2. HXMT – A Chinese High Energy Astrophysics Mission Li Ti-Pei Inst. Of High Energy Physics, Chinese Academy of Sciences Center for Astrophysics, Tsinghua University

3. Hard X-ray Modulation Telescope HXMT Based on a new inversion technique – the direct demodulation method, HXMT can make both full-sky 20-250 keV hard X-ray survey with highest spatial resolution and sensitivity, and high signal-to-noise ratio pointing observation of scientific hot spot sources for temporal and spectral studies, which is planed to launch around 2010.

4. I. Imaging with Direct Demodulation

5. Integral and Swift : coded mask telescope Coded mask imager IBIT (2500 cm^2 ) Integral (2002 - ) Swift (2004 - ) Coded mask telescope BAT (5200 cm ^2 )

6. HXMT: slat collimator telescope (15 5100 cm^ 2 10-250 keV)

7. HEAO-1 A4 (1977.8 – 1979.1) 2×100cm2 1.7°×20° ～ 70 hard X-ray sources INTEGRAL (2002- ) 2500cm 2

8. Coded Mask Telescope Collimated Telescope fPdfPd fPdfPd 1 、 obs. eq. 2 、 Cross-Correlation 1 、 obs. eq. 2 、 CC transf. correlated eq. 3 、 c → f solve corelated eq. iteratively with constaints CC Inversion Direct Demodulation

9. HEAO1-A4 Cross-Correlation Direct Demodulation Map of Hard X-ray the galactic center region from HEAO1-A4 survey (from Lu et al. 1995, Proc. CHEP’95, 848) (HEAO1-A4 LED 2×100cm^2 1.7°×20°)

10. Cross-Correlation Direct Demodulation X-ray map from EXOSAT-ME slew observations (from Lu et al. 1996, Astron. Astrophys.Suppl. 115, 395) ( EXOSAT/ME 1600cm^2 0.75°)

11. RXTE / ASM ASM/RXTE data Direct demodulation map ASM/RXTE image with the direct demodulation technique (from Chen et al. 2000, Acta Astron. Sinica, 41, 214)

12. SNR (signal to noise ratio) Bad Good Angular Resolution with CC (Cross Correlation) Mid Bad with DD (Direct Demodulation) Good Best Coded Mask Collimator The DD technique makes use of information in the collected photons more sufficiently than traditional inversion technique

13.  Main Characteristics

14. Sensitivity of Swift/BAT (Markwardt et al 2005)

15. Sensitivity of HXMT

16. + imaging with 6 detectors o imaging with 12 detectors

18. Angular Resolution 12’ < 5’ 14’ Source Location (20 σ ) 0.7’ 0.6’ 0.9’ Sensitivity Pointing (10 5 s, 3σ@100keV, in mCrab) 3 0.5 4.4 Imaging (0.5year survey, in mCrab) 2 0.5 1 Integral/IBIS HXMT Swift/BAT 2002 - (~2010- ) 2004-

19. II. Scientific Goals of HXMT

20. Around 2010, HXMT will provide  more than 1000 obscured supermassive black holes and more different kinds of HX sources in our Galaxy  unique cosmic hard X-ray background imaging studies  high S/N pointing observation of scientific hot spot sources for temporal and spectral studies

21. Around 2010, HXMT will provide  more than 1000 obscured supermassive black holes and more different kinds of HX sources in our Galaxy  unique cosmic hard X-ray background imaging studies  high S/N pointing observation of scientific hot spot sources for temporal and spectral studies

23. Around 2010, HXMT will provide  more than 1000 obscured supermassive black holes and more different kinds of HX sources in our Galaxy  unique cosmic hard X-ray background imaging studies  high S/N pointing observation of scientific hot spot sources for temporal and spectral studies

24. Spectra of AGNs BeppoSAX spectrum of Seyfert II Mrk 3. Simulated HXMT spectrum of Mrk (10 5 s). The hard X-ray spectrum of Seyfert II galaxy Mrk 3 by BeppoSAX/PDS (left) and the simulated spectrum by HXMT (right, 10^5 s). Because HXMT can detect 7 times more counts, the HXMT spectrum is much better in energy band higher than 100 keV.

25. Hard X-ray emission of galaxy clusters BeppoSAX Spectrum of Coma Simulated HXMT specturm of Coma (10 5 s) Evidence for hard X-ray emission (dashed line ) from Coma cluster detected by BeppoSAX/PDS. The significance is about 4.5σ. The simulated HXMT spectrum

26. Hard X-ray emission from supernova remnants The simulated hard X-ray emission from supernova remnant Cas A by HXMT Known SNR spectra

27. HXMT is an stepping stone from INTEGRAL/IBIS and Swift/BAT to future black hole probes in NASA ’ s Beyond Einstein Program or ESA ’ s Cosmic Version

28. III. Status of HXMT mission

29. ＨＡＰＩ－４ (Inst. Of High Energy Phys., CAS)

30. HAPI-4 (IHEP, Beijing)

32. The ground test system 2000-2005 Phase A study: A project under the Major State Basic Research Program in China Founded by Ministry of Science and Technology Chinese Academy of Sciences Tsinghua University 2005.10: Phase B study

33. Partners China Academy of Space Technology Chinese Academy of Sciences Institute of High Energy Physics Academy of Opto-Electronics Center for Space Science & Applied Res. Tsinghua University

34. Possible secondary instruments Through international collaborations Soft X-ray telescope Wide field X-ray monitor Polarimeter etc HXMT/HXD 20-250keV 5100cm2 SXD SCD 1-15keV 300cm2 Si PIN 5-30keV 900cm2

35. Thank You ！ Particle Astrophysics Lab. Inst. of High Energy Physics Center for Astrophysics Tsinghua University

36.  Direct reconstruction  Direct demodulation algorithm ( Li & Wu 1993, AP&SS, 1, 1; astro-ph/0503126) iteratively solving correlation equations with constraints  Stability, convergence & global optimality Observation equations Correlation transform Correlation equations Iterative calculations Constraints DD calculations converge to a globally optimal solution

37. ○ Direct demodulation & Hopfield network Hopfield Network Continual Hopfield network with three artificial neurons Observation equations Correlation transform Correlation equations Iterative calculations Constraints State transfer equation Symmetrical condition Transfer function The DD iterations always converge on a global optimum solution

38. ○ Advantages of Direct Demodulation Resolution Sensitivity Background Generality available for any kind of observation, only if you can write out the observation equations i.e. have the data d and know all the response coefficient of the instrument to an object point i during observation to get Performing high resolution measurement with low resolution instrument Improving resolution with improving sensitivity non-linear control & chaos Depressing noises with improving sensitivity and resolution Imaging without mirror Imaging for diffuse sources

39. Simultaneously reconstruct extended and discrete features Object Direct demodulation image from scan by SCT

40. Imaging: Collimator vs Coded Mask

41. CAM SCT Object Lei F. et al., Exper. Astron. 1, 285 (1991) Li T.P & Wu M., Astrophys. Space Sci., 215,213 (1994)