With the much-anticipated multi-petawatt(PW)laser facilities that are coming online,neutron sources with extreme fluxes could soon be in reach.Such sources would rely on spallation by protons accelerated by the high-i...With the much-anticipated multi-petawatt(PW)laser facilities that are coming online,neutron sources with extreme fluxes could soon be in reach.Such sources would rely on spallation by protons accelerated by the high-intensity lasers.These high neutron fluxes would make possible not only direct measurements of neutron capture andβ-decay rates related to the r-process of nucleosynthesis of heavy elements,but also such nuclear measurements in a hot plasma environment,which would be beneficial for s-process investigations in astrophysically relevant conditions.This could,in turn,finally allow possible reconciliation of the observed element abundances in stars and those derived from simulations,which at present show large discrepancies.Here,we review a possible pathway to reach unprecedented neutron fluxes using multi-PW lasers,as well as strategies to perform measurements to investigate the r-and s-processes of nucleosynthesis of heavy elements in cold matter,as well as in a hot plasma environment.展开更多
We present the results of the first commissioning phase of the short-focal-length area of the Apollon laser facility(located in Saclay,France),which was performed with the first available laser beam(F2),scaled to a no...We present the results of the first commissioning phase of the short-focal-length area of the Apollon laser facility(located in Saclay,France),which was performed with the first available laser beam(F2),scaled to a nominal power of 1 PW.Under the conditions that were tested,this beam delivered on-target pulses of 10 J average energy and 24 fs duration.Several diagnostics were fielded to assess the performance of the facility.The on-target focal spot and its spatial stability,the temporal intensity profile prior to the main pulse,and the resulting density gradient formed at the irradiated side of solid targets have been thoroughly characterized,with the goal of helping users design future experiments.Emissions of energetic electrons,ions,and electromagnetic radiation were recorded,showing good laser-to-target coupling efficiency and an overall performance comparable to that of similar international facilities.This will be followed in 2022 by a further commissioning stage at the multipetawatt level.展开更多
基金We acknowledge fruitful discussions with H.P´epin(INRS),V.M´eot,L.Gremillet,X.Davoine(CEA),S.Orlando(INAF),C.Guerrero(Universidad de Sevilla),and Y.Caristan(Universit´e Paris-Saclay).This project received funding from the European Research Council(ERC)under the European Union’s Horizon 2020 Research and Innovation Programme(Grant Agreement No.787539),and was partly conducted within the LABEX Plas@Par project and supported by Grant Nos.11-IDEX-0004-02 and an ANR-17-CE30-0026 PiNNaCLE grant from Agence Nationale de la Recherche(France).I.P.acknowledges the support of ISF Grant No.1135/15.The research leading to these results is supported by Extreme Light Infrastructure Nuclear Physics(ELI-NP)Phase I,a project cofinanced by the Romanian Government and the European Union through the European Regional Development Fund.
文摘With the much-anticipated multi-petawatt(PW)laser facilities that are coming online,neutron sources with extreme fluxes could soon be in reach.Such sources would rely on spallation by protons accelerated by the high-intensity lasers.These high neutron fluxes would make possible not only direct measurements of neutron capture andβ-decay rates related to the r-process of nucleosynthesis of heavy elements,but also such nuclear measurements in a hot plasma environment,which would be beneficial for s-process investigations in astrophysically relevant conditions.This could,in turn,finally allow possible reconciliation of the observed element abundances in stars and those derived from simulations,which at present show large discrepancies.Here,we review a possible pathway to reach unprecedented neutron fluxes using multi-PW lasers,as well as strategies to perform measurements to investigate the r-and s-processes of nucleosynthesis of heavy elements in cold matter,as well as in a hot plasma environment.
基金The authors acknowledge the facility and the technical assistance of the national research infrastructureApollon.The authorswould also like to thank all teams of the laboratories that contributed to the success of the facility,i.e.,all of theCILEXconsortium,whichwas established to buildApollon.Thisworkwas supported by funding fromthe European Research Council(ERC)under the European Unions Horizon 2020 research and innovation program(Grant Agreement No.787539,Project GENESIS),and by Grant No.ANR-17-CE30-0026-Pinnacle from the Agence Nationale de la Recherche.We acknowledge,in the framework of ProjectGENESIS,the support provided by Extreme Light InfrastructureNuclear Physics(ELI-NP)Phase II,a project co-financed by the Romanian Government and the European Union through the European Regional Development Fund,and by the Project No.ELI-RO-2020-23,funded by IFA(Romania)to design,build,and test the neutron detectors used in this project,as well as parts of the OTR diagnostic.JIHT RAS team members are supported by the Ministry of Science and Higher Education of the Russian Federation(State Assignment No.075-00460-21-00)The study reported here was also funded by the Russian Foundation for Basic Research,Project No.20-02-00790.The work of the ENEA team members has been carried out within the framework of the EUROfusionConsortiumand has received funding from the Euratom research and training program 2014–2018 and 2019-2020 under grant agreement No.633053.
文摘We present the results of the first commissioning phase of the short-focal-length area of the Apollon laser facility(located in Saclay,France),which was performed with the first available laser beam(F2),scaled to a nominal power of 1 PW.Under the conditions that were tested,this beam delivered on-target pulses of 10 J average energy and 24 fs duration.Several diagnostics were fielded to assess the performance of the facility.The on-target focal spot and its spatial stability,the temporal intensity profile prior to the main pulse,and the resulting density gradient formed at the irradiated side of solid targets have been thoroughly characterized,with the goal of helping users design future experiments.Emissions of energetic electrons,ions,and electromagnetic radiation were recorded,showing good laser-to-target coupling efficiency and an overall performance comparable to that of similar international facilities.This will be followed in 2022 by a further commissioning stage at the multipetawatt level.
