Astronomy and Astrophysics – Astronomy
Scientific paper
May 1993
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1993aj....105.1973j&link_type=abstract
Astronomical Journal (ISSN 0004-6256), vol. 105, no. 5, p. 1973-1986.
Astronomy and Astrophysics
Astronomy
7
Giant Stars, M Stars, Spectral Line Width, Stellar Mass Ejection, Stellar Motions, Stellar Oscillations, Astronomical Photometry, Atmospheric Heating, Chromosphere, Data Reduction, Iue, Stellar Envelopes, Ubv Spectra
Scientific paper
Analysis is presented of time-series, high dispersion spectra of the Mg II, k, Ca II H, and K lines of the semiregular giants Rho Per (M4 II-III, periodicity of about 50 days), R Lyr (M5 III, period of about 46 days), and g Her (M6 III, period of about 90 days). The fine error sensor on the IUE satellite and ground based UBV photometry was used to relate line profile variations to photospheric variations. The above mentioned stars were selected to study the relative importance of convective motions and global stellar pulsations in determining the structure of the outer atmospheres. Small amplitude changes, but substantial changes in the profiles of Mg II and Ca II lines were detected. It is contended that the observed variability is due to changes in chromospheric conditions and not variations within the circumstellar shell. The picture of a steady state chromosphere, which is modulated on long time scales, is corroborated by these observations. Localized heating is found in g Her.
Cuntz Manfred
Judge Philip G.
Luttermoser Donald G.
Neff Daniel H.
Stencel Robert E.
No associations
LandOfFree
Line profile variations in M giants - Clues to mass-loss and chromospheric heating mechanisms does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Line profile variations in M giants - Clues to mass-loss and chromospheric heating mechanisms, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Line profile variations in M giants - Clues to mass-loss and chromospheric heating mechanisms will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1851589