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An upper limit of the number and energy of electrons accelerated at an extended coronal shock wave
Klein, K. -L.; Lecacheux, A.; McTiernan, J. M. +3 more
Type II radio emission is the most direct signature of extended shock waves in the solar corona, and a prime example of electron acceleration at a shock. Yet, the energetics of these electrons is poorly known. On 1996 August 19 and 1997 October 07 type II bursts were observed in association with flares behind the solar limb. While Earth-orbiting X…
Diffuse continuum emission from the inner Galaxy: First results from INTEGRAL/SPI
Strong, A. W.; Bouchet, L.; Schönfelder, V. +3 more
We present a preliminary analysis of the diffuse hard X- and soft gamma -ray continuum emission from the inner Galactic ridge using INTEGRAL/SPI data from the first Galactic Plane Deep Exposure and Galactic Plane Scans. The spectrum is consistent with results from previous experiments. These early results demonstrate the potential of the INTEGRAL …
Inversion of the intensity-magnetic field relationship in solar active regions
Fludra, A.; Ireland, J.
We discuss the relationship between the EUV spectral line intensities and the photospheric magnetic flux in solar active regions. Since the histograms of the magnetic flux density in active region plages can be approximated by an exponential function, the equation describing how the observed total line intensity integrated over an active region ar…
[C II] emission and star formation in late-type galaxies. II. A model
Völk, H. J.; Pierini, D.; Leech, K. J.
We study the relationship between gas cooling via the [C II] (lambda = 158 µm) line emission and dust cooling via the far-IR continuum emission on the global scale of a galaxy in normal (i.e. non-AGN dominated and non-starburst) late-type systems. It is known that the luminosity ratio of total gas and dust cooling, LC II/ LFI…
On the origin of microwave type U-bursts
Kuznetsov, A. A.; Altyntsev, A. T.; Meshalkina, N. S. +1 more
An analysis is made of the observations of U-type cm-bursts recorded simultaneously with high spatial (Siberian solar radio telescope) and spectral resolution (National Astronomical Observatories/Beijing spectropolarimeters). It is shown that the source positions of increasing and decreasing branches of the U-burst coincide within a few arcsec. Th…
An outflow from the nebula around the LBV candidate S 119
Weis, K.; Bomans, D. J.; Duschl, W. J.
We present an analysis of the kinematic and morphological structure of the nebula around the LMC LBV candidate S 119. On HST images, we find a predominantly spherical nebula which, however, seems to be much better confined in its eastern hemisphere than in the western one. The filamentary western part of the nebula is indicative of matter flowing …
The radial velocity curve of HD 153919 (4U 1700-37) revisited
van Kerkwijk, M. H.; Hammerschlag-Hensberge, G.; Kaper, L.
We have re-analysed all available high-resolution ultraviolet IUE spectra of the high-mass X-ray binary HD 153919/4U 1700-37. The radial velocity semi-amplitude of 20.6 +/- 1.0 km s-1 and orbital eccentricity of 0.22 +/- 0.04 agree very well with the values obtained earlier from optical spectra. They disagree with earlier conclusions fo…
Modeling far-infrared line emission from the HII region S125
Emery, R. J.; Aannestad, P. A.
We present ISO-LWS spectral line observations of the [OI] 63 and 146 mu m lines, the [CII] 158 mu m line, and the [NII] 122 mu m line at 17 positions in the HII region S125. We model this emission by a two-dimensional geometrical blister model, utilizing the parameters derived from our previous modeling of the HII, HI and FIR dust emission in this…
Sunspot plume observations in the EUV. The gas pressure differential between the umbra and surrounding region
Doyle, J. G.; Madjarska, M. S.
The electron density over a bright sunspot plume region was evaluated using lines within the O V 760 Å multiplet. The plume showed an intensity enhancement factor of ~9 in the O V lines compared to regions outside the sunspot umbra. Internal agreement between the various ratios is excellent which would suggest that the O V lines do not suffer from…
The quest for hot gas in the halo of NGC 1511
Ehle, M.; Jansen, F.; Heckman, T. M. +3 more
XMM-Newton observations of the starburst galaxy NGC 1511 reveal the presence of a previously unknown extended hot gaseous phase of its ISM, which partly extends out of the disk plane. The emission distribution is asymmetric, being brightest in the eastern half of the galaxy, where also radio continuum observations suggest the highest level of star…