Introduction of the Soft X-ray Imager (SXI) on board the Astro-H - PowerPoint PPT Presentation

Introduction of the Soft X-ray Imager (SXI) on board the Astro-H satellite H. Matsumoto (Kyoto Univ.) on behalf of the SXI team April 28, 2009 IACHEC H. Matsumoto 1

The SXI team • PI: H. Tsunemi (Osaka Univ.) – Osaka Univ.: K. Hayashida, N. Anabuki, H. Nakajima – Kyoto Univ.: T. Tsuru, H. Matsumoto – ISAS/JAXA: T. Dotani, M. Ozaki, A. Bamba – Kogakuin Univ. : T. Kohmura – Rikkyo Univ.: H. Murakami – RIKEN: J. Hiraga – Miyazaki Univ. : K. Mori, M. Yamauchi – Noqsi: J. P. Doty – MIT: M. W. Bautz April 28, 2009 IACHEC H. Matsumoto 2

Soft X-ray Imager (SXI) SXI = X-ray CCD • Requirements – Imaging capability for compensating the calorimeter (Soft X-ray Spectrometer; SXS) – Bridging the dynamic ranges of the SXS(0.3—10keV) and of the Hard X-ray Imager (HXI; 5—80keV) •Wide dynamice range: 0.2 – 20 keV •Low background: similar to the Suzaku X-ray CCD (XIS) April 28, 2009 IACHEC H. Matsumoto 3

From XIS (Suzaku) to SXI (ASTRO-H) XIS SXI •4 cameras •1 camera •1 chip/camera •4 chips/camera •FOV 18arcmin □ •FOV 38arcmin □ •MIT/Lincoln chip •HPK chip •Nch CCD •Pch CCD •FI and BI •BI •Temp -90 ℃ •Temp -120 ℃ •Peltier Cooler •Stirling Cooler •Optical Blocking Filter •Optical Blocking Layer April 28, 2009 IACHEC H. Matsumoto 4

X-ray CCD chip of SXI Spec (manufacturer : Hamamatsu Photonics) � Pch back-illuminated CCD (carrier = hole) � Depletion layer is > 200 μ m � 4 chip mosaic � 1 chip Pixel : 24 μ m □、 1280x1280 、 1 CCD chip 30.72mm □ � FOV 38arcmin □ (Focal Length ~ 5.6m) � Optical Blocking layer (Al - PI – Al) on the chip � Chip gap (dead area) : >0.6mm We need off-set the bore-sight by 5x5mm. � SCI technique (Charge injection) is employed. April 28, 2009 IACHEC H. Matsumoto 5

CCD current status Spectrum of 55Fe Detection Effificency FWHM 135+/-4eV@6keV Noise 5.6 +/- 0.1 e- X-rays from 109Cd April 28, 2009 IACHEC H. Matsumoto 6

Overall view of the SXI camera Analog Elec Stirling Cooler April 28, 2009 IACHEC H. Matsumoto 7

Optical Blocking Layer (OBL) • Specification – Optical/UV light is blocked – Eliminate the thin plastic film (OB Filter) to avoid the vacuum system . • Al 400 Å Polyimide 1000~2000 Å OBL Al 1000 Å CCD April 28, 2009 IACHEC H. Matsumoto 8

Efficiency and Effective Area SXI (with OBL) SXI + XRT April 28, 2009 IACHEC H. Matsumoto 9

SXI System SXI PSU SXI PSU SXI FrontEnd SXI-S Temp Control SXI-E Heater HeaterPow HeaterPow Temp monitor HK HK ADC HK ADC SXI-DE memory memory memory memory CCD CCD 電圧/温度モニタ CPU Sequencer Cmd I/F Sequencer Cmd I/F FPGA FPGA FPGA Inter-board bus FPGA SOI SOI ① Drive clock ② ③ SOC Pixel CODE SOC CCD Driver CCD Driver ( DAC + Analog SW) ( DAC + Analog SW) DE/IF SpW DE/IF SpW SpW SpW Frame data FPGA FPGA FPGA FPGA Video ASIC FPGA FPGA Video ASIC Command memory Δ∑ modulator & decimation filter memory frame data Space dark level process event SXI-A memory event extraction memory Card candidates Universal SpW Module x2 ① Driver DAC set ② High/Low Switching * Hardwares of DE I/F board and ③ PreAmp gain、Pump DAC set April 28, 2009 IACHEC H. Matsumoto 10 sequencer board are identical & ASIC timing ver.20080408

Calibration plan • Screening process will begin this fall. – Optimize parameters such as voltage etc. – OBL, noise, bad pixels etc.. • Calibrations of flight sensors will begin in spring, 2012. – At Osaka Univ. (soft-energy band) and Kyoto Univ. (hard-energy band) – QE, energy resolution • How to calibrate QE of BI sensor with OBL? April 28, 2009 IACHEC H. Matsumoto 11