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HXMT Coordinated Observation Shaolin XIONG On behalf of HXMT SGS team Institue of High Energy Physics, China 11th IACHEC, IUCAA, PUNE (Mar 1, 2016). In-flight calibration (1): PSF. High Energy tel. NaI/CsI 20-250 keV, ~5000 cm2 Medium Energy tel. Si-PIN 5-30 keV, ~950 cm2
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HXMT Coordinated ObservationShaolin XIONGOn behalf of HXMT SGS teamInstitue of High Energy Physics, China11th IACHEC, IUCAA, PUNE (Mar 1, 2016)
In-flight calibration (1): PSF High Energy tel. NaI/CsI 20-250 keV, ~5000 cm2 Medium Energy tel. Si-PIN 5-30 keV, ~950 cm2 Low Energy tel. SCD (CCD236) 1-15 keV, ~380 cm2 • Collimators for HE/ME/LE • Scan the constant bright 'point' source (Crab or PSR B1509-58) • Crab exposure: ~ 40 ks • Crab is visible from Sep. to Mar.
In-flight calibration (2)(3): RMF, ARF; Timing High Energy tel. NaI/CsI 20-250 keV, ~5000 cm2 Medium Energy tel. Si-PIN 5-30 keV, ~950 cm2 Low Energy tel. SCD (CCD236) 1-15 keV, ~380 cm2 • RMF&ARF • Absolute ARFs need to be calibrated in-flight • Pointing observing the Crab or other sources cross calibrated with others • Adjust RMF and ARF to fit the observed data with the “known” source spectrum • Timing • Observe the Crab/PSR B1509-58 • 10ks for Crab, 1Ms for PSR B1509-58
In-flight calibration (4): Energy-Channel and FWHM • HE • AGC with 241Am (1/det. unit) • Temp. range : 18 ± 2 °C • ME • 241Am (2/det. box) • Temp. range:-50 ~ 0 °C • LE • 55Fe (1/det. box) • Temp. range:-80 ~ -30 °C Fluorescent lines (73Ta)in HE Gain & FWHM varies with Temp. • Measured on ground Calibration Sources • Radioactive sources on-board • Fluorescent lines • Sources with line features (1 – 30 keV) Tycho Spectrum Fe Kα Line, 126ks(3 σ) obs is needed 4
In-flight calibration (5): Bkg model • Cross calibrate the blank sky (~ deg)? • CXB is anisotropic • Especially for LE (< 7 KeV) where CXB dominates the BKG Known sources and Blank sky (blue circle for HXMT, red circle for RXTE)
In-flight calibration (6): Response of the spacecraft • GRB monitor • Use CsI (200 keV - 3 MeV) detector of HE • Approximately all-sky monitoring • Energy response calibration will not be calibrated on ground • Simultaneous GRBs by Fermi, Swift, Integral, Konus-Wind, etc. GRB GRB
List of In-flight Calibration Sources • Other (IACHEC) sources? • HXMT Initial Calibration phase: 2016.12 – 2017.2 (TBC) 7
HXMT visibility to some sources Blank sky 8