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Optical observations of the young supernova remnant SNR 0540-69.3 and its pulsar
Sollerman, J.; Lundqvist, P.; Shibanov, Yu. A. +1 more
We have used the ESO NTT/EMMI and VLT/FORS1 instruments to examine the LMC supernova remnant 0540-69.3 as well as its pulsar (PSR B0540-69) and pulsar-powered nebula in the optical range. Spectroscopic observations of the remnant covering the range of 3600-7350 Å centered on the pulsar produced results consistent with those of [Kirshner, R.P., Mor…
AFS dynamics in a short-lived active region
Romano, P.; Spadaro, D.; Contarino, L. +3 more
In the framework of the study on active region emergence, we report the results obtained from the analysis of the short-lived (7 days) active region NOAA 10407. The data used were acquired during an observational campaign carried out with the THEMIS telescope in IPM mode in July 2003, coordinated with other ground- and space-based instruments (INA…
Comparison of GONG and MDI: Sound-Speed Anomalies beneath Two Active Regions
Thompson, M. J.; Rajaguru, S. P.; Hughes, S. J.
Travel times of acoustic waves are calculated from Dopplergrams of solar oscillations obtained using the Global Oscillation Network Group (GONG) ground-based network and the Michelson Doppler Imager (MDI) instrument on board the SOHO satellite. These travel times are inverted using a standard ray approximation to ascertain the sound-speed anomalie…
Detection of X-ray emission from β Pictoris with XMM-Newton: a cool corona, a boundary layer or what?
Schmitt, J. H. M. M.; Ness, J. -U.; Robrade, J. +1 more
β Pictoris (
Polar heating in Saturn's thermosphere
Müller-Wodarg, I. C. F.; Miller, S.; Smith, C. G. A. +1 more
A 3-D numerical global circulation model of the Kronian thermosphere has been used to investigate the influence of polar heating. The distributions of temperature and winds resulting from a general heat source in the polar regions are described. We show that both the total energy input and its vertical distribution are important to the resulting t…
Modeling the Energy Budget of Solar Wind Minor Ions: Implications for Temperatures and Abundances
Lie-Svendsen, Øystein; Esser, Ruth
The outflow of oxygen and silicon ions in the solar wind has been studied using a model that extends from the chromosphere into interplanetary space, with emphasis on understanding the energy budget of the minor ions. The model solves coupled gyrotropic transport equations, which account for temperature anisotropies and heat conduction, for all ch…
Simultaneous X-ray and optical spectroscopy of the Seyfert galaxy Mrk 993
Barcons, X.; Carrera, F. J.; Mateos, S. +2 more
We present the results of simultaneous XMM-Newton X-ray and 3.5 m/CAHA optical spectroscopic observations of the Seyfert galaxy Mrk 993. This galaxy exhibited in the past significant variations of its broad emission lines which classified it as Sy1, Sy1.5 and Sy1.9 in different epochs. In order to test the X-ray/optical consistency of the unified …
A Search for Substellar Companions around 15 Weak-Lined T Tauri Stars with the Planetary Camera 2 of the Hubble Space Telescope
Torres, Guillermo; Latham, David W.; Oppenheimer, Benjamin D. +2 more
To search for thermal emission from substellar companions, we have obtained Z-band images of 15 weak-lined T Tauri stars in the Taurus-Auriga and Ophiuchus star-forming regions using the Planetary Camera 2 on the Hubble Space Telescope. We found 18 faint nearby objects at separations larger than 4" but none at smaller separations. For 11 of these …
New insights into the dust properties of the Taurus molecular cloud TMC-2 and its surroundings
del Burgo, C.; Laureijs, R. J.
We present ISOPHOT observations at 120 and 200 µm of a 31 × 57 arcmin2 region, with optical extinction AV ranging between ~ 0.5 and 11 mag, that encloses the Taurus molecular cloud TMC-2. The far-infrared emission is separated into a warm and a cold component using the ISOPHOT data and IRAS measurements at 60 and 100 &m…
Mass Flows in a Disappearing Sunspot Plume
Brosius, Jeffrey W.
We observed a large sunspot in NOAA Active Region 9535 on 2001 July 12, 15, 17, and 19 with three instruments (CDS, EIT, and MDI) on board SOHO. EUV emission lines of O IV (formed at logarithmic temperature of 5.2), O V (5.4), Ne IV (5.2), Ne V (5.5), Ne VI (5.6), Ne VII (5.7), and Ca X (5.9) revealed a large bright plume within the sunspot penumb…