Mapping the Sensitive Volume of an Ion-Counting Nanodosimeter

We present two methods of independently mapping the dimensions of the sensitive volume in an ion-counting nanodosimeter. The first method is based on a calculational approach simulating the extraction of ions from the sensitive volume, and the second method on probing the sensitive volume with 250 MeV protons. Sensitive-volume maps obtained with both methods are compared and systematic errors inherent in both methods are quantified.Comment: 27 pages, 8 figures. Submitted to JINST, Jan. 16 200

Proton radiography and tomography with application to proton therapy

Proton radiography and tomography have long promised benefit for proton therapy. Their first suggestion was in the early 1960s and the first published proton radiographs and CT images appeared in the late 1960s and 1970s, respectively. More than just providing anatomical images, proton transmission imaging provides the potential for the more accurate estimation of stopping-power ratio (SPR) inside a patient and hence improved treatment planning and verification. With the recent explosion in growth of clinical proton therapy facilities, the time is perhaps ripe for the imaging modality to come to the fore. Yet many technical challenges remain to be solved before proton CT scanners become commonplace in the clinic. Research and development in this field is currently more active that at any time with several prototype designs emerging. This review introduces the principles of proton radiography and tomography, its historical developments, the raft of modern prototype systems and the primary design issues

A Single-Particle Trigger for Time-of-Flight Measurements in Prompt-Gamma Imaging

[EN] Tracking of single particles accelerated by synchrotrons is a subject that crosses several physics fields. The high clinical intensities used in particle therapy that can exceed 10(9)p/s make this task very challenging. The tracking of the arrival time of single particles in the ion beam is fundamental for the verification of the particle range and dose delivered to the patient. We present a prototype made of scintillating fibers which has been used to provide time-of-flight (TOF) information for three beam species currently accelerated at the Heidelberg Ion-Beam Therapy Center (HIT). We have demonstrated a time-tracker for a prompt-gamma spectroscopy system that allows for a background TOF rejection with a sub-nanosecond time resolution.PM was supported by a research fellowship for postdoctoral researchers from the Alexander von Humboldt Foundation, Bonn, Germany. RD was supported by the International Max Planck Research School for Quantum Dynamics in Physics, Chemistry and Biology, Heidelberg, Germany.Martins, PM.; Dal Bello, R.; Seimetz, M.; Hermann, G.; Kihm, T.; Seco, J. (2020). A Single-Particle Trigger for Time-of-Flight Measurements in Prompt-Gamma Imaging. Frontiers in Physics. 8:1-13. https://doi.org/10.3389/fphy.2020.00169S1138Parodi, K., Crespo, P., Eickhoff, H., Haberer, T., Pawelke, J., Schardt, D., & Enghardt, W. (2005). Random coincidences during in-beam PET measurements at microbunched therapeutic ion beams. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 545(1-2), 446-458. doi:10.1016/j.nima.2005.02.002Crespo, P., Barthel, T., Frais-Kolbl, H., Griesmayer, E., Heidel, K., Parodi, K., … Enghardt, W. (2005). Suppression of random coincidences during in-beam PET measurements at ion beam radiotherapy facilities. IEEE Transactions on Nuclear Science, 52(4), 980-987. doi:10.1109/tns.2005.852637Testa, E., Bajard, M., Chevallier, M., Dauvergne, D., Le Foulher, F., Freud, N., … Testa, M. (2008). Monitoring the Bragg peak location of 73MeV∕u carbon ions by means of prompt γ-ray measurements. Applied Physics Letters, 93(9), 093506. doi:10.1063/1.2975841Biegun, A. K., Seravalli, E., Lopes, P. C., Rinaldi, I., Pinto, M., Oxley, D. C., … Schaart, D. R. (2012). Time-of-flight neutron rejection to improve prompt gamma imaging for proton range verification: a simulation study. Physics in Medicine and Biology, 57(20), 6429-6444. doi:10.1088/0031-9155/57/20/6429Smeets, J., Roellinghoff, F., Prieels, D., Stichelbaut, F., Benilov, A., Busca, P., … Dubus, A. (2012). Prompt gamma imaging with a slit camera for real-time range control in proton therapy. Physics in Medicine and Biology, 57(11), 3371-3405. doi:10.1088/0031-9155/57/11/3371Verburg, J. M., Riley, K., Bortfeld, T., & Seco, J. (2013). Energy- and time-resolved detection of prompt gamma-rays for proton range verification. Physics in Medicine and Biology, 58(20), L37-L49. doi:10.1088/0031-9155/58/20/l37Golnik, C., Hueso-González, F., Müller, A., Dendooven, P., Enghardt, W., Fiedler, F., … Pausch, G. (2014). Range assessment in particle therapy based on promptγ-ray timing measurements. Physics in Medicine and Biology, 59(18), 5399-5422. doi:10.1088/0031-9155/59/18/5399Cambraia Lopes, P., Clementel, E., Crespo, P., Henrotin, S., Huizenga, J., Janssens, G., … Schaart, D. R. (2015). Time-resolved imaging of prompt-gamma rays for proton range verification using a knife-edge slit camera based on digital photon counters. Physics in Medicine and Biology, 60(15), 6063-6085. doi:10.1088/0031-9155/60/15/6063Petzoldt, J., Roemer, K. E., Enghardt, W., Fiedler, F., Golnik, C., Hueso-González, F., … Pausch, G. (2016). Characterization of the microbunch time structure of proton pencil beams at a clinical treatment facility. Physics in Medicine and Biology, 61(6), 2432-2456. doi:10.1088/0031-9155/61/6/2432Verburg, J. M., & Seco, J. (2014). Proton range verification through prompt gamma-ray spectroscopy. Physics in Medicine and Biology, 59(23), 7089-7106. doi:10.1088/0031-9155/59/23/7089Hueso-González, F., Enghardt, W., Fiedler, F., Golnik, C., Janssens, G., Petzoldt, J., … Pausch, G. (2015). First test of the prompt gamma ray timing method with heterogeneous targets at a clinical proton therapy facility. Physics in Medicine and Biology, 60(16), 6247-6272. doi:10.1088/0031-9155/60/16/6247Martins, P. M., Dal Bello, R., Rinscheid, A., Roemer, K., Werner, T., Enghardt, W., … Seco, J. (2017). Prompt gamma spectroscopy for range control with CeBr3. Current Directions in Biomedical Engineering, 3(2), 113-117. doi:10.1515/cdbme-2017-0023Gil, E. C., Albarrán, E. M., Minucci, E., Nüssle, G., Padolski, S., Petrov, P., … Kozhuharov, V. (2017). The beam and detector of the NA62 experiment at CERN. Journal of Instrumentation, 12(05), P05025-P05025. doi:10.1088/1748-0221/12/05/p05025Schüttauf, A. (2004). Timing RPCs in FOPI. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 533(1-2), 65-68. doi:10.1016/j.nima.2004.07.002Alici, A. (2012). Status and performance of the ALICE MRPC-based Time-Of-Flight detector. Journal of Instrumentation, 7(10), P10024-P10024. doi:10.1088/1748-0221/7/10/p10024Blanco, A., Fonte, P., Garzon, J. A., Koenig, W., Kornakov, G., & Lopes, L. (2013). Performance of the HADES-TOF RPC wall in a Au + Au beam at 1.25 AGeV. Journal of Instrumentation, 8(01), P01004-P01004. doi:10.1088/1748-0221/8/01/p01004Sadrozinski, H. F.-W., Ely, S., Fadeyev, V., Galloway, Z., Ngo, J., Parker, C., … Vinattieri, A. (2013). Ultra-fast silicon detectors. 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S., Mackie, T. R., & Attix, F. H. (1992). Water-equivalent plastic scintillation detectors for high-energy beam dosimetry: II. Properties and measurements. Physics in Medicine and Biology, 37(10), 1901-1913. doi:10.1088/0031-9155/37/10/007Beaulieu, L., & Beddar, S. (2016). Review of plastic and liquid scintillation dosimetry for photon, electron, and proton therapy. Physics in Medicine and Biology, 61(20), R305-R343. doi:10.1088/0031-9155/61/20/r305Beddar, S., & Beaulieu, L. (Eds.). (2016). Scintillation Dosimetry. Imaging in Medical Diagnosis and Therapy. doi:10.1201/b19491Marcatili, S., Collot, J., Curtoni, S., Dauvergne, D., Hostachy, J.-Y., Koumeir, C., … Yamouni, M. (2020). Ultra-fast prompt gamma detection in single proton counting regime for range monitoring in particle therapy. Physics in Medicine & Biology, 65(24), 245033. doi:10.1088/1361-6560/ab7a6cKirn, T. (2017). SciFi – A large scintillating fibre tracker for LHCb. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 845, 481-485. doi:10.1016/j.nima.2016.06.057Leverington, B. D., Dziewiecki, M., Renner, L., & Runze, R. (2018). A prototype scintillating fibre beam profile monitor for Ion Therapy beams. Journal of Instrumentation, 13(05), P05030-P05030. doi:10.1088/1748-0221/13/05/p05030Vignati, A., Monaco, V., Attili, A., Cartiglia, N., Donetti, M., Mazinani, M. F., … Cirio, R. (2017). Innovative thin silicon detectors for monitoring of therapeutic proton beams: preliminary beam tests. Journal of Instrumentation, 12(12), C12056-C12056. doi:10.1088/1748-0221/12/12/c12056Krimmer, J., Dauvergne, D., Létang, J. M., & Testa, É. (2018). Prompt-gamma monitoring in hadrontherapy: A review. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 878, 58-73. doi:10.1016/j.nima.2017.07.063Pausch, G., Berthold, J., Enghardt, W., Römer, K., Straessner, A., Wagner, A., … Kögler, T. (2020). Detection systems for range monitoring in proton therapy: Needs and challenges. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 954, 161227. doi:10.1016/j.nima.2018.09.062Hueso-Gonzalez, F., & Bortfeld, T. (2020). Compact Method for Proton Range Verification Based on Coaxial Prompt Gamma-Ray Monitoring: A Theoretical Study. IEEE Transactions on Radiation and Plasma Medical Sciences, 4(2), 170-183. doi:10.1109/trpms.2019.2930362Haberer, T., Debus, J., Eickhoff, H., Jäkel, O., Schulz-Ertner, D., & Weber, U. (2004). The heidelberg ion therapy center. Radiotherapy and Oncology, 73, S186-S190. doi:10.1016/s0167-8140(04)80046-xHara, K., Hata, K., Kim, S., Mishina, M., Sano, M., Seiya, Y., … Yasuoka, K. (1998). Radiation hardness and mechanical durability of Kuraray optical fibers. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 411(1), 31-40. doi:10.1016/s0168-9002(98)00281-2Joram, C., Haefeli, G., & Leverington, B. (2015). Scintillating Fibre Tracking at High Luminosity Colliders. Journal of Instrumentation, 10(08), C08005-C08005. doi:10.1088/1748-0221/10/08/c08005EkelhofRJ Studies for the LHCb SciFi Tracker - Development of Modules from Scintillating Fibres and Tests of their Radiation Hardness2016Online control of particle therapy - CLaRyS collaboration1825 DauvergneD Final MediNet Network Meeting2019Tessonnier, T., Mairani, A., Chen, W., Sala, P., Cerutti, F., Ferrari, A., … Parodi, K. (2018). Proton and helium ion radiotherapy for meningioma tumors: a Monte Carlo-based treatment planning comparison. Radiation Oncology, 13(1). doi:10.1186/s13014-017-0944-3Mein, S., Dokic, I., Klein, C., Tessonnier, T., Böhlen, T. T., Magro, G., … Mairani, A. (2019). Biophysical modeling and experimental validation of relative biological effectiveness (RBE) for 4He ion beam therapy. Radiation Oncology, 14(1). doi:10.1186/s13014-019-1295-zSchoemers, C., Feldmeier, E., Naumann, J., Panse, R., Peters, A., & Haberer, T. (2015). The intensity feedback system at Heidelberg Ion-Beam Therapy Centre. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 795, 92-99. doi:10.1016/j.nima.2015.05.054Werner, F., Bauer, C., Bernhard, S., Capasso, M., Diebold, S., Eisenkolb, F., … Zietara, K. (2017). Performance verification of the FlashCam prototype camera for the Cherenkov Telescope Array. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 876, 31-34. doi:10.1016/j.nima.2016.12.056Actis, M., Agnetta, G., Aharonian, F., Akhperjanian, A., Aleksić, J., … Antico, F. (2011). Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy. Experimental Astronomy, 32(3), 193-316. doi:10.1007/s10686-011-9247-0Dal Bello, R., Magalhaes Martins, P., Graça, J., Hermann, G., Kihm, T., & Seco, J. (2019). Results from the experimental evaluation of CeBr scintillators for He prompt gamma spectroscopy. Medical Physics, 46(8), 3615-3626. doi:10.1002/mp.13594Puehlhofer, G., Bauer, C., Bernhard, S., Capasso, M., Diebold, S., Eisenkolb, F., … Zietara, K. (2016). FlashCam: a fully-digital camera for the medium-sized telescopes of the Cherenkov Telescope Array. Proceedings of The 34th International Cosmic Ray Conference — PoS(ICRC2015). doi:10.22323/1.236.1039Testa, M., Bajard, M., Chevallier, M., Dauvergne, D., Freud, N., Henriquet, P., … Testa, E. (2010). Real-time monitoring of the Bragg-peak position in ion therapy by means of single photon detection. Radiation and Environmental Biophysics, 49(3), 337-343. doi:10.1007/s00411-010-0276-2Dal Bello, R., Magalhaes Martins, P., Brons, S., Hermann, G., Kihm, T., Seimetz, M., & Seco, J. (2020). Prompt gamma spectroscopy for absolute range verification of 12C ions at synchrotron-based facilities. Physics in Medicine & Biology, 65(9), 095010. doi:10.1088/1361-6560/ab797321768 LeoWR Techniques for Nuclear and Particle Physics Experiments: A How-to Approach1994Graeff, C., Weber, U., Schuy, C., Saito, N., Volz, L., Piersimoni, P., … Kraemer, M. (2018). [OA027] Helium as a range probe in carbon ion therapy. Physica Medica, 52, 11. doi:10.1016/j.ejmp.2018.06.099Mazzucconi, D., Agosteo, S., Ferrarini, M., Fontana, L., Lante, V., Pullia, M., & Savazzi, S. (2018). Mixed particle beam for simultaneous treatment and online range verification in carbon ion therapy: Proof‐of‐concept study. Medical Physics, 45(11), 5234-5243. doi:10.1002/mp.13219Scintillating Fiber Trackers: recent developments and applications204 BlancF 14th ICATPP Conference on Astroparticle, Particle, Space Physics and Detectors for Physics Applications2013JoramC UwerU LeveringtonBD KirnT BachmannS EkelhofRJ LHCb Scintillating Fibre Tracker Engineering Design Review Report: Fibres, Mats and Modules201

A Monte-Carlo-based study of a single-2D-detector proton-radiography system

PURPOSE: To assess the feasibility of a proton radiography (pRG) system based on a single thin pixelated detector for water-equivalent path length (WEPL) and relative stopping power (RSP) measurements.METHODS: A model of a pRG system consisting of a single pixelated detector measuring energy deposition and proton fluence was investigated in a Geant4-based Monte Carlo study. At the position directly after an object traversed by a broad proton beam, spatial 2D distributions are calculated of the energy deposition in, and the number of protons entering the detector. Their ratio relates to the 2D distribution of the average stopping power of protons in the detector. The system response is calibrated against the residual range in water of the protons to provide the 2D distribution of the WEPL of the object. The WEPL distribution is converted into the distribution of the RSP of the object. Simulations have been done, where the system has been tested on 13 samples of homogeneous materials of which the RSPs have been calculated and compared with RSPs determined from simulations of residual-range-in-water, which we refer to as reference RSPs.RESULTS: For both human-tissue- and non-human-tissue-equivalent materials, the RSPs derived with the detector agree with the reference values within 1%.CONCLUSION: The study shows that a pRG system based on one thin pixelated detection screen has the potential to provide RSP predictions with an accuracy of 1%.</p

Can megavoltage computed tomography reduce proton range uncertainties in treatment plans for patients with large metal implants?

Treatment planning calculations for proton therapy require an accurate knowledge of radiological path length, or range, to the distal edge of the target volume. In most cases, the range may be calculated with sufficient accuracy using kilovoltage (kV) computed tomography (CT) images. However, metal implants such as hip prostheses can cause severe streak artifacts that lead to large uncertainties in proton range. The purposes of this study were to quantify streak-related range errors and to determine if they could be avoided by using artifact-free megavoltage (MV) CT images in treatment planning. Proton treatment plans were prepared for a rigid, heterogeneous phantom and for a prostate cancer patient with a metal hip prosthesis using corrected and uncorrected kVCT images alone, uncorrected MVCT images and a combination of registered MVCT and kVCT images (the hybrid approach). Streak-induced range errors of 5-12 mm were present in the uncorrected kVCT-based patient plan. Correcting the streaks by manually assigning estimated true Hounsfield units improved the range accuracy. In a rigid heterogeneous phantom, the implant-related range uncertainty was estimated at approach, the kVCT images provided good delineation of soft tissues due to high-contrast resolution, and the streak-free MVCT images provided smaller range uncertainties because they did not require artifact correction. © 2008 Institute of Physics and Engineering in Medicine

Gamma and proton irradiation effects and thermal stability of electrical characteristics of metal-oxide-silicon capacitors with atomic layer deposited Al<inf>2</inf>O<inf>3</inf> dielectric

The radiation hardness and thermal stability of the electrical characteristics of atomic layer deposited Al2O3 layers to be used as passivation films for silicon radiation detectors with slim edges are investigated. To directly measure the interface charge and to evaluate its change with the ionizing dose, metal-oxide-silicon (MOS) capacitors implementing differently processed Al2O3 layers were fabricated on p-type silicon substrates. Qualitatively similar results are obtained for degradation of capacitance-voltage and current-voltage characteristics under gamma and proton irradiations up to equivalent doses of 30 Mrad and 21.07 Mrad, respectively. While similar negative charge densities are initially extracted for all non-irradiated capacitors, superior radiation hardness is obtained for MOS structures with alumina layers grown with H2O instead of O3 as oxidant precursor. Competing effects between radiation-induced positive charge trapping and hydrogen release from the H2O-grown Al2O3 layers may explain their higher radiation resistance. Finally, irradiated and non-irradiated MOS capacitors with differently processed Al2O3 layers have been subjected to thermal treatments in air at temperatures ranging between 100 °C and 200 °C and the thermal stability of their electrical characteristics has been evaluated. Partial recovery of the gamma-induced degradation has been noticed for O3-grown MOS structures. This can be explained by a trapped holes emission process, for which an activation energy of 1.38 ± 0.15 eV has been extracted.Peer reviewe

Experimental comparison of photon versus particle computed tomography to predict tissue relative stopping powers

Purpose: Measurements comparing relative stopping power (RSP) accuracy of state-of-the-art systems representing single-energy and dual-energy computed tomography (SECT/DECT) with proton CT (pCT) and helium CT (HeCT) in biological tissue samples. Methods: We used 16 porcine and bovine samples of various tissue types and water, covering an RSP range from 0.90urn:x-wiley:00942405:media:mp15283:mp15283-math-00010.06 to 1.78 urn:x-wiley:00942405:media:mp15283:mp15283-math-00020.05. Samples were packed and sealed into 3D-printed cylinders (urn:x-wiley:00942405:media:mp15283:mp15283-math-0003 cm, urn:x-wiley:00942405:media:mp15283:mp15283-math-0004 cm) and inserted into an in-house designed cylindrical polymethyl methacrylate (PMMA) phantom (urn:x-wiley:00942405:media:mp15283:mp15283-math-0005 cm, urn:x-wiley:00942405:media:mp15283:mp15283-math-0006 cm). We scanned the phantom in a commercial SECT and DECT (120 kV; 100 and 140 kV/Sn (tin-filtered)); and acquired pCT and HeCT (urn:x-wiley:00942405:media:mp15283:mp15283-math-0007 MeV/u, 2urn:x-wiley:00942405:media:mp15283:mp15283-math-0008 steps, urn:x-wiley:00942405:media:mp15283:mp15283-math-0009 (p)/urn:x-wiley:00942405:media:mp15283:mp15283-math-0010 (He) particles/projection) with a particle imaging prototype. RSP maps were calculated from SECT/DECT using stoichiometric methods and from pCT/HeCT using the DROP-TVS algorithm. We estimated the average RSP of each tissue per modality in cylindrical volumes of interest and compared it to ground truth RSP taken from peak-detection measurements. Results: Throughout all samples, we observe the following root-mean-squared RSP prediction errors urn:x-wiley:00942405:media:mp15283:mp15283-math-0011 combined uncertainty from reference measurement and imaging: SECT 3.10urn:x-wiley:00942405:media:mp15283:mp15283-math-00122.88%, DECT 0.75urn:x-wiley:00942405:media:mp15283:mp15283-math-00132.80%, pCT 1.19urn:x-wiley:00942405:media:mp15283:mp15283-math-0014 2.81%, and HeCT 0.78urn:x-wiley:00942405:media:mp15283:mp15283-math-00152.81%. The largest mean errors urn:x-wiley:00942405:media:mp15283:mp15283-math-0016 combined uncertainty per modality are SECT 8.22 urn:x-wiley:00942405:media:mp15283:mp15283-math-00172.79% in cortical bone, DECT 1.74urn:x-wiley:00942405:media:mp15283:mp15283-math-00182.00% in back fat, pCT 1.80 urn:x-wiley:00942405:media:mp15283:mp15283-math-00194.27% in bone marrow, and HeCT 1.37urn:x-wiley:00942405:media:mp15283:mp15283-math-00204.25% in bone marrow. Ring artifacts were observed in both pCT and HeCT reconstructions, imposing a systematic shift to predicted RSPs. Conclusion: Comparing state-of-the-art SECT/DECT technology and a pCT/HeCT prototype, DECT provided the most accurate RSP prediction, closely followed by particle imaging. The novel modalities pCT and HeCT have the potential to further improve on RSP accuracies with work focusing on the origin and correction of ring artifacts. Future work will study accuracy of proton treatment plans using RSP maps from investigated imaging modalities

Calibration method and performance of a time-of-flight detector to measure absolute beam energy in proton therapy

Background: The beam energy is one of the most significant parameters in particle therapy since it is directly correlated to the particles' penetration depth inside the patient. Nowadays, the range accuracy is guaranteed by offline routine quality control checks mainly performed with water phantoms, 2D detectors with PMMA wedges, or multi-layer ionization chambers. The latter feature low sensitivity, slow collection time, and response dependent on external parameters, which represent limiting factors for the quality controls of beams delivered with fast energy switching modalities, as foreseen in future treatments. In this context, a device based on solid-state detectors technology, able to perform a direct and absolute beam energy measurement, is proposed as a viable alternative for quality assurance measurements and beam commissioning, paving the way for online range monitoring and treatment verification. Purpose: This work follows the proof of concept of an energy monitoring system for clinical proton beams, based on Ultra Fast Silicon Detectors (featuring tenths of ps time resolution in 50&nbsp;μm active thickness, and single particle detection capability) and time-of-flight techniques. An upgrade of such a system is presented here, together with the description of a dedicated self-calibration method, proving that this second prototype is able to assess the mean particles energy of a monoenergetic beam without any constraint on the beam temporal structure, neither any a priori knowledge of the beam energy for the calibration of the system. Methods: A new detector geometry, consisting of sensors segmented in strips, has been designed and implemented in order to enhance the statistics of coincident protons, thus improving the accuracy of the measured time differences. The prototype was tested on the cyclotron proton beam of the Trento Protontherapy Center (TPC). In addition, a dedicated self-calibration method, exploiting the measurement of monoenergetic beams crossing the two telescope sensors for different flight distances, was introduced to remove the systematic uncertainties independently from any external reference. Results: The novel calibration strategy was applied to the experimental data collected at TPC (Trento) and CNAO (Pavia). Deviations between measured and reference beam energies in the order of a few hundreds of keV with a maximum uncertainty of 0.5 MeV were found, in compliance with the clinically required water range accuracy of 1&nbsp;mm. Conclusions: The presented version of the telescope system, minimally perturbative of the beam, relies on a few seconds of acquisition time to achieve the required clinical accuracy and therefore represents a feasible solution for beam commission, quality assurance checks, and online beam energy monitoring

Search for heavy resonances decaying into a Z or W boson and a Higgs boson in final states with leptons and b-jets in 139 fb-1 of pp collisions at sqrt(s) = 13 TeV with the ATLAS detector

This article presents a search for new resonances decaying into a Z or W boson and a 125 GeV Higgs boson h, and it targets the νν¯¯¯bb¯¯, ℓ+ℓ−bb¯¯, or ℓ±νbb¯¯ final states, where ℓ = e or μ, in proton-proton collisions at sqrt(s) = 13 TeV. The data used correspond to a total integrated luminosity of 139 fb−1 collected by the ATLAS detector during Run 2 of the LHC at CERN. The search is conducted by examining the reconstructed invariant or transverse mass distributions of Zh or Wh candidates for evidence of a localised excess in the mass range from 220 GeV to 5 TeV. No significant excess is observed and 95% confidence-level upper limits between 1.3 pb and 0.3 fb are placed on the production cross section times branching fraction of neutral and charged spin-1 resonances and CP-odd scalar bosons. These limits are converted into constraints on the parameter space of the Heavy Vector Triplet model and the two-Higgs-doublet model