Search Publications
Flare energetics: analysis of a large flare on YZ Canis Minoris observed simultaneously in the ultraviolet, optical and radio.
Doyle, J. G.; Pagano, I.; Linsky, J. L. +7 more
The results of coordinated observations of the dMe star YZ CMi at optical, UV and radio wavelengths during 3-7 February 1983 are presented. YZ CMi showed repeated optical flaring with the largest flare having a magnitude of 3.8 in the U-band. This flare coincided with an IUE exposure which permits a comparison of the emission measure curves of YZ …
A comparison of interplanetary coronal mass ejections at ULYSSES with YOHKOH soft X-ray coronal events.
Forsyth, R. J.; Burkepile, J. T.; Phillips, J. L. +5 more
Coronal Mass Ejections (CMEs) observed at several AU by the Ulysses spacecraft are mapped radially back to the Sun and compared with Yohkoh Soft X-ray Telescope (SXT) images of the corona in an effort to identify correlated events. Correlations between the observations were difficult to make during the ecliptic phase of the Ulysses mission when th…
ISO observations of Wolf-Rayet galaxy Haro 3.
Hanlon, L.; McBreen, B.; Clavel, J. +9 more
Observations of the blue compact dwarf galaxy Haro 3 have been obtained with the ISOCAM and ISOPHOT instruments on the Infrared Space Observatory (ISO). The PHT-S spectrum (6-12µm) is dominated by four emission bands that are frequently attributed to polycyclic aromatic hydrocarbons (PAHs) and strong SIV emission. Two CAM filters, LW6 (7-8.5…
ULYSSES at high heliographic latitudes: an introduction.
Smith, E. J.; Cooper, J. F.; Marsden, R. G. +1 more
The unique in situ observations acquired by the scientific instrumentation on board the Ulysses spacecraft have provided, for the first time, a comprehensive, 3-dimensional view of the heliosphere from the solar equator to the poles near solar minimum. Since beginning its journey out of the ecliptic plane in February, 1992, Ulysses has acquired a …
ISOCAM observations of NGC 6946: Mid-IR structure.
Helou, G.; Lord, S. D.; Malhotra, S. +12 more
The nearby spiral galaxy NGC 6946 was observed with ISO-CAM in the mid-infrared, achieving 7" resolution and sub-MJy/sr sensitivity. Images taken with CAM filters LW2 (7µm) and LW3 (15µm) are analysed to determine the morphology of this galaxy and understand better the emission mechanisms. The mid-infrared emission follows an exponenti…
The infrared and radio continuum of early-type stars.
Blomme, R.; Runacres, M. C.
The infrared and radio continuum fluxes of 18 well-observed early-type stars are studied by comparing observations with theoretical models. The observations are taken from the literature. All available observations are included. The theoretical NLTE models for photosphere and stellar wind include free-free and free-bound emission as well as electr…
ISOPHOT Maps of NGC 6946 in the range λ 60-200µm.
Helou, G.; Lemke, D.; Gabriel, C. +7 more
We present maps of NGC 6946 at λ 61 and 205µm as well as scans through the galaxy at these and at 8 intermediate wavelengths. The bulk of the FIR luminosity arises from a diffuse disk component which extends beyond the 25mag/arcsec^2^ B isophote to at least the radius corresponding to the sensitivity limit. A FIR emission counterpart to the …
Accretion torques in the transient X-ray pulsar EXO2030+375.
Parmar, A. N.; Verbunt, F.; Wilson, R. B. +4 more
In 1985 May - October, EXOSAT observed two outbursts from the previously unknown accreting X-ray pulsar EXO2030+375. Using the orbital solution derived by the BATSE experiment on CGRO, the behavior of the pulse period variations can now be studied with much less ambiguity than was possible based on the EXOSAT observations alone. There is little ev…
PU Vulpeculae: an eclipsing symbiotic nova.
Vogel, M.; Nussbaumer, H.
A series of IUE observation from 1992 to 1995 has definitely established PU Vul as an eclipsing binary. The outburst of this symbiotic nova began in 1977. An extended fading in 1980 gave rise to various interpretations, the eclipse scenario being one of them, dust formation being another. From AFOEV and AAVSO observations we find a period of 4900+…
On the width of the theoretical lower main sequence. Consequences for the determination of the {DELTA}Y/{DELTA}Z ratio in the solar neighbourhood.
Baglin, A.; Lebreton, Y.; Fernandes, J.
We discuss the relation between the main sequence thickness and chemical composition variations. With the help of theoretical zero-age main sequence models between 0.7 and 1.0Msun_, computed with an advanced physical description of the stellar interiors, in a range of metallicities typical from Population I stars (0.008<=Z<=0.034)…