make use of large scans obtained with the SUMER spectrometer on board SOHO to construct two-dimensional spatial maps of line intensities, electron temperature, …
Constraints on the nature of dust particles by infrared observations
Ábrahám, P.; Birkmann, S. M.; Laureijs, R. J. +2 more
The far-infrared (FIR) emissivity of dust is an important parameter characterizing the physical properties of the grains. With the availability of stellar data bases and FIR data from Infrared Space Observatory (ISO), it is possible to compare the optical and infrared properties of dust, and derive the FIR emissivity with respect to the optical ex…
037-B327 in M31: Luminous Globular Cluster or Core of a Former Dwarf Spheroidal Companion to M31?
Zhou, Xu; van den Bergh, Sidney; Ma, Jun +6 more
The cluster 037-B327 is of interest because it is both the most luminous and the most highly reddened cluster known in M31. Deep observations with the Advanced Camera for Surveys on the Hubble Space Telescope provide photometric data in the F606W band and also show that this cluster is crossed by a dust lane. We have determined the structural para…
Hipparcos astrometric orbits for two brown dwarf companions: HD 38529 and HD 168443
Quirrenbach, A.; Reffert, S.
Context: .HD 38529 and HD 168443 have previously been identified as systems with two substellar companion candidates using precise radial velocity measurements.Aims.We want to further constrain their orbits and the nature of the outer companions.Methods.We fit astrometric orbits of the outer substellar companions in the two systems to the Hipparco…
Optical/near-infrared observations of the black hole candidate XTE J1720-318 : from high-soft to low-hard state
Chaty, S.; Bessolaz, N.
Aims.To gain a better understanding of high-energy Galactic sources, we observed the Galactic X-ray binary and black hole candidate XTE J1720-318 in the optical and near-infrared, just after the onset of its X-ray outburst in January, 2003. These observations were obtained with the ESO/NTT as the Target of Opportunity, in February and April 2003.<…
Multiplet structure of acceleration processes in the distant magnetotail
Zelenyi, L. M.; Sauvaud, J. -A.; Grigorenko, E. E. +1 more
We have studied ion distributions measured in the Plasma Sheet Boundary Layer (PSBL) of the Earth's magnetotail by the Cluster spacecraft at X ~ -15Re. Field-aligned ion beams (beamlets) accelerated in the magnetotail to energies of ~30keV are typically observed within the interface region between the Plasma Sheet (PS) and the magnetotail lobes. P…
The Frequency of Binary Kuiper Belt Objects
Elliot, J. L.; Kern, S. D.
We estimate the frequency of widely spaced (separations greater than 0.5") Kuiper Belt binaries (KBBs) from surveys for new Kuiper Belt objects (KBOs) with the Deep Ecliptic Survey and through recovery observations for newly discovered KBOs at the Magellan telescopes. We find the frequency of KBBs versus discovery separation to be related by an in…
The intensity contrast of solar photospheric faculae and network elements. II. Evolution over the rising phase of solar cycle 23
Sanahuja, B.; Ortiz, A.; Domingo, V.
We studied the radiative properties of small magnetic elements (active region faculae and the network) during the rising phase of solar cycle 23 from 1996 to 2001, determining their contrasts as a function of heliocentric angle, magnetogram signal, and the solar cycle phase. We combined near-simultaneous full disk images of the line-of-sight magne…
Cassini observations of the Interplanetary Medium Upstream of Saturn and their relation to the Hubble Space Telescope aurora data
Dougherty, M. K.; Jackman, C. M.; Clarke, J. T. +3 more
We present Cassini magnetometer and plasma data for the January 2004 ‘solar wind campaign’ in which the particles and fields instruments monitored the solar wind and interplanetary magnetic field, while the Hubble Space Telescope (HST) simultaneously observed the UV aurora in Saturn’s southern ionosphere. Clear structuring is evident in the data w…