Results 61 to 70 of about 111 (106)

The EUV spectrum of sunspot plumes observed by SUMER on SOHO

Journal of Astrophysics and Astronomy, 2000
AbstractWe present results from sunspot observations obtained by SUMER on SOHO. In sunspot plumes the EUV spectrum differs from the quiet Sun; continua are observed with different slopes and intensities; emission lines from molecular hydrogen and many unidentified species indicate unique plasma conditions above sunspots.
Curdt, W., Dwivedi, B., Feldman, U.
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EUV Line Diagnostics for CDS and Sumer on SOHO

International Astronomical Union Colloquium, 1994
AbstractThe EUV line diagnostics for the CDS and the SUMER instruments, to be flown onboard the SOHO mission, are discussed. Serts observations of EUV line intensities in an active region, reported by Thomas and Neupert (1993), have been used to determine the electron density and temperature from a theoretical curve of Mg VIII density-sensitive line ...
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Observation of Transition Region Fine Structures with Soho/Sumer

Space Science Reviews, 1999
We present a preliminary analysis of two quiet Sun transition region areas observed with the SOHO/SUMER spectrometer, using lines from oxygen, nitrogen and silicon. The average quiet Sun physical parameters are studied as a function of line intensity. Systematic variations of line position and width with increasing intensity are found.
E. Landi, H. E. Mason, M. Landini
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Study of the quiet corona with the SOHO/SUMER spectrometer

Advances in Space Research, 1994
The Solar and Heliospheric Observatory (SOHO)/Solar Ultraviolet Measurement of Emitted Radiations (SUMER) spectrometer is developed to study the low corona and chromosphere-corona transition zone. The main scientific objectives are oriented towards the search of mechanisms producing the coronal heating and driving the first impulse of the solar wind ...
Lemaire, P., Wilhelm, K.
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Comparison of quiet-Sun radiances measured by CDS and SUMER on SOHO

Space Science Reviews, 2001
Since the beginning of the SOHO (Solar and Heliospheric Observatory) mission an intercalibration programme was carried out which included simultaneous observations of the EUV instruments CDS (Coronal Diagnostic Spectrometer) and SUMER (Solar Ultraviolet Measurements of Emitted Radiation) of common targets on the quiet Sun.
Pauluhn, A., Solanki, S., Schühle, U., Wilhelm, K., Lang, J., Thompson, W., Rüedi, I., Hollandt, J., Huber, M.   +8 more
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Multiple-Thread Model of a Prominence Observed by Sumer and eit on Soho

Solar Physics, 1999
A quiescent polar crown prominence was observed at Meudon in Hα and Ca ii lines, and by EIT and SUMER on board SOHO in UV lines from 9 to 10 March 1996. SUMER observed the prominence continuously in a scanning mode between 21:40 UT on 9 March, and 18:13 UT on 10 March, in the nitrogen line N v (λ1238) with a 1 arc sec2 resolution.
Wiik, J., Dammasch, I., Schmieder, B., Wilhelm, K.   +3 more
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Chromospheric Dynamics as Can Be Inferred from Sumer/SOHO Observations

2001
Experience with the SUMER/SOHO observations of the chromospheric dynamics and the reduction of the acquired data is summarized on base of the SOHO Joint Operation Program 78 which is focused on the variability of the chromosphere and the transition region to the corona.
Rybak, J., Kucera, A., Curdt, W., Schühle, U., Wöhl, H.   +4 more
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Spectral Diagnostics of the Magnetic Field Orientation in a Prominence Observed with SOHO/SUMER

Solar Physics, 2007
During several campaigns focused on prominences we have obtained coordinated spectral observations from the ground and from space. The SOHO/SUMER spectrometer allows us to observe, among others, the whole Lyman series of hydrogen, while the Hα line was observed by the MSDP spectrograph at the VTT.
Schmieder, Brigitte, Gunár, Stanislav, Heinzel, Petr, Anzer, U.   +3 more
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The low-latitude inner corona of the sun observed by SUMER on SOHO

AIP Conference Proceedings, 1999
High-resolution spectra obtained by the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrograph in both spectral and spatial regimes provided the opportunity to study streamer plasmas in detail at low and medium solar latitudes of the inner corona.
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Eruptive prominence and associated CME observed with SUMER, CDS and LASCO (SOHO)

Solar Physics, 1997
Observations of an eruptive prominence were obtained on 1 May 1996, with the SUMER and CDS instruments aboard SOHO during the preparatory phase of the Joint Observing Programme JOP12. A coronal mass ejection observed with LASCO is associated temporally and spatially with this prominence.
J. E. Wiik, B. Schmieder, T. Kucera, A. Poland, P. Brekke, G. Simnett   +5 more
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