Search Publications
Gravitationally lensed high redshift galaxies in the field of 1E0657-56
Saglia, R. P.; Pauldrach, A. W. A.; Bender, R. +7 more
We present images and long-slit spectra obtained with FORS1 at UT1 of the VLT centered on the gravitational arc of the galaxy cluster 1E0657-56 (z = 0.296). The cluster is one of the hottest, most massive clusters known so far and acts as a powerful gravitational telescope, amplifying the flux of background sources by up to a factor of 20. We pres…
Plumes and oscillations in the sunspot transition region
Wilhelm, K.; Kjeldseth-Moe, O.; Brynildsen, N. +1 more
The suggestion that sunspot transition region oscillations are a typical feature of the sunspot plumes is examined. The present observations show 3 min oscillations in the umbra that end at the umbral rim. We find that sunspot plumes located above the umbra show these oscillations, in contrast to plumes above the penumbra. These two findings sugge…
XMM-Newton survey of the low-metallicity open cluster NGC 2516
Gondoin, P.; Read, A. M.; Grosso, N. +8 more
We present the first results of an XMM-Newton EPIC survey of NGC 2516, a southern low-metallicity open cluster with an age close to the Pleiades. The attained limiting sensitivity is of ~ 2.4 10-15 erg s-1 cm-2 in the 0.1-4.0 keV bandpass. This has been achieved by summing the data of the MOS and PN cameras of two …
System parameters of the long-period polar V1309 Ori
Schwope, A. D.; Schwarz, R.; Staude, A.
Based on high-resolution optical spectroscopy in the blue and the near infra-red spectral range, we derived velocity images (Doppler tomograms) of the mass-donating secondary star and the accretion stream of the long-period eclipsing polar V1309 Ori (RX J0515.41+0104.6). Combined with HST-spectroscopy of high time resolution and optical photometry…
Dynamical mass determination for the very low mass stars LHS 1070 B and C
Mazeh, T.; Zucker, S.; Leinert, Ch. +4 more
We followed the relative orbit of the close pair of very late-type stars in the nearby triple system LHS 1070 during the past seven years. These observations are used to derive the astrometric elements of the orbit. Using the period of 16.1 +/- 1.4 years and assuming the distance of 7.39 pc given by van Altena (\cite{vanaltena95}) to be exactly co…
Millimeter-radio, SOHO/EIT 171 Å features and the polar faculae in the polar zones of the Sun
Urpo, S.; Valtaoja, E.; Riehokainen, A. +3 more
In this work we study different manifestations of activity in the polar zones of the Sun in order to gain understanding on the phenomenon of enhanced radio temperature regions (ETR) at high solar latitudes. We have obtained simultaneous radio and optical data during 9 days in 1997. The radio data from the Metsähovi radio telescope, Finland, consis…
The physical conditions in the PDR of W49N
Ceccarelli, C.; Caux, E.; Vastel, C. +2 more
We present ISO-LWS and ground-based SEST observations which probe the Photo Dissociation Region (PDR) of W49N. The ISO-LWS observations consist of low resolution ( ~ 200) grating spectra between 43 mu m and 197 mu m, and high resolution ( ~ 104) Fabry-Pérot spectra of the [CII] 158 mu m and [OI] 63 and 145 mu m lines. The SEST observati…
The velocity field of UGC 6697 revisited
Tarenghi, M.; Boselli, A.; Gavazzi, G. +4 more
The edge-on galaxy UGC 6697 has a peculiar morphological appearance: a high surface brightness SE component and what appears to be a tidal tail with blue color and low surface brightness extending toward the NW, as dramatically evidenced in subarcsecond broad band images taken with the VLT and in a deep Halpha frame. Long-slit spectros…
The eclipsing bursting X-ray binary EXO 0748-676 revisited by XMM-Newton
Haberl, F.; Bonnet-Bidaud, J. M.; Ferrando, P. +2 more
The bright eclipsing and bursting low-mass X-ray binary EXO 0748-676 has been observed at several occasions by XMM-Newton during the initial calibration and performance verification (CAL/PV) phase. We present here the results obtained from observations with the EPIC cameras. Apart from several type-I X-ray bursts, the source shows a high degree of…
Coordinated observations of the quiet Sun transition region using SUMER spectra, TRACE images and MDI magnetograms
Innes, D. E.
The relationship between the transition region ultraviolet emission and the underlying magnetic field is explored through a detailed analysis of SUMER SI IV line profiles, TRACE C IV, continuum and 171 Å intensities, and MDI high resolution magnetic field measurements. The observations track a narrow area of quiet Sun near disk center over a perio…