SUMMARY OF PROPOSAL 71022

MS YOHKO TSUBOI
TSUBOI@CR.SCPHYS.KYOTO-U.AC.JP

KYOTO UNIV.
KITASHIRAKAWA-OIWAKE-CHO, SAKYO
KYOTO
KYOTO JAPAN 606-8502
Tel: 075-753-3843 Fax: 075-753-3799
Medium: 2.5GB8MM
Subject: STARS

DISCOVERY OF X-RAY FROM BROWN DWARFS


ABSTRACT

We detected X-ray from Brown Dwarf with ROSAT PSPC. Then we confirmed the hard X-ray from the position with ASCA data. There is no other catalogued source in 2 arcmin from the position, then this is the first discovery of X-ray from BD. There is no theory which predicts strong X-ray from BD which is fully convective and has no disk. Accordingly, this discovery will require reformation of X-ray emisison mechanism in stars in general. The most notable meaning of the discovery of X-ray from BD is that it will be powerful tool for BD survey and it will pioneer new field of X-ray astronomy. This goal is to confirm the X-ray from BD and to discover new X-rays from BDs, to obtain the spectra and time variabilities in broad X-ray band, and finaly to investigate the X-ray emission mechanism.

CO-INVESTIGATORS
CO-I NAME INSTITUTE COUNTRY
KATSUJI KOYAMAKYOTO UNIV.JAPAN
KENJI HAMAGUCHIKYOTO UNIV.JAPAN
HIROSHI MURAKAMIKYOTO UNIV.JAPAN
SHIGEO YAMAUCHIIWATE UNIV.JAPAN
RALPH NEUH\"AUSERMPEGERMANY
YOSHITOMO MAEDAJSPSJAPAN

TARGETS

TARGET NAMEPRIRADECTIMETCOFFGISSIS CNTOBS
1)CHAIBROWNDWARFS
B
166.8208-77.5983
100 ks
N
Y
P
0.10000
1