Japanese High Energy Astrophysics Mission on ISSJapanese High Energy Astrophysics Mission on ISS

Monitor of All-Sky X-ray Image Monitor of All-Sky X-ray Image (MAXI)(MAXI)

N. Kawai N. Kawai 河合誠之河合誠之 , J. Kataoka , J. Kataoka (( 東京工業大学：東京工業大学： Tokyo Institute of Technology)Tokyo Institute of Technology)M. Matsuoka, S. Ueno, H. Tomida, (NASDA)M. Matsuoka, S. Ueno, H. Tomida, (NASDA)

H. Tsunemi, E. Miyata (Osaka Univ.)H. Tsunemi, E. Miyata (Osaka Univ.)T. Mihara, H. Negoro, M. Kohama, I. Sakurai (RIKEN)T. Mihara, H. Negoro, M. Kohama, I. Sakurai (RIKEN)

A. Yoshida (Aoyama Univ.), Y. Shirasaki, (NAOJ),A. Yoshida (Aoyama Univ.), Y. Shirasaki, (NAOJ),

Overview

• All Sky X-ray Monitor on ISS– Scanning all sky every 90 min

• Two Types of X-ray Detectors– Gas Slit Camera (GSC)– Solid-state Slit Camera (SSC)

• Mission 2005 August ~ 2+ years• Scientific Goals

– Long-term AGN Variability– X-ray Novae– Diffuse X-ray Sources– GRB afterglow

• International Space Station (ISS)

• Japanese Experiment Module (JEM)

JEM

MAXI

ISS & JEM

Grapple Fixture for a robot armGrapple Fixture for a robot arm

ElectronicsElectronics

Gas Slit Cameras (GSC)Gas Slit Cameras (GSC): X-ray gas proportional counter: X-ray gas proportional counter

Solid-state SlitSolid-state SlitCameras (SSC)Cameras (SSC): X-ray CCD: X-ray CCD

Optical Star SensorOptical Star Sensor

Radiator for X-ray CCDsRadiator for X-ray CCDs

180cm180cm

80cm80cm

100cm100cm

Total weight: 490 kgTotal weight: 490 kg

Overview of MAXI

ATCS

FOV of MAXI

Point Spread Functionincident angle = 0 deg in latitude direction

incident angle = 20 degin latitude direction

Gas Slit Camera(GSC)

Test Counter

358 mm

• 1-D position sensitive counter (anodes : 10 m carbon fiber)

• MAXI employs 12 counters (total area = 5340cm2)

• (1.5x80 deg) x 3 =>1.5x160 deg

• 2-30keV range • position resolution ～ 1mm

Position resolution and linearity over the 30 cm sensitive area of GSC

ΔE ~ 145 eV @ 6 keV

Hamamatsu Photonics CCD

•MAXI employs 2 SSCs

•Each SSC has 16 CCD chips developed by Hamamatsu Photonics

•Effective area ～ 100cm2 x 2

Solid-State Slit Camera(SSC)

　　　　　 Time (days after outburst)

Flu

x

(Cra

b u

nit

)

0.5-30 keV X-ray spectrum available every day!

Detectable in one day

Detectable in one week

One Crab

One mCrab

X-ray Nova Light Curves and MAXI Sensitivity

Detectable in one week

100

10

1

0.1

0.01

0.001

0 50 100 150 200 250

Sensitivity of MAXI

1 orbit(30 sources)

1 day(100 sources)

1 week(1000 sources)

RXTE ASM

Simulation of MAXI Observation

One Orbit 5-month

ISS-JEM MAXI

Ethernet

3 Mbps, 5 hr/day

NASDA

DRTS

Command

Data

NASA Alart data Stored data

MAXI Science team

MAXI Data Communication System

Mil 1553B

30-50 kbps, 24 hr/day

MAXI/GSC: X1608-52simulation

MAXI/GSC: MCG -6-30-15simulation

MAXI/GSC: Ark 564simulation

?

?

MAXI Schedule

1997 1999 2001 2003 20059 10 11 12 13 14 15 16 17 18 19

採択 開発確認審査 PDR/SR-1 CDR/SR-2 SR-3 打上 運用NASA/SR1 NASA/SR2 NASA/SR3

概念設計 基本設計 詳細設計 設計維持

部分試作 部分試験 TMM試験 FM製作 各部試験 総合試験

EM一部の 射場試験

PFM物品の調達

wait ?

H

Now under TMM test!

Selection Kickoff R Launch

Summary

• MAXI : all-sky X-ray monitor on JEM/ISS– the first all-sky X-ray monitor for AGNs

• Two-types of Detectors– GSCs & SSCs covering 0.5-30 keV band

• Detection-limit down to 1-2 mCrab for 1 day• 2005 August ~ 2 years