Post on 06-Jan-2016
description
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Performance of the engineering Performance of the engineering model of the MAXI/SSCmodel of the MAXI/SSC
Katayama H.a, Tomida H.a, Matsuoka M.a,
Tsunemi H.a,b, Miyata E.a,b, Kamiyama D.b, and Nemes N.b
a) Japan Aerospace Exploration Agency (JAXA)
b) Osaka Universityhttp://www-maxi.tksc.jaxa.jp
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Outline Outline
Overview of MAXI
Overview of SSC
Calibration system of SSC
Performance of the SSC-EM
Screening results of the flight CCDs
Summary and future plan
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Overview of MAXIOverview of MAXI
All Sky X-ray Monitor on ISS
Attached to JEM-EF
Scanning all sky every 90 min
launched by HIIA Transfer Vehicle in 2008
Mission life ~ 2years
JEM
ISS motion
MAXI
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Overview of MAXIOverview of MAXI
X-ray detectorsGas Slit Camera (GSC) Solid-state Slit Camera (SSC)
Attitude determination
Ring Laser Gyro (RLG)Visual Star Camera (VSC)
Thermal control system
ATCSLHPRS
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Scientific target for MAXIScientific target for MAXI
GSC (Proportional counter)Energy range : 2-30 keVE/E=18%@6keV
Aeff=5340cm2
Long-term AGN VariabilityX-ray NovaeGRB afterglow
SSC (CCD)Energy range : 0.5-10 keVE/E=2%@6keV
Aeff =200cm2
Diffuse Galactic source (line mapping at OVII, OVIII)
HEAO-1 All Sky map
ROSAT All Sky map
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Overview of SSCOverview of SSC
Slit + Slat collimator + CCDNumber of CCDs
16 CCDs X 2 Sensitivity
5.6mCrab/dayFOV
1.5x90Pointing accuracy
0.1Clocking
Parallel-summingOperation Temperature
< -60 oC (LHPRS+Peltier)
CCDs
CollimatorSlit
200mm
SSC-Z
SSC-H
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
SSC/CollimatorSSC/Collimator
FOV1.5X90 °
SlitTungsten slit Width 2.7 mm
Collimator24 thin slats
(~100m thickness,
2.4mm intervals)FOV1.5X90
Collimator
CCD
Slit
Slats of collimator(phosphorus bronze)
Tungsten slit
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
SSC/CCDSSC/CCD
FFTCCD-4673 (Hamamatsu)
Pixel size
24x24m
Number of Pixels
1024x1024
Depletion layer~70m
Coated with 2000Å Al
SSC-EM
112mm
244mm
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
SSC ElectronicsSSC Electronics
SSC Electronics (SSCE)
CCD driver / readoutPeltier control
CCD charge transfer rate = 125/62.5 kHzReadout noise < 5e- rmsEnergy resolution < 150 eV @ 5.9keV
SSCE-EM
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Calibration system of SSCCalibration system of SSC
Calibration system using fluorescent X-ray
Second targets Al, Cl, Ti, V, Fe , Ni and Zn
Cool down -20 oC with cryogenic coolerKevex
X-ray generator
Target chamber
SSC chamber
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Performance of the SSC-EM(1)Performance of the SSC-EM(1)
Energy spectrum of florescent X-rays
K, K peaks are clearly resolved Readout noise ~ 5e- Main peak + low energy tail
Spectra are fitted with double gaussian + constant
Energy scaleEnergy resolution
Al Cl Ti V
Fe
Ni
Zn
Cr
V spectrum
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Energy Scale Energy scaleLinear function
0.1% accuracy
Energy resolution
Estimated energy resolution at 0.5 keV
~ 80 eV > 60 eV (0~5e-)
Measurement of low energy response below 2 keV is needed
Performance of the SSC-EM(2)Performance of the SSC-EM(2)
Energy resolution
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Screening results of the flight Screening results of the flight CCDs (1)CCDs (1)
Screening of the flight CCDs at Osaka University (Miyata et. al 2004)
Flight candidate CCD 64
Flight CCD 32
Spare camera CCD 16
Energy resolution66 % of flight candidate CCDs show a good energy resolution below 150 eV
Kamiyama (2003)
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Screening results of the flight Screening results of the flight CCDs (2)CCDs (2)
Quantum efficiencyQuantum efficiency at 5.9 keV is more than 90 % for almost all CCDs
90 % efficiency corresponds to the depletion layer of 70 m
Hot pixels and dead columns
The number of hot pixels and dead columns is very small
70m
MAXI - Monitor of All-sky X-ray ImageMAXI - Monitor of All-sky X-ray Image
Summary and future planSummary and future plan
We have developed the engineering model of the MAXI/SSC.
We achieved the low readout noise (~5e- rms) and a good energy resolution (150 eV @ 5.9keV).
We selected 32 CCDs for flight camera and 16 CCDs for spare camera. These CCDs show a good performance.
Future plan…
Measurements of the soft X-ray response and quantum efficiency.
Fabrication of the flight camera is schedule to start in the end of 2004.