Search Publications
Very long period activity at the base of solar wind streams
Doyle, J. G.; Xia, L. D.; Banerjee, D. +2 more
Using time series data of spectral lines originating from a wide range of temperatures in the solar transition region, above a polar coronal hole, from SUMER (Solar Ultraviolet Measurements of Emitted Radiation) on SoHO (Solar and Heliospheric Observatory), we report on the detection of very long (≈170 min) periodic intensity fluctuations, above t…
The Chemical Composition and Equation of State of the Sun Inferred from Seismic Models through an Inversion Procedure
Lin, Chia-Hsien; Däppen, Werner
The remarkable quality of present helioseismic data provides the possibility to investigate the microscopic physics of the solar interior. An inversion procedure to reveal the equation of state and chemical composition in the Sun has been developed. The method is based on using the discrepancy in the adiabatic gradient γ1≡(∂lnP/∂lnρ)
Millisecond radio spikes in the decimetre band and their related active solar phenomena
Siarkowski, M.; Falewicz, R.; Rudawy, P. +2 more
We present here a brief description of thirteen events of the narrowband solar millisecond radio spike emissions observed between February 2000 and December 2001. The total observing time was 1990.4 h, collected during the 357 observing days. The data were collected with the 15-m radio telescope and fast radiospectrograph of Toruń Observatory, Pol…
SMART-1: Development and lessons learnt
Rathsman, Peter; Kugelberg, Joakim; Bodin, Per +3 more
SMART-1 is the first of the small missions for advanced research and technology as part of ESA's science programme “Cosmic vision”. It was successfully launched on September 27, 2003 and is presently traveling towards its destination, the Moon. The main objective of the mission, to demonstrate solar electric primary propulsion for future Cornersto…
HST and spectroscopic observations of the L1551 IRS5 jets (HH154)
Liseau, R.; White, G. J.; Favata, F. +4 more
We have carried out a thorough optical study of the closest star formation jet. The inner arcminute surrounding the class 0/I binary protostar L1551 IRS5 and its associated jet (HH154) have been observed using the Hubble Space Telescope with the WFPC2 camera, the ESO New Technology Telescope with the EMMI spectrograph and the Nordic Optical Telesc…
Detection of Silicon Nitride Particles in Extreme Carbon Stars
Sturm, E.; Mutschke, H.; Henning, Th. +4 more
On the basis of spectra taken by the Infrared Space Observatory and laboratory measurements, we present the first spectroscopic evidence for the presence of silicon nitride (Si3N4) grains in the circumstellar shells of a number of extreme carbon stars. Laboratory measurements of α, β, and amorphous Si3N4…
VLT UVES Observations of the Balmer Line Variations of η Carinae during the 2003 Spectroscopic Event
Weis, K.; Stahl, O.; Bomans, D. J. +3 more
We present high spectral resolution echelle observations of the Balmer line variations during the 2003.5 ``spectroscopic event'' of η Carinae. Spectra have been recorded of both η Car and the Homunculus at the ``FOS4'' position in its southeast lobe. This spot shows a reflected stellar spectrum that is less contaminated by nebular emission lines t…
Correlation between coronal hole and quiet Sun intensities: Evidence for continuous reconnection
Del Zanna, G.; Raju, K. P.; Bromage, B. J. I. +1 more
Intensities of 12 strong EUV emission lines in a coronal hole and the neighbouring quiet Sun region have been obtained from SOHO/CDS observations made in August and September 1996. The field of view is 1 arcmin wide by 4 arcmin, with a series of observations made at different spatial locations on the boundary of the north polar hole and its large …
First Ultraviolet Spectrum of a Brown Dwarf: Evidence for H2 Fluorescence and Accretion
Gizis, John E.; Shipman, Harry L.; Harvin, James A.
We analyze an HST STIS ultraviolet spectrum of the young brown dwarf 2MASSW J1207334-393254, a member of the 10 million year old TW Hya association that has a planetary-mass companion. We detect and identify numerous emission lines. C IV and other ions are seen that arise in hot gas. We identify a series of lines with Lyman-pumped H2 mo…
The Near-Earth Solar Wind
Eastwood, J. P.; Lucek, E. A.; Décréau, P. +3 more