SUMMARY OF PROPOSAL 82023
GSFC/USRA
CODE 662 GSFC
GREENBELT
MD USA 20771
Tel: 301-286-5576 Fax: 301-286-1629
Medium: CD ROM
Subject: STARS
THE COLLIDING WIND BINARY WR 140: X-RAY EMISSION AND ABSORPTION VARIATIONS DURING APPROACH TO PERIASTRON
ABSTRACT
We propose to crown our semi-annual \ASCA\ monitoring program of the touchstone colliding-wind 7.94-year binary star WR140 (WC7+O) with a detailed series of \ASCA\ observations just prior to the 2001.14 periastron passage. Because of the high eccentricity, both emission and absorption are predicted to evolve very rapidly near periastron. A long look with \ASCA\ provides the first chance ever to observe in detail the change in $L_{x}$ and $N_{H}$ to allow critical tests of numerical hydrodynamic models. Of particular interest is to determine whether the rapid changes seen in the X-ray flux from $\eta$ Car near its putative ``periastron passage'' are also seen in WR 140.
CO-INVESTIGATORS
| CO-I NAME | INSTITUTE | COUNTRY |
|---|
| ANDY POLLOCK | C&S LTD | UK |
| IAN STEVENS | BIRMINGHAM | UK |
| THE XMEGA GROUP | VARIOUS | USA |
TARGETS
| TARGET NAME | PRI | RA | DEC | TIME | TC | OFF | GIS | SIS CNT | OBS |
|---|
| 1)WR 140 | B | 305.1162 | 43.8545 | 750 ks | N | N | P | 1.60000 | 1 |
| 2)WR 140 | B | 305.1162 | 43.8545 | 250 ks | N | N | P | 3.00000 | 1 |
TARGET 1
DURING FIRST OBSERVING WINDOW (15 APR 2000 TO 08 JUL 2000)
TARGET 2
DURING SECOND OBSERVING WINDOW (30 SEP 2000 TO 20 DEC 2000)