High energy γ-rays can be used in many fields, such as nuclear waste transmutation, flash photographics, and astrophysics. The13 C(p, γ)14 N resonance reaction was used to generate high energy and mono-energetic γ-...High energy γ-rays can be used in many fields, such as nuclear waste transmutation, flash photographics, and astrophysics. The13 C(p, γ)14 N resonance reaction was used to generate high energy and mono-energetic γ-rays in this work. The thick-target yield of the 9.17-MeV γ-ray from the resonance in this reaction was determined to be(4.7±0.4)×10-9γ/proton,which was measured by a HPGe detector. Meanwhile, the angular distribution of 9.17-MeV γ-ray was also determined.The absolute efficiency of HPGe detector was calibrated using56 Co and152 Eu sources with known radioactive activities and calculated by GEANT4 simulation.展开更多
It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,...It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,p)3H,one of the most crucial reactions in big bang nucleosynthesis models,at the Shenguang-Ⅱlaser facility.In this work,we present a new calibration of CR-39 solidstate track detectors,which are widely employed as the main diagnostics in this type of fusion reaction experiment.We measure the dependence of the track diameter on the proton energy.It is found that the track diameters of protons with different energies are likely to be identical.We propose that in this case,the energy of the reaction products can be obtained by considering both the diameters and gray levels of these tracks.The present results would be very helpful for analyzing the2 H(d,p)3H reaction products recorded with the same batch of CR-39 solid-state track detectors.展开更多
Based on the LINAC of BEPCII, a high-polarized, high bightness, energy-tunable, monoenergetic laser compton backscattering (LCS)gamma-ray source is under construction at IHEP. The gamma-ray energy range is from 1 MeV ...Based on the LINAC of BEPCII, a high-polarized, high bightness, energy-tunable, monoenergetic laser compton backscattering (LCS)gamma-ray source is under construction at IHEP. The gamma-ray energy range is from 1 MeV to 111 MeV. It is a powerful and hopeful researchplatform to reveal the underlying physics of the nuclear, the basic particles and the vacuum or to check the exist basic physical models, quantumelectrodynamic (QED) theories. In the platform, a 1.064 mm Nd:YAG laser system and a 10.6 mm CO_(2) laser system are employed. All the triggersignals to the laser system and the electron control system are from the only reference clock at the very beginning of the LINAC to make sure thetemporal synchronization. Two optical transition radiation (OTR) targets and two charged-couple devices (CCD) are used to monitor and to alignthe electron beam and the laser beam. With the LCS gamma-ray source, it is proposed to experimentally check the gamma-ray calibrations, thephoton-nuclear physics, nuclear astrophysics and some basic QED phenomena.展开更多
High intensity γ-ray source can be obtained through resonance reaction induced by protons. In this work, the possibility of using such high intensity MeV-range γ-ray source to transmute nuclear waste is investigated...High intensity γ-ray source can be obtained through resonance reaction induced by protons. In this work, the possibility of using such high intensity MeV-range γ-ray source to transmute nuclear waste is investigated through Mont Carlo simulation.197 Au(γ, n)196Au experiment is performed to obtain the transmutation rate and compared with the simulation result. If the current of the proton beam is 10 mA at the resonance energy of 441 keV, with the γ photons emitted from7 Li(p, γ)8 Be, then the corresponding transmutation yield for129I in 2π direction can reach 9.4 × 109 per hour. The result is compared with that of LCS γ-ray source.展开更多
High energy γ-ray can be used for nuclear waste transmutation by using the giant dipole resonance(GDR). The photonuclear reaction 197Au(γ, n) is known as a standard for studies on photoactivation experiments. The pr...High energy γ-ray can be used for nuclear waste transmutation by using the giant dipole resonance(GDR). The photonuclear reaction 197Au(γ, n) is known as a standard for studies on photoactivation experiments. The previous experiments on 197Au(γ, n) have been performed with bremsstrahlung, positron annihilation in flight or laser Compton scattering γ-ray.In this work, a new mono-energetic γ-ray source based on 13C(p,γ)^14N reaction is used to measure the cross section of 197Au(γ, n) and the measured value is compared with the results obtained with other ways.展开更多
High energyγ-ray can be used in many fields,such as nuclear resonant fluorescence,nuclear medicine imaging.One of the methods to generate high-energyγ-ray is nuclear resonant reaction.The 19F(p,αγ)16O reaction was...High energyγ-ray can be used in many fields,such as nuclear resonant fluorescence,nuclear medicine imaging.One of the methods to generate high-energyγ-ray is nuclear resonant reaction.The 19F(p,αγ)16O reaction was used to generate 6.13-MeVγ-ray in this work.The angular distribution of 6.13-MeVγ-ray was measured by six LaBr3 detectors.The thick-target yield curve of 6.13-MeVγ-ray had been measured.The maximum yield was determined to be(1.85±0.01)×10^-8γ/proton,which was measured by HPGe detector and LaBr3 detector.The absolute efficiency of all the detectors was calibrated using 60Co and 27Al(p,γ)^28Si reaction at Ep=992 keV.The cross section and total resonant width of the reaction were determined to be 95.1±1.0 mb(1 b=10^-24 cm^2)andΓCM=2.21±0.22 keV,respectively.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11655003)
文摘High energy γ-rays can be used in many fields, such as nuclear waste transmutation, flash photographics, and astrophysics. The13 C(p, γ)14 N resonance reaction was used to generate high energy and mono-energetic γ-rays in this work. The thick-target yield of the 9.17-MeV γ-ray from the resonance in this reaction was determined to be(4.7±0.4)×10-9γ/proton,which was measured by a HPGe detector. Meanwhile, the angular distribution of 9.17-MeV γ-ray was also determined.The absolute efficiency of HPGe detector was calibrated using56 Co and152 Eu sources with known radioactive activities and calculated by GEANT4 simulation.
基金This work was supported by the National Key Research and Development Project(No.2016YFA0400502)the National Natural Science Foundation of China(No.11775312).
文摘It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,p)3H,one of the most crucial reactions in big bang nucleosynthesis models,at the Shenguang-Ⅱlaser facility.In this work,we present a new calibration of CR-39 solidstate track detectors,which are widely employed as the main diagnostics in this type of fusion reaction experiment.We measure the dependence of the track diameter on the proton energy.It is found that the track diameters of protons with different energies are likely to be identical.We propose that in this case,the energy of the reaction products can be obtained by considering both the diameters and gray levels of these tracks.The present results would be very helpful for analyzing the2 H(d,p)3H reaction products recorded with the same batch of CR-39 solid-state track detectors.
基金This work was supported by National Natural Science Foundation of China(11655003)Innovation Project of IHEP(542017IHEPZZBS11820)This work was supported in part by the CAS Center for Excellence in Particle Physics(CCEPP).
文摘Based on the LINAC of BEPCII, a high-polarized, high bightness, energy-tunable, monoenergetic laser compton backscattering (LCS)gamma-ray source is under construction at IHEP. The gamma-ray energy range is from 1 MeV to 111 MeV. It is a powerful and hopeful researchplatform to reveal the underlying physics of the nuclear, the basic particles and the vacuum or to check the exist basic physical models, quantumelectrodynamic (QED) theories. In the platform, a 1.064 mm Nd:YAG laser system and a 10.6 mm CO_(2) laser system are employed. All the triggersignals to the laser system and the electron control system are from the only reference clock at the very beginning of the LINAC to make sure thetemporal synchronization. Two optical transition radiation (OTR) targets and two charged-couple devices (CCD) are used to monitor and to alignthe electron beam and the laser beam. With the LCS gamma-ray source, it is proposed to experimentally check the gamma-ray calibrations, thephoton-nuclear physics, nuclear astrophysics and some basic QED phenomena.
基金Project supported by the National Natural Science Foundation of China(Grant No.11655003)
文摘High intensity γ-ray source can be obtained through resonance reaction induced by protons. In this work, the possibility of using such high intensity MeV-range γ-ray source to transmute nuclear waste is investigated through Mont Carlo simulation.197 Au(γ, n)196Au experiment is performed to obtain the transmutation rate and compared with the simulation result. If the current of the proton beam is 10 mA at the resonance energy of 441 keV, with the γ photons emitted from7 Li(p, γ)8 Be, then the corresponding transmutation yield for129I in 2π direction can reach 9.4 × 109 per hour. The result is compared with that of LCS γ-ray source.
基金Project supported by the National Natural Science Foundation of China(Grant No.11655003)
文摘High energy γ-ray can be used for nuclear waste transmutation by using the giant dipole resonance(GDR). The photonuclear reaction 197Au(γ, n) is known as a standard for studies on photoactivation experiments. The previous experiments on 197Au(γ, n) have been performed with bremsstrahlung, positron annihilation in flight or laser Compton scattering γ-ray.In this work, a new mono-energetic γ-ray source based on 13C(p,γ)^14N reaction is used to measure the cross section of 197Au(γ, n) and the measured value is compared with the results obtained with other ways.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFA0400502)the National Natural Science Foundation of China(Grant Nos.11975316 and 11655003)the Continuous Basic Research Project of China(Grant No.WDJC-2019-02).
文摘High energyγ-ray can be used in many fields,such as nuclear resonant fluorescence,nuclear medicine imaging.One of the methods to generate high-energyγ-ray is nuclear resonant reaction.The 19F(p,αγ)16O reaction was used to generate 6.13-MeVγ-ray in this work.The angular distribution of 6.13-MeVγ-ray was measured by six LaBr3 detectors.The thick-target yield curve of 6.13-MeVγ-ray had been measured.The maximum yield was determined to be(1.85±0.01)×10^-8γ/proton,which was measured by HPGe detector and LaBr3 detector.The absolute efficiency of all the detectors was calibrated using 60Co and 27Al(p,γ)^28Si reaction at Ep=992 keV.The cross section and total resonant width of the reaction were determined to be 95.1±1.0 mb(1 b=10^-24 cm^2)andΓCM=2.21±0.22 keV,respectively.