1. Orbital verification of the performance of Suzaku XIS
K. Hayashida, K. Torii, M. Namiki, N. Anabuki, S. Katsuda, N. Tawa, T. Miyauchi, H. Tsunemi, Osaka Univ. (Japan);
H. Matsumoto, T. G. Tsuru, H. Nakajima, H. Yamaguchi, K. Koyama, Kyoto Univ. (Japan);
T. Dotani, M. Ozaki, H. Murakami, H. Katayama, Japan Aerospace Exploration Agency (Japan);
S. Kitamoto, Rikkyo Univ. (Japan); H. Awaki, Ehime Univ. (Japan);
T. Kohmura, Kogakuin Univ. (Japan);
B. LaMarr, E. Miller, S. E. Kissel, M. W. Bautz, R. F. Foster, Massachusetts Institute of Technology

2. X-ray Imaging Spectrometer (XIS)
X-ray CCD Cameras onboard Suzaku
3 Cameras (XIS0,XIS2,XIS3) contains FI-CCD、１ Camera（XIS1) has BI-CCD
CCD Operation Temp = -90℃
1024x1024pixels
FOV18’x18’
Energy Range keV

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. Initial Operation and Current Status
2005/7/10 Suzaku Launch
2005/7/25 XIS System Power On
2005/8/12-8/13 　　　　　　　　　　　　　　　XIS Door Open　　　　　　　　　　　　　　　　　＝First Light
2006/05/31　　　　　　　　　　　　　　　　　　　　More than 100 objects were observed. 4 CCD Cameras are functioning properly. E
JAXA press release

5. ~0.5keV incident BI
Small tail component!

6. Chemisorption Process
Burke et al., 2004, IEEE transactions on Nuclear Science, 51, p.2322

7. すざくXIS 7/10 0パス非可視で電磁バルブの開閉。 7/11 電磁バルブの開（４パス）閉（５パス）。 7/21 温度を上げてバルブ開。
7/10 0パス非可視で電磁バルブの開閉。
7/11 電磁バルブの開（４パス）閉（５パス）。
7/21 温度を上げてバルブ開。
7/24 MPU, PPU立ち上げ。
7/25 AE立ち上げ。データ取得開始（frame mode）
7/26 CCD設定温度：−60℃
7/27 CCD設定温度：−90℃（ノミナル動作温度）
8/11 CCD設定温度： −80℃。HP設定温度： −35℃。
8/12 XIS-3ドア開。
8/13 XIS-2,1,0 ドア開。
Better Energy Resolution at Low Energies

8. Suzaku Team
Compiled by Fujimoto et al.

9. Orbital Calibration Items
Energy Scale
Tracking evolution of Charge Transfer Inefficiency (CTI)
Verification of Energy Scale in orbit
Quantum Efficiency
Verification of QE measured on ground
Monitoring possible change of QE in time
Background
Energy Resolution and Response Profile
Updating Calibration Data Base continuously.
Software tools are also required to be updated.

10. Ex-PHA relation （Calibration on ground）
Residual to straight line fit
Residual to broken line fit
+10eV
-10eV
Si K edge (E=1839 eV)

11. 55Fe Cal-Source→ Gain monitor
Mn-Ka 5.9keV
Mn-Kb
6.5keV
55Fe Cal-Source→ Gain monitor
counts
PH [ch]
Peak ch of Mn-Ka
(Normalized to the ch at 1st ligt)
Energy Resolution
FWHM＠5.9keV
Gain Decrease ~2%/year
Energy Resolution 140eV ->170~180eV
CTI increase induced by orbital radiation damage of the CCD

12. Q’ = Q(1-CTI)N → CTI = (Q- Q’) / Q / N
Determination CTI parameters included in rev0.6 data
Q’ = Q(1-CTI)N
→ CTI = (Q- Q’) / Q / N
Q = PHA(ACTY=0)
Q : Initial charge
Q’ : Readout charge
N : Number of P transfer
PHA(Y=0) – PHA (Y=896, T)
PHA(Y=0)×896
Whole Area cal src data (8/11)
CTI =
CTI(Seg1) = CTI(Seg 2)
= [CTI(Seg0) + CTI(Seg3)] / 2
Corner cal src data
(8/15～11/20)
CTI = CTI_CONST
+ CTI_NORM×(PHAS)CTI_POW
In rev0.6…
CTI_POW = -0.5
CTI_CONST = 0 T
Q’(T) = PHA(ACTY=896, T)

13. Energy Scale Correction (Charge Trail＆CTI）
Rev0.6 Correction as a function of time, location, assuming
CTI energy dependence Ex^-0.5
CTI is constant at ACTY=0
Cyg Loop
Galactic Center Sgr C
XIS0 , XIS1, XIS2 , XIS3
XIS0 , XIS1, XIS2 , XIS3
line center energy [keV]
line center energy [keV] 1% 1%
broken line： expected energy
broken line： expected energy
ACTY
ACTY
<2% at lower energy, <1% at higher energy side.
Revised correction (rev0.7 processing) is almost ready now.

14. QE + XRT effective area verification with Crab
By S.Okada et al., XRT team
QE + XRT effective area verification with Crab

15. QE (low energy part）Calibration RXJ1856.5-3754 2005/10/24-26
Isolated NS
C-K edge ~0.3keV
Rev0.3 data -10eV offset
63.5eV blackbody
a: Based Cal on the Ground
b: a x excess0.15mmC
c: Dead Layer =Design Value
d: c x excess0.15mmC
>0.3keV 1/3-1/2 of expected value

16. E0102-72 Repeated Observation →Degradation of QE
E0102: SNR in SMC, bright in soft X-ray lines
excellent calibrator for low-E gain, QE changes
OVIII
NeIX
NeX
MgXI
OVII
model
thermal bremss + 24 Gaussian emission lines
Galactic + SMC absorption
pure C absorption from contaminant (varabs)
gain shift -5 eV ~ -15 ev
r2 ~ 1.6 (FIs) to 2.5 (BI)

17. Low background level is confirmed
→Efficient for low surface brightness

18. Night Earth BGD Spectra2 4 6 8 10
Ex (keV)

19. Cut-off Rigidity dependent BGD
Light Curve XIS1
NEP blank sky (2005/9/2)
5-10keV count rate vs COR
XIS0 XIS1 XIS2 XIS3
keV
Count rate
keV
COR
Time (s)

20. Summary 4 XIS CCD cameras are functioning properly
More than 100 targets were observed already.
Gain and energy resolution are monitored with built-in calibration source. CTI correction to compensate radiation damage induced gain decrease (~2%/year) is introduced.
Energy scale error in rev0.6 processing is 1%-2%. Rev0.7 processing with higher accuracy is now almost ready to use.
QE at high energy is almost as expected (error ~10%) from Crab data.
Low energy QE suffers significant degradation.
Possibly C-dominant material put on Optical Blocking Filter (OBF)
(Details will be presented in a separate paper)
Activity to update calibration and their tool is under going.