SUMMARY OF PROPOSAL 63001

DR. GIANPIERO TAGLIAFERRI
GTAGLIAF@MERATE.MI.ASTRO.IT

BRERA ASTRONOMICAL OBSERVATORY
VIA E. BIANCHI 46
MERATE
LECCO ITALY I-22055
Tel: 39 39 9991127 Fax: 39 39 9991160
Medium: 2GBDAT
Subject: STARS

ASCA OBSERVATION OF HD9770: A NEW SHORT-PERIOD ECLIPSING BINARY SYSTEM


ABSTRACT

We propose to observe the short period eclipsing binary system HD 9770 for three consecutive rotation periods. We already observed this newly discovered eclipsing binary with BeppoSAX, detecting both flare activity and rotational modulation of the X-ray light curve. With ASCA we will map the eclipse rotational modulation, disentangling the short-term flare variability from the variability due to rotation modulation. This observing strategy and ASCA spectral capability will allow us to study the coronal structures. Thanks to its very short period and strong activity HD9770 offers a unique opportunity to monitor more contiguous orbital cycles. These data, compared with the BeppoSAX ones, will give us crucial answers on matter such as metal abundance deficiencies and coronal structure size.

CO-INVESTIGATORS
CO-I NAME INSTITUTE COUNTRY
STEFANO COVINOBRERA OBSERVATORYITALY
GIUSEPPE CUTISPOTOCATANIA OBSERVATORYITALY
MARTIN KURSTERESO - LA SILLACHILE
ROBERTO PALLAVICINIPALERMO OBSERVATORYITALY

TARGETS

TARGET NAMEPRIRADECTIMETCOFFGISSIS CNTOBS
1)HD9770
2
23.7533-29.9047 70 ksN
N
P
0.57000
1

TARGET 1

THIS OBSERVATION IS NOT TIME CRITICAL. HOWEVER, IF POSSIBLE, IT WOULD BE DESIRABLE TO START THE OBSERVATION AT PHASE 0.8 (PHASE 0.0 PRIMARY ECLIPSE). THE PHASE IS HJD=2449311.3731+0.476533E