DYNAMIC CHANGE OF ACCRETION STRUCTURE IN THE YOUNGEST X-RAY BINARY CIRCINUS X-1 HOSTING A WEAKLY MAGNETIZED NEUTRON STAR
The peculiar X-ray binary Circinus X-1 hosts a weakly magnetized neutron star and B5-A0 supergiant. Discovery of a natal supernova remnant makes Circinus X-1 the youngest X-ray binary hosting a neutron star in our Galaxy. Around the periastron passage, different types of X-ray flares, originating from disk or wind accretion, have been found with rich Fe-line structures, P-Cygni, emission, absorption, and edge features. XRISM provides accretion geometry and stellar wind information of this new-born peculiar binary.
TELESCOP= 'XRISM ' / Mission name INSTRUME= 'XTEND ' / Instrument name OBS_ID = '300028010' / Observation identification string OBJECT = 'Circinus_X-1' / Object name OBSERVER= 'XRISM Collaboration' / PI name OBS_MODE= 'POINTING' / POINTING or SLEW or ALL RA_OBJ = 230.17021 / [deg] Object Right ascension DEC_OBJ = -57.16669 / [deg] Object Declination RA_PNT = 230.1439851983 / Pointing RA DEC_PNT = -57.1689282049026 / Pointing DEC RA_NOM = 230.17057153652 / [deg] Nominal aspect point R.A. DEC_NOM = -57.1664748851418 / [deg] Nominal aspect point Dec. PA_NOM = 103.993381183015 / [deg] Nominal aspect point roll. TELAPSE = 65818.765625 / Elapsed time DATE-OBS= '2024-02-15T06:32:51.234375' / Start date DATE-END= '2024-02-16T00:49:50' / Stop date ONTIME = 26215.153158 / On-source time EXPOSURE= 26215.153158 / Exposure time PROCVER = '03.00.013.009' / Processing script version MKFFF = 'ISAS/JAXA' / Origin of First FITS file ORIGIN = 'GSFC/NASA' / Origin of Processed FITS file SOFTVER = 'Hea_21Aug2024_V6.34_XRISM_21Aug2024_V001' / Version of HEADAS used CALDBVER= 'gen20240315_xtd20240815_rsl20240815' / Version of CALDB used DATE = '2024-09-24T01:04:41' / Date and time this file was created or updated SIB2_VER= / SIB2 version JAXA