Search Publications
Missions
Journals
Publication Years
Generation of downshifted oscillations in the electron foreshock: A loss-cone instability
Schwartz, S. J.; Fazakerley, A.; Décréau, P. +4 more
Measurements performed aboard Cluster spacecraft near Earth's bow shock on 24 January 2001 provide convincing evidence of a loss-cone feature within the electron foreshock region. This feature is formed by suprathermal electrons with energies 15-45 eV and pitch angles 130°-150° and is always accompanied by electrostatic waves with frequencies well…
The dynamics of velocity fluctuations in the solar wind - I. Coronal mass ejections
Raga, A. C.; Lara, A.; de Gouveia Dal Pino, E. M. +3 more
In this paper we present a simple, analytic model for the dynamical evolution of supersonic velocity fluctuations at the base of the ambient solar wind. These fluctuations result in the formation of dense working surfaces that travel down the wind. It is shown how the initial parameters of the fluctuations (velocity, density and duration) are rela…
Flare-associated Coronal Disturbances Observed with the Norikura Green-Line Imaging System. I. A Coronal Mass Ejection Onset
Ichimoto, K.; Sakurai, T.; Hori, K. +2 more
We present the first detection of an onset of a coronal mass ejection (CME) in the coronal green-line emission (Fe XIV λ5303, 2 MK) by the two-dimensional Doppler coronagraph NOGIS (Norikura Green-Line Imaging System) at the Norikura Solar Observatory, National Astronomical Observatory of Japan. On 2003 June 1-2, NOGIS continuously observed the bi…
A Multiwavelength Study of IC 63 and IC 59
Martin, P. G.; Noriega-Crespo, A.; Karr, J. L.
IC 63 and IC 59 are two nearby arc-shaped nebulae with relatively simple geometries and minimal obscuring material. The two regions, in spite of a similar projected distance from their ionizing star, have very different observational properties, both in continuum emission and in the presence and strength of line emission from molecular species. Th…
Discovery of Ne VII in the Winds of Hot Evolved Stars
Hillier, D. J.; Bianchi, L.; Herald, J. E.
We show that a strong P Cygni feature seen in the far-UV spectra of some very hot (Teff>~85 kK) central stars of planetary nebulae (CSPN), which has been previously identified as C III λ977, actually originates from Ne VII λ973. Using stellar atmosphere models, we reproduce this feature seen in the spectra of two [WR] PG 1159-type CS…
Orbits of new Hipparcos binaries. I
Weigelt, G.; Hofmann, K. -H.; Schertl, D. +4 more
We present first orbits for 6 new Hipparcos binaries. The orbits were determined from speckle interferometric measurements collected mainly at the6m BTAtelescope of the Special Astrophysical Observatory in Zelenchuk. Three of the systems, HIP 11352, HIP 14075 and HIP 14230, have late G- or early K-type components, while HIP 14669 = GJ 125, HIP 106…
Optical Identification of Infrared Space Observatory Far-Infrared Sources in the Lockman Hole Using a Deep Very Large Array 1.4 GHz Continuum Survey
Veilleux, S.; Sanders, D. B.; Kawara, K. +10 more
By exploiting the far-infrared (FIR) and radio correlation, we have performed a likelihood-ratio analysis to identify optical counterparts to the FIR sources that have been found in an area of ~0.9 deg2 during the Infrared Space Observatory (ISO) deep FIR survey in the Lockman Hole. New ground-based observations have been conducted to b…
The dark halo of the main lens galaxy in QSO 0957 + 561
Gil-Merino, R.; Goicoechea, L. J.; Ullán, A.
We present an analysis of infrared/optical/ultraviolet spectra of the two images of the first gravitationally lensed quasar Q0957 + 561A,B. The Hubble Space Telescope observations of Q0957 + 561A and Q0957 + 561B are separated in time by the known time delay in this system, so we can directly deduce the flux ratios. These flux ratios of images lea…
Extragalactic Source Counts in the Spitzer 24 Micron Band: What Do We Expect from ISOCAM 15 Micron Data and Models?
Pozzi, F.; Rodighiero, G.; Gruppioni, C. +2 more
The comparison between the new Spitzer data at 24 µm and the previous ISOCAM data at 15 µm is a key tool to understand galaxy properties and evolution in the infrared and to interpret the observed number counts, since the combination of Spitzer with the Infrared Space Observatory cosmological surveys provides for the first time the dir…
High spectral and temporal resolution observations of Saturn kilometric radiation
Gurnett, D. A.; Hospodarsky, G. B.; Kurth, W. S. +7 more
This paper presents the first high-resolution dynamic spectra of Saturn kilometric radiation acquired upon Cassini's approach and first orbits of Saturn. The emissions display upward and downward drifting features with bandwidths down to ~200 Hz and drift rates of a few kHz per second. At other times, the emissions are much more diffuse or continu…