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New Approaches in Scintillation Detectors in the Context of

New Approaches in Scintillation Detectors in the Context of HEP Calorimetry and Medical Imaging. Paul Lecoq CERN, Geneva. X- g detection.

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New Approaches in Scintillation Detectors in the Context of

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  1. New Approaches in Scintillation Detectors in the Context of • HEP Calorimetry and Medical Imaging Paul Lecoq CERN, Geneva

  2. X-gdetection • Whatever the energy range (GeV for HEP, 100s KeV for medicalimaging)X-g detectors record only a global information on the events: • time stamp (limited by the timing resolution of the whole acquisition chain) • Total energydeposit in a crystal (100cc for HEP, 0.05 to 0.1 cc in PET) • Crystal ID for localization (limited by crystal size) • Someimprovementswith COG or DOI capability (severalcrystallayers or double readout) • 1.5mm depthresolution on 20mm long LYSO crystals for the ClearPEMwith APD readout

  3. Present limitations • As a resultthereis a trade-offbetween • Energyresolution, whichrequires the full containment of the conversion chain and therefore « large » detector blocks • Position resolution, for which the detection volume shouldberestricted to the first interaction point • This leads to a trade-offbetween • Reconstructed spatial resolution • Sensitivity (lessevents in photopeak for smaller pixels)

  4. A zoom on the conversion process (HEP) • The energy conversion from incoming X or g Rays is a complex process resulting from a cascade of events. g • Hadronicevents are even more complex • Details of the full cascade for HEP with contributions fromdifferent conversion mechanisms: scintillation and Cerenkov, wouldlead to particle identification within the shower

  5. A zoom on the conversion process (lowenergy) g

  6. A zoom on the conversion process (lowenergy) g

  7. Can we do better? Can webuild an imagingcalorimeter ? • The wholesequence carries a lot more information thanwhatisusuallyrecorded • Position of first impact • Nature of the energydeposition • Timing: the photon flux receivedfrom a « photoelectricpeak » resultsfrom ≤ 50% truephotoelectric and ≥ 50% Compton + photoelectric in the same pixel. The photons have differenttravel time. Differencecanbe as large as 150ps for the first detected photon.

  8. Towardsintellingent, multifunctionalmetamaterials • Progress towards « intelligent » materials, • metamaterialsbased on • crystallinefibers, • quantum dots, • photoniccrystals • Progress on photodetectors. Fullyintegrated and digital mutipixelimagingphotodetector • Towards a fully digital detector headwith photon counting and highaccuracy timing measurementcapability

  9. Micro-pulling-down crystal fiber growth BGO F=400mm YAG:Ce F=1mm LYSO:Ce F=2mm YAP:Ce F=2mm Courtesy Fibercryst, Lyon

  10. UV excitation Some crystal fibers YAG and LuAGup to 2m BGO ( : from 0.6 mm to 3 mm ; Length up to 30 cm) LYSO:Ce ( : from 0.6 mm to 3 mm ; Length up to 20 cm)

  11. Diffractive Optics ELT F=42m

  12. Diffractive Optics Technologies Diffractives fabrication: IC style opticallithography

  13. The calorimetry challenge Strong EW symmetry breakingdistinguish W and Z in their hadronic decays w/o kinematic constraints Possible solution: Dual Readoutscintillators Measure on an event to event basis The electromagnetic fraction in a hadronicshower By unfolding the Cerenkov contribution to the total light output ILC goal ALEPH like resolution

  14. Concept of a Meta-cable for HEP calorimetry SiPMTs SiPMTs Project funded by French ANR and CERN MOEMS diffractive optics light concentrator MOEMS diffractive optics light concentrator

  15. EndoTOFPET-USFP7-project • Development of new biomarkers • First clinicaltargets: pancreatic/prostatic cancer • Tool: dual modality PET-US endoscopic probe • Spatial resolution: 1mm • Timing resolution: 200ps • High sensitivity to detect 1mm tumor in a few mn • Energyresolution: discriminate Compton events

  16. CoincidenceSiPM-SiPM 3 February 2011

  17. Summary of results

  18. Internal probe PET head active volume 15x15x10mm3 US Probe with biopsy needle EM tracking sensor • Matrix of 18x18=324 fibers • ≤ 780mm L=10mm • Section.cylindrical or square • LYSO:Ce, LuAG:Pr,…

  19. 1 chanel of the internal probe Individual SPAD A cluster of 26x16 = 416 SPAD/fiber 10 TDC per cluster Diffractive light concentrator between fibers and SPADs

  20. Mechanicalintegration(PET head)

  21. PET matrix - 1 to 9 coupling Microlenses plate with high chromatic aberration 5 mm 5 mm 8 mm diameter sensitive spots 50 mm apart 1 mm 500mm diameter Quantum dot doped Heavy glass fibers l = variable

  22. Conclusion • Metamaterialsprovide large design flexibility • Combination of • scintillating/Cerenkovheavycrystalfibers • quantum dots in heavy host materials: fluorohafnate glasses • Fully digital SiPMwith photon countingcapability • Diffractive optics to improveopticalcouplingbetweenscintillator and photodetector offerfascinating perspectives for the design of complex and highly performant metamaterials

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