1. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO P.Ubertini, L.Natalucci, E.M. Quadrini and collaborators IASF/INAF

2. b [deg] l [deg] INTEGRAL: coded mask FOV and source multiplicity INTEGRAL/IBIS map of Cassiopeia region (20-50 keV) mosaic 0.7-1.6 Ms, 0.4 – 12 mCrab, den Hartog et al. 2005 SPI IBIS XMM (30’) HMXB SNR AXP ms-pulsar Diffuse emission ( 26 Al, 60 Fe) from Gal plane Many different source types – outside GC and bulge !

3. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 The high energy sky is highly variable and ToO’s are important © M. Revnivtsev & E. Churazov, IKI Moscow/MPA Garching 3 deg GC region, 17-60 keV, 12 frames (36 days)

4. The transient gamma-ray sky Sources can appear in ~1000s Or a few days Or a few weeks Rev 169 Rev 171 Sguera et al., 2005 A&A, in press

5. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO CdZnTe pixellated detectors (energy band ~3-300 keV), which can be assembled in very compact, modular configuration Use of coded mask technique Very large area, high resolution instrument can be achieved by natural extension of the INTEGRAL/IBIS concept with much wider FOV to ensure detection of a large number of transient events, such as ~100/y BeppoSAX/WFC heritage

6. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO The stopping power of CdTe/CZT keV is dramatically higher than Si,Ge (45% at 200 keV, for 3mm thick detector CdTe/CZT units are also: operating at room temperature performing well in space environment (low activation, fast recovery after solar flares) small pixel manufacturing, pixel arrays mass production is relatively low cost, and established technology CdTe/CZT vs other

7. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO CZT detection plane with improved characteristics, achievable within ~ 2 years. Effort to achieve extended performance, like <0.5 keV resolution for detection of X- ray features during prompt emission of GRBs and transients. Up to 10000 cm2 can be achieved for the sensitive area if high energy range is limited to ˜ 300 keV WFGC detector Power consumption is, in average, 0.5-1 mWatt per channel; total required: ≤ 100 W for the whole unit FEE. the ISGRI MDU the ISGRI “polycell”

8. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO CZT: technology improvements Need to improve CZT performances compared to present available commercial products. The goal is to achieve a factor 5-10 better energy resolution: Improvement areas: Crystal growth and composition Surface treatment and contact depositions Front end electronics Digital processing electronics

9. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO R & D program in Italy for CZT development A program has started with a consortium of institutes/industries (P.I. M.Quadrini): IMEM-CNR for crystal development INAF Milan, Bologna, Rome and Palermo: Detector development incl. AFEE, DFEE Signal elaboration, Data Processing Instrument concept and models AAA-I-Laben for AFEE studies VENEZIA Tecnologie for evaluation of mass production Funding from ASI expected. Program already started

10. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO wide FOV (~2 sr) and moderate angular resolution (down to ~ 1-2 arcmin) to detect and localize transient events monitoring capability, but also detailed characterization of prompt emission, like GRBs, fast transients, bright source outbursts extension of the mission range from X-rays to higher energies Schematic of a possible configuration for one WFGC unit 2004 concept

11. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO We had in the first instance, considered two possible solutions, based on 2 mm and 3 mm thick CZT, respectively. The effective area for 2mm and 3mm detector thickness. Effective area The thickness of the tungsten mask will depend on the chosen CZT thickness.

12. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO a coded mask design for the WFGC could be based on MURA pattern, with 2.4 mm pitch. The mask pitch is about 1.5 times the size of the basic detector pixel. The mask is placed 1m from detector. Imaging (an exercise) the coding power is 80% the Point Source Location Accuracy, PSLA 10sigma detection. The PSLA depends on the signal-to-noise: for this configuration, is expected to be about 1.5 arcmin at the source detection limit.

13. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 Main difference from 2004 design: Limit the energy range to <300 keV (no 511) Option 1 Less area more FoV (4 detectors with smaller area) Option 2 Completely new instrument FoV structure: annular mask and detector (similar to the one of GRI-ESA Cosmic Vision Study): Area 5,000-10,000 cm2 Single annular modular detector concept Thin annular mask (0.5-1 mm W) Wide field around the X-Ray telescope for shorter slew, fast repointing, transient event always within the WFC FoV. No high energy calorimeter (4-300 keV) Plus  10-60 s on-target, lighter package, full time history for each det GRB Minus  not easy design, need R&D for detector performance electronics Others  On board SW and S/C autonomous operability, TL M resources management Possible improvement CZT Wide Field Gamma-Camera for ESTREMO

14. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO Option 1. up to 4 different units located aside on S/C support Option 2. (schematic, top view) detector modules positioned on “annulus” on a support platform, mask ~ 75 cm from detector, sensitive area 7700 cm 2 support struct S/C Mask envelope 1m 36 CZT modules

15. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO Sky coverage option 2 ~130 O Exposed area in FOV Circular FOV shape

16. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO MASS AND POWER BUDGET OPTION 1 W mask 30 kg15kg Tube/Hopper, W 70 20 CZT detection plane 40 40 Calorimeter/Veto BGO 30 30 Electronics 20 10 Structure 20 12 Harness 10 satellite Contingency 20 13 Total:240 140 x 2 units = 280 Kg Power Budget 100 W 100 W x 2 units = 200W MASS BUDGET OF VERSION 2 UNDER ESTIMATION 2004Light version

17. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO Energy range: 4-200 keV without response up to 511 Sensitive area 2300 cm2 (48 x 48 cm 2 ) Energy resolution: 1 % (E>60KeV) Sensitivity: 1 mCrab/day, 20 mCrab in 2000s (HEO E>40 keV, Solar max) PSLA: 20 arcsec Nominal ang. Resolution 10 arcmin Field of View: 90 x 90 deg @zero response (~2 ster) (> 50% coding for offset angles <35 deg) Summary of scientific performances option 1

18. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO New class of fast transients associated to HMXBs IBIS detects them very well! (Negueruela et al. 2005) IGR J17544-2619 Chandra (int’Zand et al 2005) At least up to 7 objects detected of this kind

19. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 CZT Wide Field Gamma-Camera for ESTREMO New class of fast transients associated to HMXBs XTE J1739-302 = IGR J17391-3021 IBIS/ISGRI “zooming” on source outburst (Sunyaev et al. 2003) RXTE/PCA (Smith et al 2005)

20. L.Natalucci,WHIM Conference, Roma, 17-18 Jan 2006 High localization accuracy is essential in many cases, and most important with improving sensitivity Sources in molecular cloud NGC6334, as seen by Chandra ISGRI error box Hard X-ray source identified as a background AGN (Bassani et al., astroph/0510338) CZT Wide Field Gamma-Camera for ESTREMO