Astronomy and Astrophysics – Astronomy
Scientific paper
Oct 1980
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1980apj...241..759s&link_type=abstract
Astrophysical Journal, Part 1, vol. 241, Oct. 15, 1980, p. 759-773.
Astronomy and Astrophysics
Astronomy
71
Atmospheric Models, Chromosphere, K Stars, Stellar Atmospheres, Stellar Models, Stellar Spectra, Ultraviolet Spectra, Binary Stars, H Alpha Line, Iue, K Lines, Late Stars, Spaceborne Astronomy, Spectrum Analysis
Scientific paper
IUE spectra in the region 1150-3200 A of the RS CVn-type variables HR 1099 and UX Arietis are presented and analyzed in terms of chromospheric models. Measurements of Mg h and k lines and Ca II H-K and H alpha spectra are indicated which are found not to be correlated with orbital phase or radio flares and which suggest that the strong emission arises in the K star rather than the G star in these systems. Under the assumption that the UV emission lines are associated with the K star, surface gravities of log g = 3.6 and 3.4 and effective temperatures of 4850 and 5000 K are adopted for HR 1099 and UX Ari, respectively, along with solar metal abundances for each. Model calculations of the chromospheric structure necessary to account for observed C(+), Mg(+), Si(+) and Si(+2) line fluxes are presented which indicate that the transition region pressure lies in the range 0.18-1.0 dynes/sq cm, implying transition regions that are more extended than that of the sun and are not conductively heated. It is noted that pressure scaling laws and the use of Mg II and C II lines as pressure diagnostics may be invalid, possibly due to atmospheric inhomogeneities or gas flows.
Linsky Jeffrey L.
Simon Theodore
No associations
LandOfFree
IUE ultraviolet spectra and chromospheric models of HR 1099 and UX ARIETIS 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 IUE ultraviolet spectra and chromospheric models of HR 1099 and UX ARIETIS, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and IUE ultraviolet spectra and chromospheric models of HR 1099 and UX ARIETIS will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-947679