ABSTRACT Aneutronic fusion reactions such as proton-boron fusion could efficiently produce clean energy with quite low neutron doses.However,as a consequence,conventional neutron spectral methods for diagnosing plasma...ABSTRACT Aneutronic fusion reactions such as proton-boron fusion could efficiently produce clean energy with quite low neutron doses.However,as a consequence,conventional neutron spectral methods for diagnosing plasma ion temperature would no longer work.Therefore,finding a way to probe the ion temperature in aneutronic fusion plasmas is a crucial task.Here,we present a method to realize ultrafast in situ probing of^(11)B ion temperature for proton-boron fusion by Doppler broadening of the nuclear resonance fluorescence(NRF)emission spectrum.The NRF emission is excited by a collimated,intenseγ-ray beam generated from submicrometer wires irradiated by a recently available petawatt(PW)laser pulse,where theγ-ray beam generation is calculated by three-dimensional particle-in-cell simulation.When the laser power is higher than 1 PW,five NRF signatures of a^(11)B plasma can be clearly identified with high-resolutionγ-ray detectors,as shown by our Geant4 simulations.The correlation between the NRF peak width and^(11)B ion temperature is discussed,and it is found that NRF emission spectroscopy should be sensitive to 11B ion temperatures T_(i)>2.4 keV.This probing method can also be extended to other neutron-free-fusion isotopes,such as^(6)Li and^(15)N.展开更多
基金the National Natural Science Foundation of China(Grant Nos.11675075 and 11775302)the Youth Talent Project of Hunan Province,China(Grant No.2018RS3096)+4 种基金the Independent Research Project of the Key Laboratory of Plasma Physics,CAEP(Grant No.JCKYS2021212009)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA25050300)the National Key R&D Program of China(Grant No.2018YFA0404801)the Research Project of NUDT(Grant No.ZK18-02-02)the Fundamental Research Funds for the Central Universities,the Research Funds of Renmin University of China(Grant No.20XNLG01).
文摘ABSTRACT Aneutronic fusion reactions such as proton-boron fusion could efficiently produce clean energy with quite low neutron doses.However,as a consequence,conventional neutron spectral methods for diagnosing plasma ion temperature would no longer work.Therefore,finding a way to probe the ion temperature in aneutronic fusion plasmas is a crucial task.Here,we present a method to realize ultrafast in situ probing of^(11)B ion temperature for proton-boron fusion by Doppler broadening of the nuclear resonance fluorescence(NRF)emission spectrum.The NRF emission is excited by a collimated,intenseγ-ray beam generated from submicrometer wires irradiated by a recently available petawatt(PW)laser pulse,where theγ-ray beam generation is calculated by three-dimensional particle-in-cell simulation.When the laser power is higher than 1 PW,five NRF signatures of a^(11)B plasma can be clearly identified with high-resolutionγ-ray detectors,as shown by our Geant4 simulations.The correlation between the NRF peak width and^(11)B ion temperature is discussed,and it is found that NRF emission spectroscopy should be sensitive to 11B ion temperatures T_(i)>2.4 keV.This probing method can also be extended to other neutron-free-fusion isotopes,such as^(6)Li and^(15)N.
