VERIFYING THE NUMERICAL RADIATIVE TRANSFER CALCULATION USING AN ACCRETION DISK CORONA SOURCE
In most XRISM programs to come, spectral lines observed with Resolve are formed in the NLTE conditions. For proper interpretations of the observed spectra, spectral synthesis based on the numerical radiative transfer calculation is a requisite. Currently, however, no RT code is reliable enough to compare to the observed data in the X-rays. What we should do now is to benchmark the numerical RT calculations against the actual observations. We demonstrated that this approach is productive for the soft X-ray band using XMM-Newton grating spectra of an ADC hosting a WD. We propose to observe 4U 1822 370, an ADC hosting a NS with Resolve to extend our study to hard X-rays. The goal of this observation is to record the high-quality spectrum to be used for benchmarking RT calculations.
TELESCOP= 'XRISM ' / Mission name INSTRUME= 'RESOLVE ' / Instrument name FILTER = 'OPEN ' / Filter name used OBS_ID = '201000010' / Observation identification string OBJECT = '4U1822-371' / Object name OBSERVER= 'MASAHIRO TSUJIMOTO' / PI name OBS_MODE= 'POINTING' / POINTING or SLEW or ALL RA_OBJ = 276.4451 / [deg] Object Right ascension DEC_OBJ = -37.1051 / [deg] Object Declination RA_PNT = 276.43974742027 / Pointing RA DEC_PNT = -37.1052415963486 / Pointing DEC RA_NOM = 276.444856861301 / [deg] Nominal aspect point R.A. DEC_NOM = -37.1049229596857 / [deg] Nominal aspect point Dec. PA_NOM = 92.1047386688104 / [deg] Nominal aspect point roll. TELAPSE = 232653.969547987 / Elapsed time DATE-OBS= '2025-04-12T18:02:54' / Start date DATE-END= '2025-04-15T10:40:27.969548' / Stop date ONTIME = 124681.01076 / On-source time EXPOSURE= 124681.01076 / Exposure time PROCVER = '03.00.013.010' / 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= 'gen20241115_xtd20241115_rsl20241115' / Version of CALDB used DATE = '2025-04-22T06:59:23' / Date and time this file was created or updated SIB2_VER= 'V03.01 ' / SIB2 version JAXA