M onitor of A ll-sky X -ray I mage MAXI mission on ISS

1. Zenithal view Forward view XMM-Newton Chandra RXTE software GSC fabri. & calibration SSC fabri. & calibration ASTRO-E2 Swift INTEGRAL Basic design Detailed design Fabrication and assembly MAXI operation now 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 MAXI schedule PDR 1st assembly H-IIA / HTV launch CDR Payload test Lobster-ISS Missions GLAST Monitor of All-sky X-ray ImageMAXI mission on ISS Tatehiro Mihara, Mitsuhiro Kohama, Motoki Nakajima (RIKEN), Masaru Matsuoka, Shiro Ueno, Hiroshi Tomida, Naoki Isobe, Haruyoshi Katayama, Mikio Morii (JAXA), Hiroshi Tsunemi, Emi Miyata (Osaka U), Nobuyuki Kawai, Jun Kataoka (Tokyo Tech U), Atsumasa Yoshida, Kazutaka Yamaoka (Aoyama U), Hitoshi Negoro (Nihon U) MAXI website：　http://www-maxi.tksc.jaxa.jp/ E-mail: mihara@crab.riken.jp Abstract The Monitor of All-sky X-ray Image (MAXI) is a highly sensitive all-sky monitor which will be attached to the Japanese Experiment Module of the International Space Station in 2008. MAXI utilizes scanning X-ray slit-cameras which consist of two kinds of instruments. The Gas Slit Camera (GSC) is the proportional counter with Xe and is sensitive to 2 - 30 keV. The Solid-state Slit Camera (SSC) is the CCD sensitive to 0.5 - 10 keV. The slit cameras have long field of views, and scan almost the whole sky in one orbit of ISS. As an X-ray all-sky monitor, MAXI will have an unprecedented sensitivity of 7 mCrab in one orbit scan, and 1 mCrab in one week. MAXI can monitor extragalactic objects as well as the galactic objects. MAXI will make a dynamic catalog of more than 1000 X-ray sources in time scales from hours to years. The alert of bursts and novae will be promptly informed to the world through the internet. The flight detectors were already built, and the assembling and calibration of the detectors and collimators are in progress. Long-term High-sensitivity X-ray monitoring Observational Targets 105 Spectrum in one day 104 Current sensitivity 103 Intensity[mCrab] Intensity[mCrab] Current sensitivity 102 X-ray nova ! 1orbit 101 Detection in one day 1week MAXI sensitivity 1 MAXI sensitivity Simulated MAXI observation. X-ray sources are picked up from this MAXI map and light curves for all the sources are obtained. MAXI monitors flux changes of more than 1000 X-ray sources in time scales from 96 minutes to years. MAXI takes “movies” of the X-ray sky. 0 100 200 Distance [light-yr] Time [ days ] (Tanaka et al.) Previous ASMs targeted bright galactic objects. MAXI can observe beyond our galaxy. MAXI can discover a distant X-ray nova and trace its light curve, which cannot be observed with previous ASMs. Much more bursts will be detected. A bright nova will be monitored from the rising phase to the decaying end. MAXI instruments Slit camera and Field of view Galactic coordinates International Space Station (ISS) Japanese Experiment Module (JEM) Pressurized Module Robot arm slit forward collimator Japanese Experiment Module Solid-state Slit Camera (SSC) Exposed facility Gas Slit Camera (GSC) MAXI altitude: 330 ～ 480 km inclination: 51.6 deg. orbital period: 96 minutes One-dim. detector Weight 500 kg, Size 1.8 ×1.2×0.8m X-ray from the sources goes through the slit and is detected by the one-dimensional detector. The X-ray position in the detector corresponds to the location of the source in the F.O.V. The collimatordefines the long F.O.V. Thus the source position (α,δ) is obtained. MAXI has two kinds of slit cameras: GSC and SSC. Six GSC and two SSC can cover two F.O.V.s: forward and zenithal. The F.O.V.s scan almost the whole sky with 96 minutes rotation of ISS. Gas Slit Camera (GSC) Solid-state Slit Camera (SSC) ΔE=145eV 48cm 20cm 36cm Alert and data publication Proportional counter collimator MAXI operation Low-rate data 1553B GSC utilizes gas proportional counters sensitive to 2 - 30 keV. The one-dimensional X-ray position is given by the charge division method of the carbon fiber anodes with 10μm diameter. The 12 counters makes very large 5000 cm2 area. Metorex (Oxford) manufactures large-area sealed Xe counters with space quality. Spectra obtained with SSC SSC camera and CCD SSC utilizes X-ray CCDs sensitive to 0.5 - 10 keV. One stage Peltier cooler is attached under each chip. Pixel size is 24× 24μm, and pixel number is 1024×1024. The 16 CCD × 2 cameras makes 200 cm2. Hamamatsu CCD has a deep depletion layer and a good energy resolution. Database Mid-rate data Ethernet Alert Data- base request data observers Real time contact will be established in 12～17 hours per day. The data is automatically processed in JAXA Tsukuba space center. When a burst or a nova is detected, an alert is issued within 30 s to observers in all over the world. The MAXI data goes public within 1 day. MAXI status and schedule MAXI data sheets • 2004.3. Critical Design Review (CDR) was passed. The fabrication of flight counters and parts and their calibration have started. • 2006.4. The first assembly of the whole payload. • 2008 Launch by H-IIA rocket. • ○GSC • Counters: 15 counters were already made out of 12 flight and ４ spare counters. The calibration of five of them were finished. • Collimators: Test of EM model was finished. PFM is in fabrication. • ○SSC • Cameras: Test of EM camera was finished. PFM camera is being designed and manufactured. Temperature control is being improved. • CCD chips: Fabrication and screening were finished. 48 flight chips are ready. GSC SSC Alert User