SUMMARY OF PROPOSAL 52007
SMITHSONIAN INSTITUTION ASTROPHYSICAL OBSERVATORY
60 GARDEN STREET
CAMBRIDGE
MA USA 02138
Tel: 617 495 7489 Fax: 617 495 7049
Medium: 4GBDAT
Subject: STARS
AR LAC: HIGH T STRUCTURE AND ABUNDANCES
ABSTRACT
We propose to observe the eclipsing binary AR Lac with ASCA and EUVE simultaneously, to determine the temperature structure, abundances, and location and size of coronal emitting regions. Combined ASCA and EUVE spectroscopy uniquely provides complete coverage of temperatures from 1 to 100 million K. Lightcurve analysis using the ASCA and the EUVE-DS will allow separation of the temperature dependence of variable features from the spectral dependence. An ASCA spectrum can establish the presence of a high energy ``tail'' in the DEM. We request one complete binary period, plus an optional request for coverage of a second cycle. Additional coverage will allow the first measure of cycle to cycle variability in the orbital lightcurve, and extend through the EUVE observations.
CO-INVESTIGATORS
| CO-I NAME | INSTITUTE | COUNTRY |
|---|
| NANCY BRICKHOUSE | SAO/CFA | USA |
| STEPHEN DRAKE | LHEA/GSFC | USA |
| NICHOLAS WHITE | LHEA/GSFC | USA |
| KHULINDER SINGH | TATA/BOMBAY | INDIA |
| MAREK SIARKOWSKI | SRC/POLISH ACADEMY | POLAND |
TARGETS
| TARGET NAME | PRI | RA | DEC | TIME | TC | OFF | GIS | SIS CNT | OBS |
|---|
| 1)AR LAC NO 1 | 1 | 332.1700 | 45.7423 | 80 ks | Y | N | P | 2.00000 | 1 |
TARGET 1
THIS OBSERVATION IS TO BE COORDINATED WITH EUVE. A SECOND WINDOW OF AVAILABILITY IS 1997 11 13 0 0 TO 1997 12 13 0 0.
COORDINATED OBSERVATION: START: Jun 20,1997 at 00STOP: Jul 29,1997 at 00