Based on the facility of the Shanghai Laser Electron Gamma Source （SLEGS）, the transmutation for nuclear wastes such as 137^Cs and 129^I is investigated. It is found that nuclear waste can be transmuted efficiently ...Based on the facility of the Shanghai Laser Electron Gamma Source （SLEGS）, the transmutation for nuclear wastes such as 137^Cs and 129^I is investigated. It is found that nuclear waste can be transmuted efficiently via photonuclear reaction triggered by gamma photons generated from Compton backscattering between CO2 laser photons and 3.5 GeV electrons. The nuclear activities of 137^Cs and 129^I are evaluated and compared with the results of transmutation triggered by bremsstrahlung gamma photons driven by ultra intense laser. Due to the better character of gamma photon spectrum as well as the high brightness of gamma photons, the transmutation rate of Compton backscattering method is much higher than that of the bremsstrahlung method.展开更多
The beam energy is measured in the e^＋e^- collision by using Compton backscattering. The uncertainty of this measurement process is studied by virtue of analytical formulas, and the special effects of variant energy ...The beam energy is measured in the e^＋e^- collision by using Compton backscattering. The uncertainty of this measurement process is studied by virtue of analytical formulas, and the special effects of variant energy spread and energy drift on the systematic uncertainty estimation are also studied with the Monte Carlo sampling technique. These quantitative conclusions are especially important for understanding the uncertainty of the beam energy measurement system.展开更多
Recently we have constructed two facilities for generating photon beams in the MeV and sub-MeV energy regions by means of the Compton backscattering with a laser and an electron beam at SPring-8 and at Kansai Photon S...Recently we have constructed two facilities for generating photon beams in the MeV and sub-MeV energy regions by means of the Compton backscattering with a laser and an electron beam at SPring-8 and at Kansai Photon Science Institute of Japan Atomic Energy Agency(KPSI-JAEA). The MeV-photon source at SPring-8 consists of a continuous-wave optically-pumped far infrared laser with a wavelength of 118.8 μm and an 8 GeV stored electron beam. Present MeV-photon flux is estimated to be 1.3×103 photons/s. On the other hand,the sub-MeV-photon source at KPSI-JAEA consists of a pulse Nd∶YAG laser with a wavelength of 1 064 nm and a 150 MeV electron beam accelerated by microtron. In the first trial of the photon production in this source,backscattered photon flux is estimated to be 20 photons/pulse. Both the Compton backscattered photon sources have possibilities to be used for new tools in various fields such as nuclear physics,materials science,and astronomy.展开更多
A diamond-like carbon circular target is proposed to improve γ-ray emission and pair production with a laser intensity of 8×1022 W cm-2by using 2D particle-in-cell simulations with quantum electrodynamics.It is ...A diamond-like carbon circular target is proposed to improve γ-ray emission and pair production with a laser intensity of 8×1022 W cm-2by using 2D particle-in-cell simulations with quantum electrodynamics.It is found that the circular target can enhance the density of γ-photons significantly more than a plane target, when two colliding circularly polarized lasers irradiate the target.By multi-laser irradiating the circular target, the optical trap of lasers can prevent the high energy electrons accelerated by laser radiation pressure from escaping.Hence, γ-photons with a high density of beyond 5000 ncare obtained through nonlinear Compton backscattering.Meanwhile, 2.7×1011 positrons with an average energy of 230 MeV are achieved via the multiphoton Breit-Wheeler process.Such an ultrabright γ-ray source and dense positron source can be useful in many applications.The optimal target radius and laser mismatching deviation parameters are also discussed in detail.展开更多
基金Knowledge Innovation Project of Chinese Academy of Sciences (KJCX2-SW-N13)China Postdoctoral ScienceFoundation, National Natural Science Foundation of China (10475108, 10605036, 10405032)+1 种基金One Hundred Person Project of SINAPShanghai Development Foundation for Science and Technology (06QA14062)
文摘Based on the facility of the Shanghai Laser Electron Gamma Source （SLEGS）, the transmutation for nuclear wastes such as 137^Cs and 129^I is investigated. It is found that nuclear waste can be transmuted efficiently via photonuclear reaction triggered by gamma photons generated from Compton backscattering between CO2 laser photons and 3.5 GeV electrons. The nuclear activities of 137^Cs and 129^I are evaluated and compared with the results of transmutation triggered by bremsstrahlung gamma photons driven by ultra intense laser. Due to the better character of gamma photon spectrum as well as the high brightness of gamma photons, the transmutation rate of Compton backscattering method is much higher than that of the bremsstrahlung method.
基金Supported by National Natural Science Foundation of China(NSFC)(11375206,10775142,10825524,11125525,11235011)
文摘The beam energy is measured in the e^＋e^- collision by using Compton backscattering. The uncertainty of this measurement process is studied by virtue of analytical formulas, and the special effects of variant energy spread and energy drift on the systematic uncertainty estimation are also studied with the Monte Carlo sampling technique. These quantitative conclusions are especially important for understanding the uncertainty of the beam energy measurement system.
基金Japan Societyfor Promotion of Science under Grant-and Aid for Scientific Research(14205018)Ministry of Educa-tion,Science,Sports and Culture of Japan under Grant-and-Aid for Specially Promoted Research (15002013)
文摘Recently we have constructed two facilities for generating photon beams in the MeV and sub-MeV energy regions by means of the Compton backscattering with a laser and an electron beam at SPring-8 and at Kansai Photon Science Institute of Japan Atomic Energy Agency(KPSI-JAEA). The MeV-photon source at SPring-8 consists of a continuous-wave optically-pumped far infrared laser with a wavelength of 118.8 μm and an 8 GeV stored electron beam. Present MeV-photon flux is estimated to be 1.3×103 photons/s. On the other hand,the sub-MeV-photon source at KPSI-JAEA consists of a pulse Nd∶YAG laser with a wavelength of 1 064 nm and a 150 MeV electron beam accelerated by microtron. In the first trial of the photon production in this source,backscattered photon flux is estimated to be 20 photons/pulse. Both the Compton backscattered photon sources have possibilities to be used for new tools in various fields such as nuclear physics,materials science,and astronomy.
基金supported by the National Natural Science Foundation of China (Nos.11875007, 11305010)supported by the STFC Cockcroft Institute core grant
文摘A diamond-like carbon circular target is proposed to improve γ-ray emission and pair production with a laser intensity of 8×1022 W cm-2by using 2D particle-in-cell simulations with quantum electrodynamics.It is found that the circular target can enhance the density of γ-photons significantly more than a plane target, when two colliding circularly polarized lasers irradiate the target.By multi-laser irradiating the circular target, the optical trap of lasers can prevent the high energy electrons accelerated by laser radiation pressure from escaping.Hence, γ-photons with a high density of beyond 5000 ncare obtained through nonlinear Compton backscattering.Meanwhile, 2.7×1011 positrons with an average energy of 230 MeV are achieved via the multiphoton Breit-Wheeler process.Such an ultrabright γ-ray source and dense positron source can be useful in many applications.The optimal target radius and laser mismatching deviation parameters are also discussed in detail.
