SUMMARY OF PROPOSAL 61043

PROF. FUMIAKI NAGASE
NAGASE@astro.isas.jaxa.jp

ISAS
KANAGAWA JAPAN 229
SAGAMIHARA
3-1-1 YOSHINODAI
Tel: 0427-51-3911(X2611) Fax: 0427-59-4253
Medium: 2.5GB8MM
Subject: X-RAY BINARIES

ASCA FOLLOW-UO OBSERVATIONS OF ANOMALOUS 6-S X-RAY PULSERS


ABSTRACT

Recently it has become evident that there is a small subgroup of X-ray pulsars, with pulse periods close to 6 sec. These pulsers are characterized by the very steep soft spectrum, relatively low lominosity and secular spin-down trend. 4U0142+61, 1E2259+586, and 1E1048.1-5937 are the typical example of this subclass and they were once observed with ASCA in 1993 to 1994. Currently the most likely interpretation is that these pulsars are single neutron stars accreting matter from a disk, the recent remnants of the common-envelope evolution of a high-mass X-ray binary. We propose that the observations of these pulsar with ASCA again in five years' interval is crucially effective to examine the currently proposed hypotesis for the origin of this cluss pulsars.

CO-INVESTIGATORS
CO-I NAME INSTITUTE COUNTRY
MUTSUMI SUGIZAKIISASJAPAN
TAKAO ENDOISASJAPAN
TADAYASU DOTANIISASJAPAN

TARGETS

TARGET NAMEPRIRADECTIMETCOFFGISSIS CNTOBS
1)4U 0142+61
3
26.5917 61.7510 20 ksN
Y
P
1.00000
1
2)1E 1048.1-5937
3
162.5371-59.8890 40 ksN
Y
P
0.30000
1