Vol. 8, 2023

Radiation Measurements


Gregor Kramberger

Pages: 106-110

DOI: 10.37392/RapProc.2023.22

With increasing number of hadron therapy centres the need for proton-CT as a powerful imaging technique is growing. Although a number of experimental p-CT has been developed there is no clinical p-CT yet. The imaging technique is based on measuring entry and exit point of the proton from the tissue as well as the residual energy of the proton. The latter is very demanding in terms of high particle rates and required resolution. The p-CT concept using novel Low Gain Avalanche Detectors (LGADs) will be described where three layers of LGAD timing detectors are used to measure the proton track and its energy. The measurement of proton energy which is vital for image reconstruction (density of electrons) is obtained from time-of-flight measurements rather than conventional scintillator-based calorimeter. The first-time resolution measurements with very thin (35 µm) LGADs and GEANT4 simulations of the p-CT performance are presented.
  1. H. Suit et al., “Proton vs carbon ion beams in the definitive radiation treatment of cancer patients,” Radiother. Oncol., vol. 95, no. 1, pp. 3 – 22, Apr. 2010.
    DOI: 10.1016/j.radonc.2010.01.015
    PMid: 20185186
  2. P. Giubilato, “Monolithic Sensors for Proton Therapy,” presented at the 10th Int. Workshop on Semiconductor Pixel Detectors for Particles and Imaging (Pixel2022), Santa Fe (NM), USA, Dec. 2022.
  3. A. M. Cormack, “Representation of a function by its line integrals with some radiological applications,” J. Appl. Phys., vol. 34, no. 9, pp. 2722 – 2727, Sep. 1963.
    DOI: 10.1063/1.1729798
  4. A. M. Koehler, “Proton radiography,” Science, vol. 160, no. 3825, pp. 303 – 304, Apr. 1968.
    DOI: 10.1126/science.160.3825.303
    PMid: 17788234
  5. K. M. Hanson et al., “The application of protons to computed tomography,” IEEE Trans. Nucl. Sci., vol. 25, no. 1, pp. 657 – 660, Feb. 1978.
    DOI: 10.1109/TNS.1978.4329389
  6. H. F. Sadrozinski et al., “Development of a head scanner for proton CT,” Nucl. Instr. Methods Phys. Res. A, vol. 699, pp. 205 – 210, Jan. 2013.
    DOI: 10.1016/j.nima.2012.04.029
    PMid: 23264711
    PMCid: PMC3524593
  7. G. Poludniowski, N. M. Allinson, P. M. Evans, “Proton Radiography and Tomography with Application to Proton Therapy,” Br. J. Radiol., vol. 88, no. 1053, 20150134, Sep. 2015.
    DOI: 10.1259/bjr.20150134
    PMid: 26043157
    PMCid: PMC4743570
  8. R. W. Schulte et al., “Conceptual design of a proton computed tomography system for applications in proton radiation therapy,” IEEE Trans. Nucl. Sci., vol. 51, no. 3, pp. 866 – 872, Jun. 2004.
    DOI: 10.1109/TNS.2004.829392
  9. G. Pellegrini et al., “Technology developments and first measurements of Low Gain Avalanche Detectors (LGAD) for high energy physics applications,” Nucl. Instr. Methods Phys. Res. A, vol. 765, pp. 12 – 16, Nov. 2014.
    DOI: 10.1016/j.nima.2014.06.008
  10. H. F-W. Sadrozinski, A. Seiden, N. Cartiglia, “4D tracking with ultra-fast silicon detectors”, ROPP, vol. 81, no. 2, 026101, Feb. 2018.
    DOI: 10.1088/1361-6633/aa94d3
  11. ATLAS Collaboration,Technical Design Report: A High-Granularity Timing Detector for the ATLAS Phase-II Upgrade, Rep. ATLAS TDR-031, CERN, Geneva, Switzerland, 2020.
    Retrieved from: https://cds.cern.ch/record/2719855
    Retrieved on: Sep. 20, 2023
  12. CMS, Collaboration,A MIP Timing Detector for the CMS Phase-2 Upgrade, Rep. CMS-TDR-020, CERN, Geneva, Switzerland, 2019.
    Retrieved from: https://cds.cern.ch/record/2667167
    Retrieved on: Sep. 20, 2023
  13. G. Kramberger, “Silicon detectors for precision track timing,” presented at the 10th Int. Workshop on Semiconductor Pixel Detectors for Particles and Imaging (Pixel2022), Santa Fe (NM), USA, Dec. 2022.
    DOI: 10.22323/1.420.0010
  14. G. Kramberger et al., “Annealing effects on operation of thin Low Gain Avalanche Detectors,” JINST, vol. 15, no. 8, P08017, Aug. 2020.
    DOI: 10.1088/1748-0221/15/08/P08017
  15. J. Debevc, “Simulation of Landau fluctuations on timing performance of LGADs,” presented at the 42nd RD50 Workshop on Radiation Hard Semiconductor Devices for Very High Luminosity Colliders, Tivat, Montenegro, Jun. 2023.
  16. S. Agostinelli et al., “Geant4—a simulation toolkit,” Nucl. Instr. Methods Phys. Res. A, vol. 506, no. 3, pp. 250 – 303, Jul. 2003.
    DOI: 10.1016/S0168-9002(03)01368-8
  17. G. Kramberger et al., “Gain dependence on free carrier concentration in LGADs,” Nucl. Instr. Methods Phys. Res. A, vol. 1046, 167669, Jan. 2023.
    DOI: 10.1016/j.nima.2022.167669
  18. G. Paternoster et al., “Trench-Isolated Low Gain Avalanche Diodes (TI-LGADs),” IEEE Electron Device Lett., vol. 41, no. 6, pp. 884 – 887, Jun. 2020.
    DOI: 10.1109/LED.2020.2991351
  19. E. Curras et al., “Inverse Low Gain Avalanche Detectors (iLGADs) for precise tracking and timing applications,” Nucl. Instr. Methods Phys. Res. A, vol. 958, 162545, Apr. 2020.
    DOI: 10.1016/j.nima.2019.162545
  20. M. Mandurrino et al., “Demonstration of 200-, 100-, and 50- μ m Pitch Resistive AC-Coupled Silicon Detectors (RSD) With 100% Fill-Factor for 4D Particle Tracking,” IEEE Electron Device Lett., vol. 40, no. 11, pp. 1780 – 1783, Nov. 2019.
    DOI: 10.1109/LED.2019.2943242
  21. L. Piccolo et al., “The first ASIC prototype of a 28 nm time-space front-end electronics for real-time tracking,” presented at theTopical Workshop on Electronics for Particle Physics (TWEPP2019), Santiago de Compostela, Spain, Sep. 2019.
    DOI: 10.22323/1.370.0022