MAXI - Monitor of All-sky X-ray Image 56 th INTERNATIONAL ASTRONAUTICAL COGRESS Oct.17, 2005, Fukuoka Monitor of All-Sky X-ray Image on KIBO K. Kawasaki

Oct.17, 2005, Fukuoka

MAXI - Monitor of All-sky X-ray Image

56th INTERNATIONAL ASTRONAUTICAL COGRESS

Monitor of All-Sky X-ray Monitor of All-Sky X-ray Image on Image on KIBOKIBO

K. KawasakiK. KawasakiM. Matsuoka, S. Ueno, H. Tomida, M. Matsuoka, S. Ueno, H. Tomida,

N.Kuramata, T. Yokota, M. MoriiN.Kuramata, T. Yokota, M. MoriiJapan Arerospace Exploration Agency (JAXA)Japan Arerospace Exploration Agency (JAXA)

http://www-maxi.tksc.jaxa.jp

Oct. 17, 2005 IAC@FukuokaOct. 17, 2005 IAC@Fukuoka




Contents- MAXI overview

- MAXI Payload

- Attached payload vs. Satellite mission

- Summary

MAXI Thermal Mechanical Model




Overview of MAXI

Attached payload on Kibo-EF (Exposed Facility)All Sky X-ray Monitor on ISSScanning all sky every 90 minlaunched by H2B Rocket or Space Shuttle in 2008Mission life ~ 2years

Kibo

ISS motion

MAXI




Overview of MAXI

Two Types of X-ray Detectors (Slit Camera)Gas Slit Camera (GSC)

Solid-state Slit Camera (SSC)

Scientific GoalsLong-term AGN Variability

Diffuse X-ray Sources

GRB afterglow

X-ray Novae and Alert




FOV of MAXI

Earth

Slit camerasFOV (Vertical)

FOV (Horizontal)

Zenith

ISS moving direction

Position se

nsitive

detector

(One-dim

ension)

Scanning direction

FOV

slit




FOV of GSC & SSC







Total weight: 535 kgTotal weight: 535 kg

MAXI Payload180cm180cm

107cm107cm

80cm80cm




MAXI Payload

ATCS

ElectronicsElectronics

Grapple FixtureGrapple Fixture

PIU (PIU (KIBOKIBO-EF Interface)-EF Interface)

Carrier InterfaceCarrier Interface

Optical Star SensorOptical Star Sensor

Ring Laser GyroRing Laser Gyro

Gas Slit Cameras (GSC)Gas Slit Cameras (GSC)

Solid-state SlitSolid-state SlitCameras (SSC)Cameras (SSC)

Radiator for X-ray CCDsRadiator for X-ray CCDs




Outline of the MAXI instrument

GSC SSC

Detector

Energy Range

Effective Area

Number of camera

Field of ViewEnergy Resolution

Spatial Resolution

Proportional Counter

Xe+CO2 (1%) gas

2-30keV

5350 cm2

3+3

1.5 x 160 degree

18%1 mm

X-ray CCD

0.5-10keV

200 cm2

1+1

1.5 x 90 degree

<[email protected] mm (pixel size)




GSC (Counter,Slit & Collimators)

Slit Counter

358 mm




CCD chip PeltierCCD chip Peltier

ΔE ~ 145 eV @ 6 keV

•1024x1024 pixel CCD Osaka Univ./Hamamatsu Photonics •MAXI employs 2 SSCs•Each SSC has 16 CCD chips with one-stage Peltier cooler•Operated at –60℃•Effective area ～ 100cm2 x 2

Solid-State Slit Camera 　(SSC)

30cmCCDs

CollimatorSlit

200mm




Loop Heat Pipe Radiator System

LHP+CCD(EM) Thermal Vacuum Test

Evaporator

Condensers




Alertdelay

MAXI Performance

160 deg

1.5 deg (FWHM)

1 orbit = 90 min GSC(Gas cam)

SSC(CCD cam.)

Sky Coverage

Instant 2 % 1.3 %

1 orbit 90-98% Max 70%

Imaging PSF 1.5 deg (FWHM)

Position Accuracy < 6 arcmin

Spectroscopy([email protected])

2-30 keV

( 18 % )

0.5-10 keV

( <150 eV)

Timing Accuracy 120 sec 3-16 sec

Sensitiv-ity (5)

1 orbit 10 mCrab 20 mCrab

1 week 1 mCrab 2 mCrab

Real data

(> 50 % )

From Detection to Alert

< 30 sec (Goal)

Stored

(< 50 %)


20 min – 3 hours

User

Interf-ace

Alert Internet (mail, socket)

Data Image, Spectum, Light curve via Web browser




WeightEnvelope

535kgL1850xW800xH1065mm

KIBO-EF

PowerSurvival PowerData Coolant (ATCS) P/L Support data

120Vdc 　 350.8W(typ)120Vdc 　 96.0W(peak)

MIL-STD-1553B 　 48kbps(max)IEEE802.3/10BASE-T 600kbps(max)

FC-72 　 16 ~24℃ ℃ 　155kg/hr

ISS GN&C data 、 Solar panel joint 　　 rotation angle, etc

ELM-ES Survival Power 120Vdc ＠ JEM-EF 　116.6W(peak)

28Vdc ＠ STS 　 104W(peak)

HTV-EP Survival Power 120Vdc ＠ JEM-EF 　177.2W(peak)

50Vdc ＠ HTV 　66.3W(peak)

Resources




Interface with Kibo (Mechanical)

Grapple FixtureGrapple Fixture(I/F with Robotics arm)(I/F with Robotics arm)

PIU: Payload Interface Unit PIU: Payload Interface Unit (I/F with (I/F with KIBOKIBO-EF)-EF)

PAM-PU: Payload Attach Mechanism – Passive UnitPAM-PU: Payload Attach Mechanism – Passive Unit (Carrier Interface)(Carrier Interface)




Interface with Kibo (Electrical Power, Data communication)

Power Distributor Power Distributor

Data ProcessorData Processor Mission Data ProcessorMission Data Processor




Interface with Kibo (ATCS: Active Thermal Control System)

Cold PlatesCold Plates

AccumulatorsAccumulators




MAXI Data Communication System




Attached payload vs. Satellite Strong points:

1)MAXI utilizes ISS/Kibo’s resources so that MAXI payload design is rather simple.

- Electrical power, Coolant (ATCS)

> Neither solar panels nor radiator panels are needed.

- GN&C (Attitude and altitude control) of ISS

> Neither attitude control system nor thruster system is needed.

- Command/Telemetry system of ISS.

> MAXI ground system is rather simple.




Attached payload vs. Satellite Strong points

2) More resources (mass and volume, and man power) can be provided to the instruments.

3) ISS attitude and orbit is suitable for all-sky monitor missions.

4) On-orbit inspection by crew or TV camera. (Repair by EVA is possible, but MAXI is not designed for it.)

5) Potential capability for retrieval and upgrade on the ground. (However, MAXI will be disposed of in orbit.)




Attached payload vs. Satellite Weak points

1) Continuous communication is not feasible (50~70%). The situation will be worse until the Assembly Complete (AC).

2) We have to interface with several other systems (Kibo, ISS, carrier, and robotics), making its I/F design complicated.

3) Safety design requirements from manned space system may lead to rather a conservative design.

4) Launch schedule ambiguity.

5) Interference of FOV by the ISS structure, solar panels, and radiator panels is rather significant.




Improvement after CDR (Risk Mitigation)

1) Attitude Determination System onboard.

-To compensate data downlink missing/delay, and to alert as soon as possible.

2) LHPRS shutdown / start-up Heater are added.

-To survive at any contingency modes at assembly phase.

3) Robust launch capability

- Corresponding to the earliest launch opportunity, both HTV and Shuttle.




H-IIB Transfer Vehicle (HTV)

Launch ScheduleAugust, 2008 ?

Space ShuttleH-IIB Rocket

ELM-ES




Summary

MAXI : all-sky X-ray monitor on Kibo/ISSTwo-types of Detectors

GSCs & SSCs covering 0.5-30 keV band

2008 August ~ 2 yearsFlight Hardware is being fabricated. Some improvement has done for risk mitigation.Attached payload design is simple.Our experience was presented. Those will be beneficial to subsequent Kibo-EF missions.




- END -

http://www-maxi.tksc.jaxa.jp




GSC(Gas cam)

SSC(CCD cam.)

Sky Coverage

Instant 2 % 1.3 %

1 orbit 90-98% Max 70%

Imaging PSF 1.5 deg (FWHM)

Position Accuracy < 6 arcmin

Spectroscopy([email protected])

2-30 keV

( 18 % )

0.5-10 keV

( <150 eV)

Timing Accuracy 120 sec 3-16 sec

Sensitiv-ity (5)

1 orbit 10 mCrab 20 mCrab

1 week 1 mCrab 2 mCrab

Real data

(> 50 % )


< 30 sec (Goal)

Stored

(< 50 %)


20 min – 3 hours

User

Interf-ace

Alert Internet (mail, socket)

Data Image, Spectum, Light curve via Web browser

Alertdelay

1977-79

NASA

MAXI Performance

Systematic error level

orbit day week




Sensitivity of MAXI

1 orbit(30 sources)

1 day(100 sources)

1 week(1000 sources)




MAXI achieves the same sensitivity as this image by one month observation.




Horizontal View Zenithal View

MAXI FOV

Sky View from MAXI

Documents

MAXI - Monitor of All-sky X-ray Image 56 th INTERNATIONAL ASTRONAUTICAL COGRESS Oct.17, 2005, Fukuoka Monitor of All-Sky X-ray Image on KIBO K. Kawasaki