SUMMARY OF PROPOSAL 52011
SMITHSONIAN ASTROPHYSICAL OBSERVATORY
60 GARDEN STREET
CAMBRIDGE
MA USA 02138
Tel: 617 496 7850 Fax: 617 495 7356
Medium: 4GBDAT
Subject: STARS
KSI UMA AND THE FIP EFFECT VS METAL POOR CORONAE CONUNDRUM
ABSTRACT
ASCA and EUVE spectra of active single stars, RS CVn's and Algol binaries show highly active coronae to be depleted in metals relative to the photosphere by factors of ~2-10. In contrast, spectra of lower activity stars like the Sun exhibit the "FIP Effect" in which elements with low first ionization potential (FIP), such as Fe, are enhanced relative to the photoshere - a totally opposite effect! Simultaneous ASCA and EUVE observations of the X-ray brightest intermediate activity star ksi UMa B would provide the first measure of coronal abundance anomalies at the missing key intermediate activity level, completing the picture of coronal abundance anomalies from low to high activity levels and telling us whether or not the metal poor and FIP Effect coronae are related.
CO-INVESTIGATORS
| CO-I NAME | INSTITUTE | COUNTRY |
|---|
| STEPHEN DRAKE | NASA GSFC | USA |
| MARTIN LAMING | NAVAL RESEARCH LAB | USA |
TARGETS
| TARGET NAME | PRI | RA | DEC | TIME | TC | OFF | GIS | SIS CNT | OBS |
|---|
| 1)KSI UMA | 1 | 169.5521 | 31.5375 | 50 ks | N | N | P | 2.50000 | 1 |
TARGET 1
OBSERVATION SIMULTANEOUS WITH EUVE. CO-ORDINATION WILL BE DONE IN THE EUVE SCHEDULE: NO TIME CONSTRAINT IS PLACED ON THE ASCA OBSERVATION, OTHER THAN IT BE OBSERVED BEFORE 3 MARCH 1997