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J Seco - One of the best experts on this subject based on the ideXlab platform.
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prompt Gamma Spectroscopy for absolute range verification of 12c ions at synchrotron based facilities
Physics in Medicine and Biology, 2020Co-Authors: Riccardo Dal Bello, Paulo Magalhaes Martins, S Brons, G Hermann, T Kihm, M Seimetz, J SecoAbstract:The physical range uncertainty limits the exploitation of the full potential of charged particle therapy. In this work, we face this issue aiming to measure the absolute Bragg peak position in the target. We investigate p, 4He, 12C and 16O beams accelerated at the Heidelberg Ion-Beam Therapy Center. The residual range of the primary 12C ions is correlated to the energy spectrum of the prompt Gamma radiation. The prompt Gamma Spectroscopy method was demonstrated for proton beams accelerated by cyclotrons and is developed here for the first time for heavier ions accelerated by a synchrotron. We develop a detector system that includes (i) a spectroscopic unit based on cerium(III) bromide and bismuth germanium oxide scintillating crystals, (ii) a beam trigger based on an array of scintillating fibers and (iii) a data acquisition system based on a FlashADC. We test the system in two different scenarios. In the first series of experiments, we detect and identify 19 independent spectral lines over a wide Gamma energy spectrum in the presence of the four ion species for different targets, including a water target with a titanium insert. In the second series of experiments, we introduce a collimator aiming to relate the spectral information to the range of the primary particles. We perform extensive measurements for a 12C beam and demonstrate submillimetric precision for the measurement of its Bragg peak position in the experimental setup. The features of the energy and time spectra for Gamma radiation induced by p, 4He and 16O are investigated upstream and downstream from the Bragg peak position. We conclude the analysis by extrapolating the required future developments, which would be needed to achieve range verification with a 2 mm accuracy during a single fraction delivery of [Formula: see text] physical dose.
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results from the experimental evaluation of cebr scintillators for he prompt Gamma Spectroscopy
Medical Physics, 2019Co-Authors: Riccardo Dal Bello, Paulo Magalhaes Martins, G Hermann, T Kihm, J Seco, Joao GracaAbstract:Purpose The presence of range uncertainties hinders the exploitation of the full potential of charged particle therapy. Several range verification techniques have been proposed to mitigate this limitation. Prompt Gamma Spectroscopy (PGS) is among the most promising solutions for online and in vivo range verification. In this work, we present the experimental results of the detection of prompt Gamma radiation, induced by 4 He beams at the Heidelberg Ion-Beam Therapy Center (HIT). The results were obtained, using a spectroscopic unit of which the design has been optimized using Monte Carlo simulations. Methods The spectroscopic unit is composed by a primary cerium bromide (CeBr 3 ) crystal surrounded by a secondary bismuth germanate (BGO) crystal for anticoincidence detection (AC). The digitalization of the signals is performed with an advanced FADC/FPGA system. The 4 He beams at clinical energies and intensities are delivered to multiple targets in the experimental cave at the HIT. We analyze the production of prompt Gamma on oxygen and carbon targets, as well as high Z materials such as titanium and aluminum. The quantitative analysis includes a systematic comparison of the signal-to-noise ratio (SNR) improvement for the spectral lines when introducing the AC detection. Moreover, the SNR improvement could provide a reduction of the number of events required to draw robust conclusions. We perform a statistic analysis to determine the magnitude of such an effect. Results We present the energy spectra detected by the primary CeBr 3 and the secondary BGO. The combination of these two detectors leads to an average increase of the signal-to-noise ratio by a factor 2.1, which confirms the Monte Carlo predictions. The spectroscopic unit is capable of detecting efficiently the discrete Gamma emission over the full energy spectrum. We identify and analyze 19 independent spectral lines in an energy range spacing from E γ = 0.718 MeV to E γ = 6.13 MeV. Moreover, when introducing the AC detection, the number of events required to determine robustly the intensity of the discrete lines decreases. Finally, the analysis of the low-energy reaction lines determines whether a thin metal insert is introduced in the beam direction. Conclusions This work provides the experimental characterization of the Spectroscopy unit in development for range verification through PGS at the HIT. Excellent performances have been demonstrated over the full prompt Gamma energy spectrum with 4 He beams at clinical energies and intensities.
Riccardo Dal Bello - One of the best experts on this subject based on the ideXlab platform.
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prompt Gamma Spectroscopy for absolute range verification of 12c ions at synchrotron based facilities
Physics in Medicine and Biology, 2020Co-Authors: Riccardo Dal Bello, Paulo Magalhaes Martins, S Brons, G Hermann, T Kihm, M Seimetz, J SecoAbstract:The physical range uncertainty limits the exploitation of the full potential of charged particle therapy. In this work, we face this issue aiming to measure the absolute Bragg peak position in the target. We investigate p, 4He, 12C and 16O beams accelerated at the Heidelberg Ion-Beam Therapy Center. The residual range of the primary 12C ions is correlated to the energy spectrum of the prompt Gamma radiation. The prompt Gamma Spectroscopy method was demonstrated for proton beams accelerated by cyclotrons and is developed here for the first time for heavier ions accelerated by a synchrotron. We develop a detector system that includes (i) a spectroscopic unit based on cerium(III) bromide and bismuth germanium oxide scintillating crystals, (ii) a beam trigger based on an array of scintillating fibers and (iii) a data acquisition system based on a FlashADC. We test the system in two different scenarios. In the first series of experiments, we detect and identify 19 independent spectral lines over a wide Gamma energy spectrum in the presence of the four ion species for different targets, including a water target with a titanium insert. In the second series of experiments, we introduce a collimator aiming to relate the spectral information to the range of the primary particles. We perform extensive measurements for a 12C beam and demonstrate submillimetric precision for the measurement of its Bragg peak position in the experimental setup. The features of the energy and time spectra for Gamma radiation induced by p, 4He and 16O are investigated upstream and downstream from the Bragg peak position. We conclude the analysis by extrapolating the required future developments, which would be needed to achieve range verification with a 2 mm accuracy during a single fraction delivery of [Formula: see text] physical dose.
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results from the experimental evaluation of cebr scintillators for he prompt Gamma Spectroscopy
Medical Physics, 2019Co-Authors: Riccardo Dal Bello, Paulo Magalhaes Martins, G Hermann, T Kihm, J Seco, Joao GracaAbstract:Purpose The presence of range uncertainties hinders the exploitation of the full potential of charged particle therapy. Several range verification techniques have been proposed to mitigate this limitation. Prompt Gamma Spectroscopy (PGS) is among the most promising solutions for online and in vivo range verification. In this work, we present the experimental results of the detection of prompt Gamma radiation, induced by 4 He beams at the Heidelberg Ion-Beam Therapy Center (HIT). The results were obtained, using a spectroscopic unit of which the design has been optimized using Monte Carlo simulations. Methods The spectroscopic unit is composed by a primary cerium bromide (CeBr 3 ) crystal surrounded by a secondary bismuth germanate (BGO) crystal for anticoincidence detection (AC). The digitalization of the signals is performed with an advanced FADC/FPGA system. The 4 He beams at clinical energies and intensities are delivered to multiple targets in the experimental cave at the HIT. We analyze the production of prompt Gamma on oxygen and carbon targets, as well as high Z materials such as titanium and aluminum. The quantitative analysis includes a systematic comparison of the signal-to-noise ratio (SNR) improvement for the spectral lines when introducing the AC detection. Moreover, the SNR improvement could provide a reduction of the number of events required to draw robust conclusions. We perform a statistic analysis to determine the magnitude of such an effect. Results We present the energy spectra detected by the primary CeBr 3 and the secondary BGO. The combination of these two detectors leads to an average increase of the signal-to-noise ratio by a factor 2.1, which confirms the Monte Carlo predictions. The spectroscopic unit is capable of detecting efficiently the discrete Gamma emission over the full energy spectrum. We identify and analyze 19 independent spectral lines in an energy range spacing from E γ = 0.718 MeV to E γ = 6.13 MeV. Moreover, when introducing the AC detection, the number of events required to determine robustly the intensity of the discrete lines decreases. Finally, the analysis of the low-energy reaction lines determines whether a thin metal insert is introduced in the beam direction. Conclusions This work provides the experimental characterization of the Spectroscopy unit in development for range verification through PGS at the HIT. Excellent performances have been demonstrated over the full prompt Gamma energy spectrum with 4 He beams at clinical energies and intensities.
R Grzywacz - One of the best experts on this subject based on the ideXlab platform.
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β delayed neutron emission from ga 85
Physical Review C, 2018Co-Authors: K Miernik, K P Rykaczewski, R Grzywacz, C J Gross, M Madurga, David H Miller, D W Stracener, J C BatchelderAbstract:Decay of $^{85}\mathrm{Ga}$ was studied by means of $\ensuremath{\beta}$-neutron-$\ensuremath{\Gamma}$ Spectroscopy. A pure beam of $^{85}\mathrm{Ga}$ was produced at the Holifield Radioactive Ion Beam Facility using a resonance ionization laser ion source and a high-resolution electromagnetic separator. The $\ensuremath{\beta}$-delayed neutron emission probability was measured for the first time, yielding 70(5)%. An upper limit of 0.1% for $\ensuremath{\beta}$-delayed two-neutron emission was also experimentally established for the first time. A detailed decay scheme including absolute $\ensuremath{\Gamma}$-ray intensities was obtained. Results are compared with theoretical $\ensuremath{\beta}$-delayed emission models.
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large β delayed one and two neutron emission rates in the decay of ga 86
Physical Review Letters, 2013Co-Authors: K P Rykaczewski, K Miernik, R Grzywacz, C J Gross, M Madurga, J C Batchelder, D Miller, I N BorzovAbstract:Beta decay of $^{86}\mathrm{Ga}$ was studied by means of $\ensuremath{\beta}$-neutron-$\ensuremath{\Gamma}$ Spectroscopy. An isotopically pure $^{86}\mathrm{Ga}$ beam was produced at the Holifield Radioactive Ion Beam Facility using a resonance ionization laser ion source and high-resolution electromagnetic separation. The decay of $^{86}\mathrm{Ga}$ revealed a half-life of ${43}_{\ensuremath{-}15}^{+21}\text{ }\text{ }\mathrm{ms}$ and large $\ensuremath{\beta}$-delayed one-neutron and two-neutron branching ratios of ${P}_{1n}=60(10)%$ and ${P}_{2n}=20(10)%$. The $\ensuremath{\beta}\ensuremath{\Gamma}$ decay of $^{86}\mathrm{Ga}$ populated a 527 keV transition that is interpreted as the deexcitation of the first ${2}^{+}$ state in the $N=54$ isotone $^{86}\mathrm{Ge}$ and suggests a quick onset of deformation in Ge isotopes beyond $N=50$.
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large β delayed one and two neutron emission rates in the decay of 86ga
Physical Review Letters, 2013Co-Authors: K P Rykaczewski, K Miernik, R Grzywacz, C J Gross, M Madurga, David H Miller, J C Batchelder, I N BorzovAbstract:Beta decay of $^{86}\mathrm{Ga}$ was studied by means of $\ensuremath{\beta}$-neutron-$\ensuremath{\Gamma}$ Spectroscopy. An isotopically pure $^{86}\mathrm{Ga}$ beam was produced at the Holifield Radioactive Ion Beam Facility using a resonance ionization laser ion source and high-resolution electromagnetic separation. The decay of $^{86}\mathrm{Ga}$ revealed a half-life of ${43}_{\ensuremath{-}15}^{+21}\text{ }\text{ }\mathrm{ms}$ and large $\ensuremath{\beta}$-delayed one-neutron and two-neutron branching ratios of ${P}_{1n}=60(10)%$ and ${P}_{2n}=20(10)%$. The $\ensuremath{\beta}\ensuremath{\Gamma}$ decay of $^{86}\mathrm{Ga}$ populated a 527 keV transition that is interpreted as the deexcitation of the first ${2}^{+}$ state in the $N=54$ isotone $^{86}\mathrm{Ge}$ and suggests a quick onset of deformation in Ge isotopes beyond $N=50$.
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large beta delayed neutron emission probabilities in the 78ni region
Physical Review Letters, 2009Co-Authors: J A Winger, K P Rykaczewski, R Grzywacz, C J Gross, J C Batchelder, S Ilyushkin, C Goodin, J H Hamilton, A KorgulAbstract:The $\ensuremath{\beta}$-delayed neutron branching ratios (${P}_{\ensuremath{\beta}n}$) for nuclei near doubly magic $^{78}\mathrm{Ni}$ have been directly measured using a new method combining high-resolution mass separation, reacceleration, and digital $\ensuremath{\beta}\mathrm{\text{\ensuremath{-}}}\ensuremath{\Gamma}$ Spectroscopy of $^{238}\mathrm{U}$ fission products. The ${P}_{\ensuremath{\beta}n}$ values for the very neutron-rich isotopes $^{76--78}\mathrm{Cu}$ and $^{83}\mathrm{Ga}$ were found to be much higher than previously reported and predicted. Revised calculations of the $\ensuremath{\beta}n$ process, accounting for new mass measurements and an inversion of the $\ensuremath{\pi}2{p}_{3/2}$ and $\ensuremath{\pi}1{f}_{5/2}$ orbitals, are in better agreement with these new experimental results.
K Miernik - One of the best experts on this subject based on the ideXlab platform.
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β delayed neutron emission from ga 85
Physical Review C, 2018Co-Authors: K Miernik, K P Rykaczewski, R Grzywacz, C J Gross, M Madurga, David H Miller, D W Stracener, J C BatchelderAbstract:Decay of $^{85}\mathrm{Ga}$ was studied by means of $\ensuremath{\beta}$-neutron-$\ensuremath{\Gamma}$ Spectroscopy. A pure beam of $^{85}\mathrm{Ga}$ was produced at the Holifield Radioactive Ion Beam Facility using a resonance ionization laser ion source and a high-resolution electromagnetic separator. The $\ensuremath{\beta}$-delayed neutron emission probability was measured for the first time, yielding 70(5)%. An upper limit of 0.1% for $\ensuremath{\beta}$-delayed two-neutron emission was also experimentally established for the first time. A detailed decay scheme including absolute $\ensuremath{\Gamma}$-ray intensities was obtained. Results are compared with theoretical $\ensuremath{\beta}$-delayed emission models.
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large β delayed one and two neutron emission rates in the decay of ga 86
Physical Review Letters, 2013Co-Authors: K P Rykaczewski, K Miernik, R Grzywacz, C J Gross, M Madurga, J C Batchelder, D Miller, I N BorzovAbstract:Beta decay of $^{86}\mathrm{Ga}$ was studied by means of $\ensuremath{\beta}$-neutron-$\ensuremath{\Gamma}$ Spectroscopy. An isotopically pure $^{86}\mathrm{Ga}$ beam was produced at the Holifield Radioactive Ion Beam Facility using a resonance ionization laser ion source and high-resolution electromagnetic separation. The decay of $^{86}\mathrm{Ga}$ revealed a half-life of ${43}_{\ensuremath{-}15}^{+21}\text{ }\text{ }\mathrm{ms}$ and large $\ensuremath{\beta}$-delayed one-neutron and two-neutron branching ratios of ${P}_{1n}=60(10)%$ and ${P}_{2n}=20(10)%$. The $\ensuremath{\beta}\ensuremath{\Gamma}$ decay of $^{86}\mathrm{Ga}$ populated a 527 keV transition that is interpreted as the deexcitation of the first ${2}^{+}$ state in the $N=54$ isotone $^{86}\mathrm{Ge}$ and suggests a quick onset of deformation in Ge isotopes beyond $N=50$.
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large β delayed one and two neutron emission rates in the decay of 86ga
Physical Review Letters, 2013Co-Authors: K P Rykaczewski, K Miernik, R Grzywacz, C J Gross, M Madurga, David H Miller, J C Batchelder, I N BorzovAbstract:Beta decay of $^{86}\mathrm{Ga}$ was studied by means of $\ensuremath{\beta}$-neutron-$\ensuremath{\Gamma}$ Spectroscopy. An isotopically pure $^{86}\mathrm{Ga}$ beam was produced at the Holifield Radioactive Ion Beam Facility using a resonance ionization laser ion source and high-resolution electromagnetic separation. The decay of $^{86}\mathrm{Ga}$ revealed a half-life of ${43}_{\ensuremath{-}15}^{+21}\text{ }\text{ }\mathrm{ms}$ and large $\ensuremath{\beta}$-delayed one-neutron and two-neutron branching ratios of ${P}_{1n}=60(10)%$ and ${P}_{2n}=20(10)%$. The $\ensuremath{\beta}\ensuremath{\Gamma}$ decay of $^{86}\mathrm{Ga}$ populated a 527 keV transition that is interpreted as the deexcitation of the first ${2}^{+}$ state in the $N=54$ isotone $^{86}\mathrm{Ge}$ and suggests a quick onset of deformation in Ge isotopes beyond $N=50$.
Paulo Magalhaes Martins - One of the best experts on this subject based on the ideXlab platform.
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prompt Gamma Spectroscopy for absolute range verification of 12c ions at synchrotron based facilities
Physics in Medicine and Biology, 2020Co-Authors: Riccardo Dal Bello, Paulo Magalhaes Martins, S Brons, G Hermann, T Kihm, M Seimetz, J SecoAbstract:The physical range uncertainty limits the exploitation of the full potential of charged particle therapy. In this work, we face this issue aiming to measure the absolute Bragg peak position in the target. We investigate p, 4He, 12C and 16O beams accelerated at the Heidelberg Ion-Beam Therapy Center. The residual range of the primary 12C ions is correlated to the energy spectrum of the prompt Gamma radiation. The prompt Gamma Spectroscopy method was demonstrated for proton beams accelerated by cyclotrons and is developed here for the first time for heavier ions accelerated by a synchrotron. We develop a detector system that includes (i) a spectroscopic unit based on cerium(III) bromide and bismuth germanium oxide scintillating crystals, (ii) a beam trigger based on an array of scintillating fibers and (iii) a data acquisition system based on a FlashADC. We test the system in two different scenarios. In the first series of experiments, we detect and identify 19 independent spectral lines over a wide Gamma energy spectrum in the presence of the four ion species for different targets, including a water target with a titanium insert. In the second series of experiments, we introduce a collimator aiming to relate the spectral information to the range of the primary particles. We perform extensive measurements for a 12C beam and demonstrate submillimetric precision for the measurement of its Bragg peak position in the experimental setup. The features of the energy and time spectra for Gamma radiation induced by p, 4He and 16O are investigated upstream and downstream from the Bragg peak position. We conclude the analysis by extrapolating the required future developments, which would be needed to achieve range verification with a 2 mm accuracy during a single fraction delivery of [Formula: see text] physical dose.
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results from the experimental evaluation of cebr scintillators for he prompt Gamma Spectroscopy
Medical Physics, 2019Co-Authors: Riccardo Dal Bello, Paulo Magalhaes Martins, G Hermann, T Kihm, J Seco, Joao GracaAbstract:Purpose The presence of range uncertainties hinders the exploitation of the full potential of charged particle therapy. Several range verification techniques have been proposed to mitigate this limitation. Prompt Gamma Spectroscopy (PGS) is among the most promising solutions for online and in vivo range verification. In this work, we present the experimental results of the detection of prompt Gamma radiation, induced by 4 He beams at the Heidelberg Ion-Beam Therapy Center (HIT). The results were obtained, using a spectroscopic unit of which the design has been optimized using Monte Carlo simulations. Methods The spectroscopic unit is composed by a primary cerium bromide (CeBr 3 ) crystal surrounded by a secondary bismuth germanate (BGO) crystal for anticoincidence detection (AC). The digitalization of the signals is performed with an advanced FADC/FPGA system. The 4 He beams at clinical energies and intensities are delivered to multiple targets in the experimental cave at the HIT. We analyze the production of prompt Gamma on oxygen and carbon targets, as well as high Z materials such as titanium and aluminum. The quantitative analysis includes a systematic comparison of the signal-to-noise ratio (SNR) improvement for the spectral lines when introducing the AC detection. Moreover, the SNR improvement could provide a reduction of the number of events required to draw robust conclusions. We perform a statistic analysis to determine the magnitude of such an effect. Results We present the energy spectra detected by the primary CeBr 3 and the secondary BGO. The combination of these two detectors leads to an average increase of the signal-to-noise ratio by a factor 2.1, which confirms the Monte Carlo predictions. The spectroscopic unit is capable of detecting efficiently the discrete Gamma emission over the full energy spectrum. We identify and analyze 19 independent spectral lines in an energy range spacing from E γ = 0.718 MeV to E γ = 6.13 MeV. Moreover, when introducing the AC detection, the number of events required to determine robustly the intensity of the discrete lines decreases. Finally, the analysis of the low-energy reaction lines determines whether a thin metal insert is introduced in the beam direction. Conclusions This work provides the experimental characterization of the Spectroscopy unit in development for range verification through PGS at the HIT. Excellent performances have been demonstrated over the full prompt Gamma energy spectrum with 4 He beams at clinical energies and intensities.
