Driving of the nuclear fusion reaction p+^(11)B3α+8.7 MeV under laboratory conditions by interaction between high-power laser pulses and matter has become a popular field of research,owing to its numerous potential a...Driving of the nuclear fusion reaction p+^(11)B3α+8.7 MeV under laboratory conditions by interaction between high-power laser pulses and matter has become a popular field of research,owing to its numerous potential applications:as an alternative to deuterium-tritium for fusion energy production,astrophysics studies,and alpha-particle generation for medical treatment.One possible scheme for laser-driven p-^(11)B reactions is to direct a beam of laser-accelerated protons onto a boron(B)sample(the so-called“pitcher-catcher”scheme).This technique has been successfully implemented on large high-energy lasers,yielding hundreds of joules per shot at low repetition.We present here a complementary approach,exploiting the high repetition rate of the VEGA III petawatt laser at CLPU(Spain),aiming at accumulating results from many interactions at much lower energy,to provide better control of the parameters and the statistics of the measurements.Despite a moderate energy per pulse,our experiment allowed exploration of the laser-driven fusion process with tens(up to hundreds)of laser shots.The experiment provided a clear signature of the reactions involved and of the fusion products,accumulated over many shots,leading to an improved optimization of the diagnostics for experimental campaigns of this type.In this paper,we discuss the effectiveness of laser-driven p-11B fusion in the pitcher-catcher scheme,at a high repetition rate,addressing the challenges of this experimental scheme and highlighting its critical aspects.Our proposed methodology allows evaluation of the performance of this scheme for laser-driven alpha particle production and can be adapted to high-repetition-rate laser facilities with higher energy and intensity.展开更多
The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few micrometer...The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few micrometers.Protons with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary targets.Under such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical application.The use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on accelerators.In this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other applications.At the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy production.The experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,Spain.Angular distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium detector.Our results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[Nucl.Instrum.Methods Phys.Res.,Sect.A 637,164–170(2011)].展开更多
Heavy ion collisions near the Fermi energy produce a‘freezout’region where fragments appear and later decay,emitting mainly neutrons,protons,alpha particles,and gamma rays.These decay products carry information abou...Heavy ion collisions near the Fermi energy produce a‘freezout’region where fragments appear and later decay,emitting mainly neutrons,protons,alpha particles,and gamma rays.These decay products carry information about the decaying nuclei.Fragmentation events may result in high yields of boson particles,especially alpha particles,and may carry important information about the nuclear Bose Einstein condensate(BEC).We study‘in medium’fourαcorrelations and link them to the‘fission’of 16O in two 8Be in the ground state or 12C*(Hoyle state)+α.Using novel techniques for the correlation functions,we confirm the resonance of 16O at 15.2 MeV excitation energy,and the possibility of a lower resonance,close to 14.72 MeV.The latter resonance is the result of allαparticles having 92 keV relative kinetic energies.展开更多
The Efimov(Thomas) trimers in excited 12 C nuclei, for which no observation exists yet, are discussed by means of analyzing the experimental data of 70(64)Zn(64 Ni)+ 70(64)Zn(64 Ni) reactions at the beam energy of E/A...The Efimov(Thomas) trimers in excited 12 C nuclei, for which no observation exists yet, are discussed by means of analyzing the experimental data of 70(64)Zn(64 Ni)+ 70(64)Zn(64 Ni) reactions at the beam energy of E/A = 35 MeV/nucleon. In heavy ion collisions, a-particles interact with each other and can form complex systems such as 8 Be and 12 C. For the 3 a-particle systems,multi-resonance processes give rise to excited levels of 12 C. The interaction between any two of the 3 a-particles provides events with one, two or three 8 Be. Their interfering levels are clearly seen in the minimum relative energy distributions. Events with the three a-particle relative energies consistent with the ground state of 8 Be are observed with the decrease of the instrumental error for the reconstructed 7.458 MeV excitation level in 12 C, which was suggested as the Efimov(Thomas) state.展开更多
基金funded by the European Union via the Euratom Research and Training Program(Grant Agreement No.101052200-EUROfusion)funding from LASERLAB-EUROPE(Grant Agreement No.871124,European Union’s Horizon 2020 Research and Innovation Program)+5 种基金supported in part by the United States Department of Energy under Grant No.DE-FG02-93ER40773We also acknowledge support from Grant No.PID2021-125389OA-I00 funded by MCIN/AEI/10.13039/501100011033/FEDER,UEby“ERDF A Way of Making Europe”by the European Union and Unidad de Investigación Consolidada of Junta de Castilla y León UIC 167supported in part by the National Natural Science Foundation of China under Grant No.12375125the Fundamental Research Funds for the Central Universitiesthe support of the Czech Science Foundation through Grant No.GACR24-11398S.
文摘Driving of the nuclear fusion reaction p+^(11)B3α+8.7 MeV under laboratory conditions by interaction between high-power laser pulses and matter has become a popular field of research,owing to its numerous potential applications:as an alternative to deuterium-tritium for fusion energy production,astrophysics studies,and alpha-particle generation for medical treatment.One possible scheme for laser-driven p-^(11)B reactions is to direct a beam of laser-accelerated protons onto a boron(B)sample(the so-called“pitcher-catcher”scheme).This technique has been successfully implemented on large high-energy lasers,yielding hundreds of joules per shot at low repetition.We present here a complementary approach,exploiting the high repetition rate of the VEGA III petawatt laser at CLPU(Spain),aiming at accumulating results from many interactions at much lower energy,to provide better control of the parameters and the statistics of the measurements.Despite a moderate energy per pulse,our experiment allowed exploration of the laser-driven fusion process with tens(up to hundreds)of laser shots.The experiment provided a clear signature of the reactions involved and of the fusion products,accumulated over many shots,leading to an improved optimization of the diagnostics for experimental campaigns of this type.In this paper,we discuss the effectiveness of laser-driven p-11B fusion in the pitcher-catcher scheme,at a high repetition rate,addressing the challenges of this experimental scheme and highlighting its critical aspects.Our proposed methodology allows evaluation of the performance of this scheme for laser-driven alpha particle production and can be adapted to high-repetition-rate laser facilities with higher energy and intensity.
文摘The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few micrometers.Protons with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary targets.Under such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical application.The use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on accelerators.In this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other applications.At the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy production.The experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,Spain.Angular distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium detector.Our results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[Nucl.Instrum.Methods Phys.Res.,Sect.A 637,164–170(2011)].
基金Supported by the National Natural Science Foundation of China(11765014,11865010,11905120,I1605097,U2032146,11421505)the Robert A.Welch Founda-tion(A-1266)+6 种基金the US Department of Energy(DE-FG02-93ER40773)Natural Science Foundation of Inner Mongolia(2018MS01009,20191001)the Chinese Academy of Sciences(CAS)President's International Fellowship Initiative(2015VW A070)the Strategic Priority Research Program of the Chinese Academy of Sci-ences(XDB16,XDPB09)the Program for Young Talents of Science and Technology in Univrities of Inmer Mongolia Autonomous Region(NJYT-18-B21)the Doctoral Seientifie Research Foundation of Inner Mongolia University for Nationalities(BS365.BS400)The Fundamental Research Funds for the Central University(GK201903022)。
文摘Heavy ion collisions near the Fermi energy produce a‘freezout’region where fragments appear and later decay,emitting mainly neutrons,protons,alpha particles,and gamma rays.These decay products carry information about the decaying nuclei.Fragmentation events may result in high yields of boson particles,especially alpha particles,and may carry important information about the nuclear Bose Einstein condensate(BEC).We study‘in medium’fourαcorrelations and link them to the‘fission’of 16O in two 8Be in the ground state or 12C*(Hoyle state)+α.Using novel techniques for the correlation functions,we confirm the resonance of 16O at 15.2 MeV excitation energy,and the possibility of a lower resonance,close to 14.72 MeV.The latter resonance is the result of allαparticles having 92 keV relative kinetic energies.
基金Supported by the National Natural Science Foundation of China(1176014,11605097,11421505,11865010)the US Department of Energy(DE-FG02-93ER40773,NNSA DE-NA0003841(CENTAUR))+6 种基金the Robert A.Welch Foundation(A-1266)supported by the Chinese Academy of Sciences(CAS)President’s International Fellowship Initiative(2015VWA070)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB16 and XDPB09)Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(NJYT-18-B21)Doctoral Scientific Research Foundation of Inner Mongolia University for Nationalities(BS365 and BS400)The Fundamental Research Funds for the Central Universities(GK201903022)Natural Science Foundation of Inner Mongolia(2018MS01009)
文摘The Efimov(Thomas) trimers in excited 12 C nuclei, for which no observation exists yet, are discussed by means of analyzing the experimental data of 70(64)Zn(64 Ni)+ 70(64)Zn(64 Ni) reactions at the beam energy of E/A = 35 MeV/nucleon. In heavy ion collisions, a-particles interact with each other and can form complex systems such as 8 Be and 12 C. For the 3 a-particle systems,multi-resonance processes give rise to excited levels of 12 C. The interaction between any two of the 3 a-particles provides events with one, two or three 8 Be. Their interfering levels are clearly seen in the minimum relative energy distributions. Events with the three a-particle relative energies consistent with the ground state of 8 Be are observed with the decrease of the instrumental error for the reconstructed 7.458 MeV excitation level in 12 C, which was suggested as the Efimov(Thomas) state.
