2. The Hard X-ray Modulation Telescope (HXMT) Fangjun Lu (Institute of High Energy Physics, Chinese Academy of Sciences) On behalf of the HXMT group

3. Low Energy X-ray Telescope (LE) (SCD, 1-15KeV,300 cm 2 ) Medium Energy X-ray Telescope (ME) (SiPIN, 5-30keV,1000 cm 2 ) Payloads of HXMT High Energy X-ray Telescope (HE) （ 18 modules, 20-250keV,5000 cm 2 ）

4. HE NaI(Tl)/CsI(Na) Phoswich –Total Detect Area ~5000 cm 2 –Energy Range 20 ～ 250 keV –Energy Resolution ~16% (@60keV) –Continuum Sensitivity ~3.0×10 -7 ph cm -2 s -1 keV -1,or 0.5 mCrab (3σ@100keV,10 5 s) –Field of View 5.7°x 5.7° –Source Location ≤1 arcmin (20  ) –Angular Resolution ≤5 arcmin (20  ) ME 5-30 keV, SiPIN, 1000 cm 2 (we are optimizing the design of HXMT and may will double the detecting area of ME) LE 1-15 keV, SCD, 300 cm 2 Mass ~2700 kg (payload ~1100 kg) Dimension 2.0×2.0×2.8 m 3 (L×W×H) Nominal Mission lifetime 3 years Orbit Altitude 550km ， Inclination 43° Attitude Three-axis stabilized Control precision ： ±0.25° Stability: 0.005 °/s Measurement accuracy: <0.01° Characteristics of the HXMT Mission

5. Current Status of the HXMT Mission –Proposed in 1993 –973 Major State Basic Research Project in China since April 2000 (Pre- Phase A study) Total about $5M All the key technical problems for the HE telescope solved. –Main participating institutions: Chinese Academy of Sciences Tsinghua University Chinese Academy of Space Technology –PI and Co-PI: Ti-Pei Li and Shuang-Nan Zhang –Selected last year as the first Chinese space astronomy mission for launch around 2010 Full mission cost about $80M –We just passed a technical review on this Wednesday, and HXMT is scheduled to enter pre-flight phase (Phase B) next October.

6. Configuration of the high energy X-ray telescope Active Shield Collimator Phoswich detector PMT Structures

7. Each module has a field of view (FOV) of 5.7º×1.1º and the long axes of two neighboring FOVs differ by 10º. Collimator Shielding Ring Detector

8. The Main Detector system of the HXMT X-ray photons

9. The ground testing system

10. The imaging performance of the HXMT Source Location < 1 arcmin Angular resolution < 5 arcmin 20 sigma source

11. Sensitivity

12. Angular Resolution 12’ 5’ 14’ Source Location (20σ) 1’ 1’ 1’ Pointed Sensitivity (mCrab@100 keV, 10 5 s) 3.8 0.5 9 ½ Year Survey Sensitivity (mCrab,20-250keV) 2 0.5 1 Observation Capability All sky survey ok good yes Selected sky deep survey good good bad Narrow field pointing observation bad good no Integral/IBIS HXMT/HE Swift/BAT

13. Low energy X-ray telescope (2 modules, 300 cm 2 ) Collimator ： fabricated with Electro- deposition or from plates. FOV of 1°x 6°and 1°x 3°, Thickness: 5cm. Material can be Gold-plated copper. Detector: SCD （ Swept Charge Device ） developed by e2v. Energy range: 1 － 15 keV ， Time resolution :1ms ， Spectral resolution: 450eV@5.9keV Working temperature ： -30 － 0 ℃ Main Scientific Objectives ： （ 1 ） Extending the energy coverage to low energy （ 2 ） Multi-wavelength X-ray variability （ 3 ） Absorption column density to AGNs

14. Medium Energy x-ray telescope (ME) (2 modules, 1000 cm 2 ) Collimator: similar to that of LE and defines FOV of 1°×6 °. Detector ： covers 5 － 30keV, using SiPIN or thin CdZnTe Main Scientific objectives ： （ 1 ） Cosmic X-ray background; （ 2 ） Absorption materials surrounding AGNs; （ 3 ） Temporal variability in medium energy X-ray.

15. Continuum Sensitivity of ME 0.1 mCrab@10 keV

16. A Possible Fourth Telescope –ASI of Italy contributes a pair of X-ray focusing telescopes plus X-ray polarimeter (XRT+XPOL) for HXMT. –People involved: Enrico Costa, Fabio Muleri, Paolo Soffitta, Ronaldo Bellazzini Alessandro Brez, Gloria Spandre, Vincenzo Cotroneo, Giovanni Pareschi

17. From the modulation curve it is derived the polarization degree and angle of the X-ray source. Bellazzini et al. 2006

18. Interface Electronics Control Electr

20. Current design Sensitive Area of the telescope

22. Minimum Detectable Polarization

24. Observation modes Survey –All sky scan mode –3-axis stabilized anti-earth oriented: roll angle=0º, region span=-43º-43º, 66 days roll angle=30º, region span=-13º-73º, 66 days roll angle=-30º, region span=-73º-13º, 66 days Deep scanning observation of selected sky regions Pointed observations

25. HXMT Sky Survey Observations The three-phase sky survey of HXMT. In phase (a) the roll angle is β=0°, and the scanned declination range is δ=-43° － 43°, in phase (b) β=30° and δ=-13° － 73°, and in phase (c) β=-30°, δ=-73° － 13°. (d) illustrates the total exposure after the three- phase scan survey.

26. HXMT is capable of conducting a deep full sky survey in half a year with a sensitivity of 0.5 mCrab (20-250 keV), and more than 1,000 hard X-ray sources will be detected. The sensitivity around 10 keV is about 0.1 mCrab with ME. Background fluctuations, all within 3.15 σSignificance distribution of a 0.5 mCrab source, 60% are higher than 3.15σ Monte-Carlo simulations of the sensitivity of HXMT (for point sources) in a half-year all-sky survey

27. Simulated HXMT capability on Galactic diffuse hard X-ray emission. Model ： Strong et al A&A 411, L447(2003), Fig.2 HXMT simulation

28. On going hard X-ray survey projects The US satellite SWIFT can do hard X-ray all-sky survey. Its survey sensitivity is dominated by systematic errors. For regions in the Galactic Plane (l 45°(1/3 sky), the limiting sensitivity will be ~0.6 mCrab. The final SWIFT hard X-ray catalogue may will contain 200 extragalactic hard X-ray sources (Barthelmy et al. astroph/0507410). Two years of INTEGRAL/IBIS observation has reached ~1 mCrab for regions with the deepest exposures and 209 sources (in which ~50 are active galactic nuclei) have been catalogued.

29. The real survey program may will be changed according to how deep the final SWIFT/BAT and INTEGRAL/IBIS survey will be. If they reach a sensitivity of 0.5 mCrab for most of the sky, we may will carry out for example an one-year survey for half sky to improve the sensitivity.

30. Small region scan Deep scan of interesting regions to reach high sensitivity (such as the lockmann hole region and the Galactic Center region. Theoretically, an one- month’s observation of a region with a radius of 10º can reach a sensitivity limit of 0.1mCrab. Periodically scan of the Galactic bulge to study the variations of the Galactic hard X-ray sources.

31. Pointed Observations Study the X-ray variability at multi-wavelength (1- 250 keV) of the X-ray binary systems: QPOs, relations between the hard and soft X-ray components. Study the broad band X-ray spectrum of bright AGNs, X-ray binaries, bright SNRs, pulsars, and bright clusters of galaxies.

32. BeppoSAX Spectrum of Coma Simulated HXMT specturm of Coma (10 5 s) BeppoSAX spectrum of Coma －－ 4.5σ detection of non-thermal X-ray emission. Simulated HXMT spectrum of Coma －－ much better constraints on the non-thermal component.

33. Simulated HXMT spectrum of Cas A. Current SNR X-ray specturm. Only up to 30 keV

34. Hard X-ray sky survey with highest sensitivity High precision multi-wavelength X-ray full sky map: diffuse background and cosmic variance Discover highly obscured supermassive BHs and study the obscuring materials: galaxy formation and evolution Discover new types of high energy objects: usual surprises of new surveys Diffuse hard X-ray emission in the Galaxy. Main advantages and key science of HXMT

35. Main advantages and key science of HXMT (II) High precision pointed observations of high energy objects Space-time in strong gravitational field: dynamics and radiation near BH horizons of stellar mass and supermassive BHs Equation of state in strong magnetic field: neutron star and its surface properties High energy particle acceleration: AGN, SNR, shock and relativistic jets Large scale structure: through hard X-ray detection of galaxy clusters

36. Beyond Einstein Program HXMT

37. Orbit and Operation

38. Constraints on Orbit Design Operation mode: survey mode requires inclination angle not less than 25° (sky coverage) and precession speed of the orbital plane not exceeds 0.3 ° /orbit ( ~1/3 of FOV 1.1 ° ) Low background level: lower inclination angle Reduce the passage of SAA belt and other radiation belt Ground station ： Beijing Station only Launch station: Xichang, Taiyuan, Jiuquan Nominal Lifetime: 3 yrs (height > 500km)

39. Final orbit parameters Low Earth Orbit Height: 550km Inclination angle: 43~45° Period: ~96min.

40. HXMT schedule 200 7

41. Con-X XEUS HXMT See further (earlier) and clearer See inner Evolution of the whole universe Survey the local universe

42. Thanks!