TY - JOUR

T1 - A High-Granularity Digital Tracking Calorimeter Optimized for Proton CT

AU - Alme, Johan

AU - Barnaföldi, Gergely Gábor

AU - Barthel, Rene

AU - Borshchov, Vyacheslav

AU - Bodova, Tea

AU - van den Brink, Anthony

AU - Brons, Stephan

AU - Chaar, Mamdouh

AU - Eikeland, Viljar

AU - Feofilov, Grigory

AU - Genov, Georgi

AU - Grimstad, Silje

AU - Grøttvik, Ola

AU - Helstrup, Håvard

AU - Herland, Alf

AU - Hilde, Annar Eivindplass

AU - Igolkin, Sergey

AU - Keidel, Ralf

AU - Kobdaj, Chinorat

AU - van der Kolk, Naomi

AU - Listratenko, Oleksandr

AU - Malik, Qasim Waheed

AU - Mehendale, Shruti

AU - Meric, Ilker

AU - Nesbø, Simon Voigt

AU - Odland, Odd Harald

AU - Papp, Gábor

AU - Peitzmann, Thomas

AU - Seime Pettersen, Helge Egil

AU - Piersimoni, Pierluigi

AU - Protsenko, Maksym

AU - Rehman, Attiq Ur

AU - Richter, Matthias

AU - Röhrich, Dieter

AU - Samnøy, Andreas Tefre

AU - Seco, Joao

AU - Setterdahl, Lena

AU - Shafiee, Hesam

AU - Skjolddal, Øistein Jelmert

AU - Solheim, Emilie

AU - Songmoolnak, Arnon

AU - Sudár, Ákos

AU - Sølie, Jarle Rambo

AU - Tambave, Ganesh

AU - Tymchuk, Ihor

AU - Ullaland, Kjetil

AU - Underdal, Håkon Andreas

AU - Varga-Köfaragó, Monika

AU - Volz, Lennart

AU - Wagner, Boris

AU - Widerøe, Fredrik Mekki

AU - Xiao, Ren Zheng

AU - Yang, Shiming

AU - Yokoyama, Hiroki

AU - Феофилов, Григорий Александрович

N1 - Publisher Copyright: © Copyright © 2020 Alme, Barnaföldi, Barthel, Borshchov, Bodova, van den Brink, Brons, Chaar, Eikeland, Genov, Grimstad, Grøttvik, Helstrup, Herland, Hilde, Keidel, Kobdaj, van der Kolk, Listratenko, Malik, Mehendale, Meric, Nesbø, Odland, Papp, Peitzmann, Pettersen, Piersimoni, Protsenko, Rehman, Richter, Röhrich, Samnøy, Seco, Setterdahl, Shafiee, Skjolddal, Solheim, Songmoolnak, Sudár, Sølie, Tambave, Tymchuk, Ullaland, Underdal, Varga-Köfaragó, Volz, Wagner, Weigold, Widerøe, Xiao, Yang and Yokoyama.

PY - 2020/10/22

Y1 - 2020/10/22

N2 - A typical proton CT (pCT) detector comprises a tracking system, used to measure the proton position before and after the imaged object, and an energy/range detector to measure the residual proton range after crossing the object. The Bergen pCT collaboration was established to design and build a prototype pCT scanner with a high granularity digital tracking calorimeter used as both tracking and energy/range detector. In this work the conceptual design and the layout of the mechanical and electronics implementation, along with Monte Carlo simulations of the new pCT system are reported. The digital tracking calorimeter is a multilayer structure with a lateral aperture of 27 cm × 16.6 cm, made of 41 detector/absorber sandwich layers (calorimeter), with aluminum (3.5 mm) used both as absorber and carrier, and two additional layers used as tracking system (rear trackers) positioned downstream of the imaged object; no tracking upstream the object is included. The rear tracker’s structure only differs from the calorimeter layers for the carrier made of ∼200 μm carbon fleece and carbon paper (carbon-epoxy sandwich), to minimize scattering. Each sensitive layer consists of 108 ALICE pixel detector (ALPIDE) chip sensors (developed for ALICE, CERN) bonded on a polyimide flex and subsequently bonded to a larger flexible printed circuit board. Beam tests tailored to the pCT operation have been performed using high-energetic (50–220 MeV/u) proton and ion beams at the Heidelberg Ion-Beam Therapy Center (HIT) in Germany. These tests proved the ALPIDE response independent of occupancy and proportional to the particle energy deposition, making the distinction of different ion tracks possible. The read-out electronics is able to handle enough data to acquire a single 2D image in few seconds making the system fast enough to be used in a clinical environment. For the reconstructed images in the modeled Monte Carlo simulation, the water equivalent path length error is lower than 2 mm, and the relative stopping power accuracy is better than 0.4%. Thanks to its ability to detect different types of radiation and its specific design, the pCT scanner can be employed for additional online applications during the treatment, such as in-situ proton range verification.

AB - A typical proton CT (pCT) detector comprises a tracking system, used to measure the proton position before and after the imaged object, and an energy/range detector to measure the residual proton range after crossing the object. The Bergen pCT collaboration was established to design and build a prototype pCT scanner with a high granularity digital tracking calorimeter used as both tracking and energy/range detector. In this work the conceptual design and the layout of the mechanical and electronics implementation, along with Monte Carlo simulations of the new pCT system are reported. The digital tracking calorimeter is a multilayer structure with a lateral aperture of 27 cm × 16.6 cm, made of 41 detector/absorber sandwich layers (calorimeter), with aluminum (3.5 mm) used both as absorber and carrier, and two additional layers used as tracking system (rear trackers) positioned downstream of the imaged object; no tracking upstream the object is included. The rear tracker’s structure only differs from the calorimeter layers for the carrier made of ∼200 μm carbon fleece and carbon paper (carbon-epoxy sandwich), to minimize scattering. Each sensitive layer consists of 108 ALICE pixel detector (ALPIDE) chip sensors (developed for ALICE, CERN) bonded on a polyimide flex and subsequently bonded to a larger flexible printed circuit board. Beam tests tailored to the pCT operation have been performed using high-energetic (50–220 MeV/u) proton and ion beams at the Heidelberg Ion-Beam Therapy Center (HIT) in Germany. These tests proved the ALPIDE response independent of occupancy and proportional to the particle energy deposition, making the distinction of different ion tracks possible. The read-out electronics is able to handle enough data to acquire a single 2D image in few seconds making the system fast enough to be used in a clinical environment. For the reconstructed images in the modeled Monte Carlo simulation, the water equivalent path length error is lower than 2 mm, and the relative stopping power accuracy is better than 0.4%. Thanks to its ability to detect different types of radiation and its specific design, the pCT scanner can be employed for additional online applications during the treatment, such as in-situ proton range verification.

KW - ALICE pixel detector (ALPIDE)

KW - Complementary Metal Oxide Semiconductor (CMOS)

KW - hadrontherapy

KW - Monte Carlo

KW - proton CT

UR - http://www.scopus.com/inward/record.url?scp=85095697844&partnerID=8YFLogxK

U2 - 10.3389/fphy.2020.568243

DO - 10.3389/fphy.2020.568243

M3 - Article

AN - SCOPUS:85095697844

VL - 8

JO - Frontiers in Physics

JF - Frontiers in Physics

SN - 2296-424X

M1 - 568243

ER -