Loading...
Please wait, while we are loading the content...
Similar Documents
A survey of mg ii h and k emission in near-solar type stars
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Doherty, L. R. |
| Copyright Year | 1984 |
| Description | International Ultraviolet Explorer measurements of Mg II h and k emission fluxes are presented for 30 F and G stars that are on or near the main sequence and compared with Wilson's measurements of the Ca II H and K fluxes in these stars. The survey includes a large proportion of stars with very low chromospheric activity as well as 111 Tau, X(1) Ori and other examples of strong chromospheric emission. Emission cores are presented in all of the stars observed. A sharp lower limit to the flux in the cores of the k lines implies the existence of a minimum level of chromospheric activity in which the k line flux is a constant fraction of stellar luminosity. Reduction of Wilson's values to absolute fluxes produces a close correlation between Mg and Ca strength with possibly some dependence on color. For the most active stars, the Mg k and Ca fluxes are consistent with the presence of solar plage covering up to one half of the stellar surface. However, the ratio of k to h in these stars is much less than this simple interpretation predicts. |
| File Size | 805980 |
| Page Count | 19 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19850013959 |
| Archival Resource Key | ark:/13960/t8jd9q42z |
| Language | English |
| Publisher Date | 1984-12-28 |
| Access Restriction | Open |
| Subject Keyword | Astronomy Stellar Spectra Stellar Color Chromosphere Stars Ultraviolet Spectra G Stars Iue Stellar Radiation Stellar Rotation Magnesium Flux Rate Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
