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

April 28, 2009 IACHEC

• H. Matsumoto

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Introduction of the Soft X-ray Imager (SXI) on board the Astro-H satellite

• H. Matsumoto (Kyoto Univ.)
• n behalf of the SXI team

April 28, 2009 IACHEC

• H. Matsumoto

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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

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Soft X-ray Imager (SXI)

• 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)

SXI = X-ray CCD

• Wide dynamice range: 0.2 – 20 keV
• Low background: similar to the Suzaku X-ray CCD (XIS)

April 28, 2009 IACHEC

• H. Matsumoto

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From XIS (Suzaku) to SXI (ASTRO-H)

XIS

• 4 cameras
• 1 chip/camera
• FOV 18arcmin□
• MIT/Lincoln chip
• Nch CCD
• FI and BI
• Temp -90℃
• Peltier Cooler
• Optical Blocking Filter

SXI

• 1 camera
• 4 chips/camera
• FOV 38arcmin□
• HPK chip
• Pch CCD
• BI
• Temp -120℃
• Stirling Cooler
• Optical Blocking Layer

April 28, 2009 IACHEC

• H. Matsumoto

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X-ray CCD chip of SXI

Spec (manufacturer : Hamamatsu Photonics)

Pch back-illuminated CCD (carrier = hole) Depletion layer is > 200μm 4 chip mosaic 1 chip Pixel : 24μm□、1280x1280、 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. 1 CCD chip

April 28, 2009 IACHEC

• H. Matsumoto

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CCD current status

Spectrum of 55Fe FWHM 135+/-4eV@6keV Noise 5.6 +/- 0.1 e- X-rays from 109Cd Detection Effificency

Overall view of the SXI camera

April 28, 2009 IACHEC

• H. Matsumoto

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Analog Elec Stirling Cooler

Optical Blocking Layer (OBL)

• Specification

– Optical/UV light is blocked – Eliminate the thin plastic film (OB Filter) to avoid the vacuum system.

• April 28, 2009 IACHEC
• H. Matsumoto

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CCD

Al 1000Å Al 400Å Polyimide 1000~2000Å

OBL

Efficiency and Effective Area

April 28, 2009 IACHEC

• H. Matsumoto

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SXI (with OBL) SXI + XRT

April 28, 2009 IACHEC

• H. Matsumoto

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CCD CCD

SXI System

dark level process event extraction

DE/IF FPGA DE/IF FPGA * Hardwares of DE I/F board and sequencer board are identical

Pixel CODE Δ∑ modulator & decimation filter frame data event candidates memory memory Command

① Driver DAC set ② High/Low Switching ③ PreAmp gain、Pump DAC set & ASIC timing

SOI SOC SOI SOC

memory memory

Space Card

memory memory memory memory 電圧/温度モニタ Temp Control HK CPU

SXI PSU SXI PSU ③ ② ①

SXI-E SXI-A

HeaterPow HeaterPow

Cmd I/F

FPGA

Cmd I/F

FPGA

Drive clock

Sequencer

FPGA

Sequencer

FPGA Heater

Temp monitor

SpW FPGA SpW FPGA SpW FPGA SpW FPGA

Inter-board bus

Universal SpW Module x2 SXI FrontEnd

HK ADC HK ADC CCD Driver

( DAC + Analog SW)

CCD Driver

( DAC + Analog SW)

Video ASIC Video ASIC

ver.20080408

SXI-DE SXI-S

Frame data

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

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