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
The supersonic gas-jet target is an important experimental target for laser wakefield acceleration(LWFA),which has great potential for driving novel radiation sources such as betatron radiation and Compton scattering ...The supersonic gas-jet target is an important experimental target for laser wakefield acceleration(LWFA),which has great potential for driving novel radiation sources such as betatron radiation and Compton scattering gamma rays.According to different electron acceleration requirements,it is necessary to provide specific supersonic gas jets with different density profiles to generate electron beams with high quality and high repetition rates.In this study,the interference images and density profiles of different gas-jet targets were obtained through a modified Nomarski interference diagnosis system.The relationships between the gas density and back pressure,nozzle structure,and other key parameters were studied.Targets with different characteristics are conducive to meeting the various requirements of LWFA.展开更多
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This work was supported by the Programs for the National Natural Science Foundation of China(Nos.11975316,11775312,12005305 and 61905287)the Continue Basic Scientific Research Project(Nos.WDJC-2019-02 and BJ20002501).
文摘The supersonic gas-jet target is an important experimental target for laser wakefield acceleration(LWFA),which has great potential for driving novel radiation sources such as betatron radiation and Compton scattering gamma rays.According to different electron acceleration requirements,it is necessary to provide specific supersonic gas jets with different density profiles to generate electron beams with high quality and high repetition rates.In this study,the interference images and density profiles of different gas-jet targets were obtained through a modified Nomarski interference diagnosis system.The relationships between the gas density and back pressure,nozzle structure,and other key parameters were studied.Targets with different characteristics are conducive to meeting the various requirements of LWFA.
