1. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Mosaic Detector: Experiments for Therapy and Space Research R.Pleskac GSI / Biophysics

2. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Overview Hadrontherapy & Space Research  Significance of nuclear fragmentation  Cave A measurements (Bragg curves, nuclear fragmentation, microdosimetry, beam widening)  FIRST experiment (double-differential cross-section for Z particles) Mosaic Detector  Requirements  Design  Time Line

3. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Significance of nuclear fragmentation in RT with light ions Carbon ion therapy 100-400 MeV/u I. Pshenichnov High-energy carbon beam stopping in water Nuclear fragmentation  Loss of primary ions  depth-dose, RBE Total reaction cross section 1-2 b  Buildup of secondary fragments  dose-tail, lateral dose Exp. Investigations (physical characterization) –LBL Berkeley Ne 670 MeV/u 1970’s W. Schimmerling –NIRS/HIMAC Chiba C, light ions 1990’s T. Kanai –GSI Biophysics C, light ions 1990’s

4. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Before treatment Definition and delineation of target volume (CT,MRI,PET) transform patient CT-data to water-equivalent path length of ions Treatment planning: - find best entrance ports - optimization (absorbed dose [Gy]) physical model - biological optim. (RBE (LET(Z,E),dose …) [GyE]) Verify dose distribution in water phantom (tolerable deviation < 5%) Patient positioning Patient treatment Bragg curves + fragmentation data fragmentation data

5. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Mechanical accuracy: 1 μm for relative thickness 0.1 mm absolute Precision Bragg curve measurements Comparison of absolute B.P. positions measured at GSI and HIT synchrotrons at the same nominal beam energies: → agreement within < 2 ‰ rel. deviation The present data base includes precise B.P. position data for p, 3 He, 7 Li, 12 C, 16 O

6. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Bragg curves of C water Bragg curves of 12 C water peak-width and height are affected by –straggling –fragmentation increasing tail dose © D.Schardt

7. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Microdosimetry in-phantom measurements Tissue-equivalent proportional chamber (TEPC) Sensitive volume 120 mb TE-gas

8. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Beam Widening – - Film Stack in Water Acquarium Photo© G.Martino Irradiated GaF Chromic films Stack of films placed in the water- phantom aligned with the beam axis

9. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Fragmentation studies - Fragment buildup in thick targets - Neutrons - Microdosimetry

10. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Fragmentation Setup Angular distribution setup → Beam energy of 120 MeV/u → Cylindrical water target (diameter of 150 mm) → Telescope positionned at 0°, 20°, 30°, 60°, 90° and 120° The ΔE–E telescope detector Loss of primary ions setup → beam energy of 300 MeV/u → Target: 0, 1, …, 7 large water flasks → Telescope positionned at 0°

11. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Signal processing & Data Acquisition (DAQ) system Number of primary ions N0 → big ionization chamber Number of fragments N → ΔE-E telescope Trigger → START and/or BaF 2 detector DAQ → GSI Multi Branch System (MBS) → Aug 2007 – CAMAC CVC based DAQ → Feb 2009 – CAMAC GTBC based DAQ → Aug 2012 – VME based DAQ RAW DATA → List Mode Data (LMD) files DATA ANALYSIS → on event-by-event basis → ROOT program (online / offline) → ΔE-E scatter plot → "banana" cuts → identification of fragments

12. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Identification of Fragments 7 Li at 120 MeV/u: ΔE-E scatter plot p d t 3He 4He γ+n ΔE (plastic) E (BaF2)

13. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Loss of primary ions and fragment buildup Loss of carbon Ions by nuclear reactions E. Haettner et al., GSI 2005 Buildup of secondary fragments Surviving fraction

14. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Spectral data E. Haettner et al., GSI 2005 Buildup of secondary fragments Fragment energy spectra 4mm behind B.P. E 0 12 C He energy spectra at angles 0° - 6° E 0 12 C Comparison with PHITS-code

15. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 FIRST – experimental setup in cave C IR – START scintillator IR – Beam Monitor IR – Target IR – Si Pixel Vertex Detector IR- KENTROS ALADIN Magnet TP-MUSIC IV TOF wall LAND → Beam diagnostics → New detectors in interaction region (IR) → ALADIN dipole → MUSIC + ToF Wall → LAND Measurable → Double-differential cross-section for Z particles Experiment in August 2011 (carbon beam fragmented on thick targets) → C + C (5 mm) at 400 MeV/u → C + Au (0.5 mm) at 400 MeV/u → coincidence measurement → on event-by-event basis

16. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Future Experiments at GSI: Irradiation facilities Cave B (rear part) Preparation of FIRST E = 0.1 – 2 GeV/u Medical cave Cave A Fragmentation Experiments Space research E < 15 MeV/u Cave C FIRST experiment

17. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Mosaic Detector new GSI mosaic detector (based on n_ToF design) n_ToF mosaic detector

18. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Requirements / Geometry Purpose:  Beam monitor (counter) + START/STOP for ToF + Energy loss  Particles: protons – carbon – iron - HI  Intensities: 1e0 – 1e8/sec (replacing existing START plastic scintillator) sCVD:  4,5 x 4,5 mm2 x 300 μm  active area 4,0 x 4,0 mm2 (~ 80 % of total area) Mosaic detector:  3 x 3 sCVD  total area 13,5 x 13,5 mm2 (beam spot 5 – 10 mm FWHM)  9 x C2 + 1 x C6 preamplifiers

19. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Characteristics Signals  protons - oxygen at 500 MeV: → 3.2 – 350 fC  3.2 fC / 4 ns = 0.8 μA → 0.8 μA * 50 Ω = 40 μV  40 dB current amplifier (f = 100) → 40 μV * 100 = 4 mV  protons: S/B = 4 mV / 2.5 mV = 1.6  oxygen: S/B = 200 mV / 3.2 mV = 62.5  protons: using quick charge amplifier (4 mV/fC) → 3.2 fC * 4 mV/fC = 12.8 mV → S/B = 12.8 mV / 0.6 mV (noice) = 21.3 Time Resolution  case of 16O: 1 ns / 100 ps = 10 ps  case of protons: 3.5 ns / 21.3 ns = 150 ps

20. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Proton / Carbon Interaction Ionization for protons at 200 – 500 MeV Ionization for carbon at 1 – 10 GeV → 150 – 600 fC (150 – 600 MIP)

21. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 n_ToF PCB Design (1)

22. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 n_ToF PCB Design (2) Top layerBottom layer Readout lines

23. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 Time line  January 2013 – assembling  February 2013 – final testing  End of February 2013 - delivering

24. 1st ADAMAS Workshop, GSI, 2012R.Pleskac18/12/2012 THANK YOU FOR YOUR ATTENTION !