1. Soft x-ray properties of XIS FI and BI CCD onboard Astro-E2 (SUZAKU)
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Soft x-ray properties of XIS FI and BI CCD onboard Astro-E2 (SUZAKU)
K. Hayashida, K. Torii, M. Namiki, S. Katsuda, M. Shoji, T. Miyauchi, D. Matsuura, H. Tsunemi (Osaka Univ, Japan);
T. Kohmura (Kogakuinn Univ, Japan);
H. Katayama, (JAXA, Japan) and
the SUZAKU XIS team
©ISAS/JAXA

2. XIS Components XIS-Sensors AE/TCE DE CCID41-FI CCD
EU (Engineering Unit)
FM FI0,FI1,FI2,FI3
CCID41-BI CCD
FM BI0,BI1
AE/TCE
FM AE/TCE01,23
EM AE/TCE DE
FM 4PPU+MPU
*)FM Spare before Launch

3. Calibration Task Share
Components
Location
X-ray Source
QE reference
Chip level
CSR/MIT
Fluorescent X-rays (C,O,F,Al,Si,P,Ti,Mn,Cu)
ACIS chips calibrated at BESSY
Camera without OBF
+FM AE
Osaka
Grating Spectrometer
keV
Polypro-window Gas PC & XIS-EU
Kyoto
Fluorescent X-rays (Al,Cl,Ti,Mn,Fe,Zn,Se)
Window-less SSD
OBF
Synchrotron Facility
Synchrotron X-rays + monochrometer
(Transmission measurement with PIN diode)
Camera onboard the satellite
ISAS/JAXA
55Fe

4. XIS Data Reduction Frame Data /8sec Event data
XIS Response depends on the reduction procedure
Frame Data /8sec
Dark-level Subtraction
Event Pickup (PH(E)>Event Threshold)
5x5 mode, 3x3 mode or 2x2 mode
Event data
Charge Trail Correction
Grading / PHA-reproduction for PH(i)>Split Threshold
PHA-dependent Split Threshold for BI
Bad Columns Filter
Spectrum / Image / Light Curve
Onboard DE
* :Newly introduced
On the ground

5. Charge Trail ＰＨ（２）= preceding pixel ，ＰＨ（７）=trailing pixel
BI1 5.9keV X-ray incidence
PH [ADU]
RAWY a b
Near readout node d c b
Far from readout node a c d

6. Grade branching Ratio （ＢＩ１）
Before the Charge Trail Correction
After the Charge Trail Correction

7. Optimization of Split Threshold for BI1
G02346 event number
FWHM (eV)
Spth (ADU)

8. PHA-dependent SpTh
PHA-dependent Split Threshold for BI

9. Calibration Facility in the Osaka Clean Room
Detector Chamber
Manson Soft X-ray Generator
Hetrick Spectrometer

10. Dispersion (Grating) Spectrum
projection
X-ray image
X-ray energy
FWHM～5eV
O-Kα（0.53keV）
こちらがCCDで得られたX線画像です。分散X線が上下方向に当たっています。低エネルギーほど下に分散されていまして、CCDのこの方向の位置とエネルギーは１対１に対応しています。このような明るい筋は、特性X線に対応しています。これを分散方向にプロジェクションしたのがこちらの図です。このようにして得たエネルギースペクトルは、CCDで得られるイベントのエネルギー情報よりもはるかに優れたエネルギー分解能のスペクトルが得られます。このスペクトルを我々は分散スペクトルと呼びます。以降、この分散スペクトルをもとに解析を行いました。
C-Kα (0.28keV)
Dispersion direction
Number of events/columns

11. Line profile against O-K line incidence
Astro-E1 (FI) XIS
Astro-E2 (FI) XIS
5 kV
FI2
PHA(ADU)
XIS1 (H.Katayama master thesis)

12. Four components model for monochromatic X-ray
（１）　Main peak: photoabsorption in depletion layer
（２）　Sub peak: charge loss below the split threshold
（３）　Triangle: channel stop
（４）　Constant: SiO2 Layer F3
Parameters：
T1 (normalization), C1(center), S1(sigma)
T2 (relative to T1), C2(spth/2, fixed), S2 (1.78×S1, fixed)
T3 (relative to T1), F3(Triangle width, 0.5×C1)
T4 (relative to T1)　→　6 free parameters
Structure of BI chip （MIT）

13. Oxygen-K (E=525eV) Line ProfileBI
S1: 4.7ch~7.7%(FWHM)
T2: 0.039
T3<1.8e-3
T4=6.5e-3
S1: 5.1ch~9.0%(FWHM)
T2: 0.030
T3<2.9e-4
T4=1.1e-2
Pulse Height
Pulse Height
Both FI and BI spectra are well reproduced by the 4 component model.

14. 55Fe Line Profile
FI3
BI1
Energy [keV]
Energy [keV]
In addition to the 4 components model, Si-K escape and Si-K fluorescence lines are included.

15. Ex-PH Relation (Linearity)BI FI
Energy [keV]
Energy [keV]

16. Ex-PH Relation (Low Energy Region)FI BI
Energy [keV]
Energy [keV]

17. Quantum Efficiency (QE)
XIS-FM(FI0)
Gas PC
XIS-EU(FI)
XIS-FM(FI2)
XIS-FM(FI3)
Absolute QE by slant incident method
Relative QE measurement using Grating Spectrometer
XIS-FM(BI1)
CCD design value
Relative QE among XIS were accuratly measured.
Reference of the Absolute QE can be either
QE of the gas PC for which we conducted slant incident measurement.
QE calculated from the design value of XIS BI-CCD, of which QE is close to 1.
Comparing both results will show systematic error of the absolute QE of XIS-FMs.

18. Slant Incident Method: Application to Gas PC
X-rays
X-rays
We determined to use the Gas PC as the reference counter

19. Ratio of Counting rate of Gas PC
30°/0°
45°/0°
Best fit estimate
Poly propylene thickness
1.01±0.06mm
H2O
0.281±0.048mm
P10gas dead layer
79.6±9.7mm

20. XIS-EU and Gas PC cross calibration using a entrance slit

21. PC Spectra and CCD Spectra
PC (0.525keV)
XIS-EU (0.525keV)

22. QE(PC)->QE(EU)->XIS BI1 QE
-1deg offset slant-PC is assumed
Best Fit Estimates
HfO2
0.005mm fixed Ag
0.001mm fixed
SiO2
0.000±0.0005mm
Si depletion
43.6±0.7mm
Constant Factor
0.961±0.003
Some data points exceeds 1
Difficult to reproduce 0.28keV QE with simple absorption models.
At low energy side, artificial cutoff in the form of erf(Ex) is introduced.
This model QE is used as a new reference.

23. FI2 QE (QE(FI2)/QE(BI1))x BI1-QE-model =>QE(FI2) Best Fit Estimates
SiO2
0.440±0.004mm Si
0.288±0.004mm
Si3N4
0.026mm fixed　
Si depletion
70.4±1.5mm
Constant Factor
1.00 fixed
(QE(FI2)/QE(BI1))x BI1-QE-model =>QE(FI2)
Detailed gate structure is taken into account

24. XAFS near the O-Kedge FI-2 Eedge = 0.532 ±0.001 keV red. c2 = 1.3178
(d.o.f. = 418)

25. Soft X-ray Transmission of OBFs were separately measured.
Kitamoto et al., 2003, NIMA 505,p683

26. SUZAKU Lauch M-V 6 rocket
©ISAS/JAXA
SUZAKU
Lauch M-V 6 rocket
12:30 JST July 10, 2005
From USC, Japan
Orbit ~560km nearly Circle after deltaV operation was established.
Extensible Optical Bench was deployed.
3axies attitude control system are working.
All the detector systems (XRS,XIS,HXD) were powered on. Initial operations to set up detectors is now going in order to start real observation from mid August.

27. Current XIS status
Jul 25th: 1st CCD frame data from all the four cameras.
Jul 27th1:CCDs was cooled down to -90degC (nominal temp) with TECs.
Various clocking mode (timed exposure, parallel sum etc.) are beeing tested.
Parameters for on-board digital processing on are now beeing tuned. (Dark level determination parameter etc.)
Doors will be opened on Aug3rd to get 1st light. Target is TBD.
XIS0 frame data
-90degC on Jul27th
55Fe event + Cosmic Rays

28. Clibration Source 55Fe Spectra
2005Jul28 14:35- 8sec x 607 frames
CCD = -90degC, timed exposure.
55Fe calibration sources are mounted on the door of the cameras, which will not be availale after the door open.
MnKa FWHM(eV) obtained
camera quadＡ quadB quadC quadD
XIS FI
XIS BI
XIS FI
XIS FI
PHA (XIS FI0 quadrantA)
by H. Yamauchi
All the CCDs and their readouts, and Analog, Digital electronics are working properly. Parameter tuning for on board digital processing is under going, which will improve FWHM slightly.

29. Summary
We have completed the calibration experiments on the ground for XIS flight models.
Data reduction procedures were upgraded for SUZAKU XISs.
1st version of the response matrices are ready (QE, Ex-PH, spectral profile).
XIS are working properly in the orbit. We all hope to get beautiful 1st light image.