The article contains an error regarding the electron spectra displayed in Figs.4 and 5 and the data extracted from these spectra.The measurements were made with the SESAME magnetic spectrometer,the working principle o...The article contains an error regarding the electron spectra displayed in Figs.4 and 5 and the data extracted from these spectra.The measurements were made with the SESAME magnetic spectrometer,the working principle of which is recalled in Fig.1.Specifically,a magnetic dipole is used to separate charged particles(electrons in the case of this experiment)depending on their energy,charge and mass.The deflected particles then hit an imaging plate(IP)and deposit energy in its sensitive layer.The kinetic energy of the particles can be evaluated from their impact position on the IP and their number can be inferred from the local energy deposition.展开更多
Pulse pile-up is a problem in nuclear spectroscopy and nuclear reaction studies that occurs when two pulses overlap and distort each other,degrading the quality of energy and timing information.Different methods have ...Pulse pile-up is a problem in nuclear spectroscopy and nuclear reaction studies that occurs when two pulses overlap and distort each other,degrading the quality of energy and timing information.Different methods have been used for pile-up rejection,both digital and analogue,but some pile-up events may contain pulses of interest and need to be reconstructed.The paper proposes a new method for reconstructing pile-up events acquired with a neutron detector array(NEDA)using an one-dimensional convolutional autoencoder(1D-CAE).The datasets for training and testing the 1D-CAE are created from data acquired from the NEDA.The new pile-up signal reconstruction method is evaluated from the point of view of how similar the reconstructed signals are to the original ones.Furthermore,it is analysed considering the result of the neutron-gamma discrimination based on charge comparison,comparing the result obtained from original and reconstructed signals.展开更多
The NEutron Detector Array(NEDA)is designed to be coupled to gamma-ray spectrometers to enhance the sensitivity of the setup by enabling reaction channel selection through counting of the evaporated neutrons.This arti...The NEutron Detector Array(NEDA)is designed to be coupled to gamma-ray spectrometers to enhance the sensitivity of the setup by enabling reaction channel selection through counting of the evaporated neutrons.This article presents the implementation of a double trigger condition system for NEDA,which improves the acquisition of neutrons and reduces the number of gamma rays acquired.Two independent triggers are generated in the double trigger condition system:one based on charge comparison(CC)and the other on time-of-flight(TOF).These triggers can be combined using OR and AND logic,offering four distinct trigger modes.The developed firmware is added to the previous one in the Virtex 6 field programmable gate array(FPGA)present in the system,which also includes signal processing,baseline correction,and various trigger logic blocks.The performance of the trigger system is evaluated using data from the E703 experiment performed at GANIL.The four trigger modes are applied to the same data,and a subsequent offline analysis is performed.It is shown that most of the detected neutrons are preserved with the AND mode,and the total number of gamma rays is significantly reduced.Compared with the CC trigger mode,the OR trigger mode allows increasing the selection of neutrons.In addition,it is demonstrated that if the OR mode is selected,the online CC trigger threshold can be raised without losing neutrons.展开更多
Previous experiments with organo-metallic compounds like ferrocene,nickelocene and magnesocene showed that a pure spectrum must be obtained on the residual gas mass analyser before running successfully on the ion sour...Previous experiments with organo-metallic compounds like ferrocene,nickelocene and magnesocene showed that a pure spectrum must be obtained on the residual gas mass analyser before running successfully on the ion source.In collaboration with the chemistry department of the University of Caen,LCMT-ENSI Caen,the synthesis of these metallocene compounds has been studied to provide enriched isotopic compounds to GANIL’s users.The chemical transformation yields were 90%,80% and 43%,respectively.Vanadocene, chromocene,colbatocene and ruthenocene compounds have first been studied with a gas mass analyser and then successfully tested on the ECR 4M ion source at GANIL.Some 15eμA of ^(51)V^(11+),20eμA of ^(52)Cr^(11+), 22eμA of 59Co^(11+),and 17eμA of ^(102)Ru^(11+) were achieved.The comparison between the results obtained on the gas mass analyser and the ion beams provided by the source has allowed us to validate this method of determining whether or not an organo-metallic compound could be a candidate for running on our ECR ion source.As the ECR ion sources are tuned and used alternately on the GANIL injectors,the available time for the tests is rare,so this method could be an alternative for the validation of new compounds.展开更多
Synthesis of superheavy elements beyond oganesson is facing new challenges as new target–projectile combinations are necessary. Guidance from models is thus expected for future experiments. However, hindered fusion m...Synthesis of superheavy elements beyond oganesson is facing new challenges as new target–projectile combinations are necessary. Guidance from models is thus expected for future experiments. However, hindered fusion models are not well established and predictions in the fission barriers span few MeVs. Consequently, predictions are not reliable. Strategies to constrain both fusion hindrance and fission barriers are necessary to improve the predictive power of the models. But, there is no hope to get an accuracy better than one order of magnitude in fusion–evaporation reactions leading to superheavy elements synthesis.展开更多
The high-energy petawatt PETAL laser system was commissioned at CEA’s Laser M´egajoule facility during the 2017–2018 period.This paper reports in detail on the first experimental results obtained at PETAL on en...The high-energy petawatt PETAL laser system was commissioned at CEA’s Laser M´egajoule facility during the 2017–2018 period.This paper reports in detail on the first experimental results obtained at PETAL on energetic particle and photon generation from solid foil targets,with special emphasis on proton acceleration.Despite a moderately relativistic(<1019 W/cm^(2))laser intensity,proton energies as high as 51 MeV have been measured significantly above those expected from preliminary numerical simulations using idealized interaction conditions.Multidimensional hydrodynamic and kinetic simulations,taking into account the actual laser parameters,show the importance of the energetic electron production in the extended low-density preplasma created by the laser pedestal.This hot-electron generation occurs through two main pathways:(i)stimulated backscattering of the incoming laser light,triggering stochastic electron heating in the resulting counterpropagating laser beams;(ii)laser filamentation,leading to local intensifications of the laser field and plasma channeling,both of which tend to boost the electron acceleration.Moreover,owing to the large(∼100μm)waist and picosecond duration of the PETAL beam,the hot electrons can sustain a high electrostatic field at the target rear side for an extended period,thus enabling efficient target normal sheath acceleration of the rear-side protons.The particle distributions predicted by our numerical simulations are consistent with the measurements.展开更多
The collective flow for <sup>64</sup>Zn+<sup>27</sup>Al system is measured at intermediate energyby using a 4π multidetector array in conjunction with an array of Si telescopes.Theevents have ...The collective flow for <sup>64</sup>Zn+<sup>27</sup>Al system is measured at intermediate energyby using a 4π multidetector array in conjunction with an array of Si telescopes.Theevents have been sorted versus the impact parameter by means of global variables.Three methods of reaction plane determination are compared:sphericity tensor method,transverse momentum analysis,and azimuthal correlation method.For this system,thetransverse momentum analysis method is the best one.展开更多
We investigate the theoretical description of nuclei at drip-lines.For this,the Gamow shell model has been developed to study the properties of weakly bound and resonance nuclei.
In this white paper,we present the potential of the enhanced X-ray timing and polarimetry(eXTP)mission to constrain the equation of state of dense matter in neutron stars,exploring regimes not directly accessible to t...In this white paper,we present the potential of the enhanced X-ray timing and polarimetry(eXTP)mission to constrain the equation of state of dense matter in neutron stars,exploring regimes not directly accessible to terrestrial experiments.By observing a diverse population of neutron stars—including isolated objects,X-ray bursters,and accreting systems—eXTP’s unique combination of timing,spectroscopy,and polarimetry enables high-precision measurements of compactness,spin,surface temperature,polarimetric signals,and timing irregularity.These multifaceted observations,combined with advances in theoretical modeling,pave the way toward a comprehensive description of the properties and phases of dense matter from the crust to the core of neutron stars.Under development by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Sciences,the eXTP mission is planned to be launched in early 2030.展开更多
The fusion hindrance,which is also denominated by the term extra-push,is studied on mass-symmetric systems by the use of the liquid drop model with the two-center parameterization.Following the idea that the fusion hi...The fusion hindrance,which is also denominated by the term extra-push,is studied on mass-symmetric systems by the use of the liquid drop model with the two-center parameterization.Following the idea that the fusion hindrance exists only if the liquid drop barrier(saddle point) is located at the inner side of the contact point after overcoming the outer Coulomb barrier,the reactions in which two barriers are overlapped with each other are determined.It is shown that there are many systems where the fusion hindrance does not exist for the atomic number of projectile or target nucleus Z 43,while for Z> 43,all of the mass-symmetric reactions are fusion-hindered.展开更多
This paper is a short revisit to Kuo-Brown effective interaction derived from the Hamada-Johnston nucleon-nucleon potential, done by Gerry Brown and Tom Kuo. This effective interaction, derived in year 1966, is the fi...This paper is a short revisit to Kuo-Brown effective interaction derived from the Hamada-Johnston nucleon-nucleon potential, done by Gerry Brown and Tom Kuo. This effective interaction, derived in year 1966, is the first attempt to describe nuclear structure properties from the free nucleon-nucleon potential. Nowadays much progress has been achieved for the effective interactions in shell model. We would compare the effective interactions obtained in the 1966 paper with up-to-date shell-model interactions in sd-shell and pf-shell model space. Recent knowledge of effective interactions on nuclear structure, can also be traced in the KuoBrown effective interaction, i.e., the universal roles of central and tensor forces, which reminds us that such discovery should be noticed much earlier.展开更多
ECRIS’s dedicated to radioactive ion production must be as efficient as those used for production of stable elements,but in addition they are subject to more specific constraints such as radiation hardness, short ato...ECRIS’s dedicated to radioactive ion production must be as efficient as those used for production of stable elements,but in addition they are subject to more specific constraints such as radiation hardness, short atom-to-ion transformation time,beam purity and low cost.Up to now,different target/ion-source systems(TISSs)have been designed,using singly-charged ECRISs,multi-charged ion sources or an association of singly-to-multi-charged ECRISs.The main goals,constraints and advantages of different existing ECR setups will be compared before a more detailed description is given of the one designed for the SPIRALⅡproject and its future improvements.展开更多
The level structure in neutron-deficient nucleus 91Ru was investigated via the 58Ni(36Ar,2 plnγ)Ru reaction at a beam energy of 111 MeV.Charged particles,neutrons,and y-rays were emitted in this reaction and detected...The level structure in neutron-deficient nucleus 91Ru was investigated via the 58Ni(36Ar,2 plnγ)Ru reaction at a beam energy of 111 MeV.Charged particles,neutrons,and y-rays were emitted in this reaction and detected by the DIAMANT CsI ball,Neutron Wall,and the EXOGAM Ge clover array,respectively.In addition to the previously reported levels in 91Ru,new low-to-medium spin states were observed.Angular correlation and linear polarization measurements were performed to unambiguously determine spins and parities of the excited states in 91 Ru.The low-spin states of 91 Ru exhibit a scheme of multi-quasiparticle excitations,which is very similar to that of the neighboring N=47 isotone.These excitations have been interpreted in terms of the shell model.The calculations performed in the configuration space(p3/2,f5/2,p1/2,g9/2)reproduce the experimental excitation energies reasonably well,supporting the interpretation of the newly assigned positive-parity states in terms of the three quasiparticle configurationsπ(g9/2)^-2v(g9/2^-1 and v(g9/2)^-3.展开更多
At the moment,a 70MeV cyclotron is under construction by the IBA company.This cyclotron will be able to accelerate H^- beam from a multicusp source and with a beam intensity in the range of 10mA at the source extracti...At the moment,a 70MeV cyclotron is under construction by the IBA company.This cyclotron will be able to accelerate H^- beam from a multicusp source and with a beam intensity in the range of 10mA at the source extraction.A He^(1+2+) beam is also required.This beam will be produced by a PANTECHNIK ECR ion source(SUPERNANOGAN)with an extracted current of 1 to 2mA.In this paper the studies and design of the two sources with a common axial injection in the cyclotron are described.展开更多
文摘The article contains an error regarding the electron spectra displayed in Figs.4 and 5 and the data extracted from these spectra.The measurements were made with the SESAME magnetic spectrometer,the working principle of which is recalled in Fig.1.Specifically,a magnetic dipole is used to separate charged particles(electrons in the case of this experiment)depending on their energy,charge and mass.The deflected particles then hit an imaging plate(IP)and deposit energy in its sensitive layer.The kinetic energy of the particles can be evaluated from their impact position on the IP and their number can be inferred from the local energy deposition.
基金partially supported by MICIU MCIN/AEI/10.13039/501100011033Spain with grant PID2020-118265GB-C42,-C44,PRTR-C17.I01+1 种基金Generalitat Valenciana,Spain with grant CIPROM/2022/54,ASFAE/2022/031,CIAPOS/2021/114the EU NextGenerationEU,ESF funds,and the National Science Centre (NCN),Poland (grant No.2020/39/D/ST2/00466)
文摘Pulse pile-up is a problem in nuclear spectroscopy and nuclear reaction studies that occurs when two pulses overlap and distort each other,degrading the quality of energy and timing information.Different methods have been used for pile-up rejection,both digital and analogue,but some pile-up events may contain pulses of interest and need to be reconstructed.The paper proposes a new method for reconstructing pile-up events acquired with a neutron detector array(NEDA)using an one-dimensional convolutional autoencoder(1D-CAE).The datasets for training and testing the 1D-CAE are created from data acquired from the NEDA.The new pile-up signal reconstruction method is evaluated from the point of view of how similar the reconstructed signals are to the original ones.Furthermore,it is analysed considering the result of the neutron-gamma discrimination based on charge comparison,comparing the result obtained from original and reconstructed signals.
基金supported by MICIU MCIN/AEI/10.13039/501100011033Spain with Grant PID2020-118265GB-C42,-C44,PRTR-C17.I01Generalitat Valenciana,Spain with Grant CIPROM/2022/54,ASFAE/2022/031,CIAPOS/2021/114 and by the EU NextGenerationEU,ESF funds.This work was also supported by the National Science Centre(NCN),Poland(Grant No.2020/39/D/ST2/00466).
文摘The NEutron Detector Array(NEDA)is designed to be coupled to gamma-ray spectrometers to enhance the sensitivity of the setup by enabling reaction channel selection through counting of the evaporated neutrons.This article presents the implementation of a double trigger condition system for NEDA,which improves the acquisition of neutrons and reduces the number of gamma rays acquired.Two independent triggers are generated in the double trigger condition system:one based on charge comparison(CC)and the other on time-of-flight(TOF).These triggers can be combined using OR and AND logic,offering four distinct trigger modes.The developed firmware is added to the previous one in the Virtex 6 field programmable gate array(FPGA)present in the system,which also includes signal processing,baseline correction,and various trigger logic blocks.The performance of the trigger system is evaluated using data from the E703 experiment performed at GANIL.The four trigger modes are applied to the same data,and a subsequent offline analysis is performed.It is shown that most of the detected neutrons are preserved with the AND mode,and the total number of gamma rays is significantly reduced.Compared with the CC trigger mode,the OR trigger mode allows increasing the selection of neutrons.In addition,it is demonstrated that if the OR mode is selected,the online CC trigger threshold can be raised without losing neutrons.
文摘Previous experiments with organo-metallic compounds like ferrocene,nickelocene and magnesocene showed that a pure spectrum must be obtained on the residual gas mass analyser before running successfully on the ion source.In collaboration with the chemistry department of the University of Caen,LCMT-ENSI Caen,the synthesis of these metallocene compounds has been studied to provide enriched isotopic compounds to GANIL’s users.The chemical transformation yields were 90%,80% and 43%,respectively.Vanadocene, chromocene,colbatocene and ruthenocene compounds have first been studied with a gas mass analyser and then successfully tested on the ECR 4M ion source at GANIL.Some 15eμA of ^(51)V^(11+),20eμA of ^(52)Cr^(11+), 22eμA of 59Co^(11+),and 17eμA of ^(102)Ru^(11+) were achieved.The comparison between the results obtained on the gas mass analyser and the ion beams provided by the source has allowed us to validate this method of determining whether or not an organo-metallic compound could be a candidate for running on our ECR ion source.As the ECR ion sources are tuned and used alternately on the GANIL injectors,the available time for the tests is rare,so this method could be an alternative for the validation of new compounds.
基金supported in part by the NSF of China(Nos.11747312,U1732138,11790325,11790323)the Joint International Laboratory between France and Japan(LIA FJNSP)
文摘Synthesis of superheavy elements beyond oganesson is facing new challenges as new target–projectile combinations are necessary. Guidance from models is thus expected for future experiments. However, hindered fusion models are not well established and predictions in the fission barriers span few MeVs. Consequently, predictions are not reliable. Strategies to constrain both fusion hindrance and fission barriers are necessary to improve the predictive power of the models. But, there is no hope to get an accuracy better than one order of magnitude in fusion–evaporation reactions leading to superheavy elements synthesis.
基金funding from the Conseil Regional d’Aquitaine,the French Ministry of Research,and the European Unionfunded by the French Agence Nationale de la Recherche under Grant No.ANR-10-EQPX-42-01+1 种基金funded by the LabEx LAPHIA of the University of Bordeaux under Grant No.ANR-10-IDEX-03-02supported by Association Lasers et Plasmas and by the CEA。
文摘The high-energy petawatt PETAL laser system was commissioned at CEA’s Laser M´egajoule facility during the 2017–2018 period.This paper reports in detail on the first experimental results obtained at PETAL on energetic particle and photon generation from solid foil targets,with special emphasis on proton acceleration.Despite a moderately relativistic(<1019 W/cm^(2))laser intensity,proton energies as high as 51 MeV have been measured significantly above those expected from preliminary numerical simulations using idealized interaction conditions.Multidimensional hydrodynamic and kinetic simulations,taking into account the actual laser parameters,show the importance of the energetic electron production in the extended low-density preplasma created by the laser pedestal.This hot-electron generation occurs through two main pathways:(i)stimulated backscattering of the incoming laser light,triggering stochastic electron heating in the resulting counterpropagating laser beams;(ii)laser filamentation,leading to local intensifications of the laser field and plasma channeling,both of which tend to boost the electron acceleration.Moreover,owing to the large(∼100μm)waist and picosecond duration of the PETAL beam,the hot electrons can sustain a high electrostatic field at the target rear side for an extended period,thus enabling efficient target normal sheath acceleration of the rear-side protons.The particle distributions predicted by our numerical simulations are consistent with the measurements.
文摘The collective flow for <sup>64</sup>Zn+<sup>27</sup>Al system is measured at intermediate energyby using a 4π multidetector array in conjunction with an array of Si telescopes.Theevents have been sorted versus the impact parameter by means of global variables.Three methods of reaction plane determination are compared:sphericity tensor method,transverse momentum analysis,and azimuthal correlation method.For this system,thetransverse momentum analysis method is the best one.
文摘We investigate the theoretical description of nuclei at drip-lines.For this,the Gamow shell model has been developed to study the properties of weakly bound and resonance nuclei.
基金supported by China’s Space Origins Exploration Programsupported by the National Natural Science Foundation of China (Grant No.12273028)+36 种基金support from ERC Consolidator (Grant No.865768) AEONSsupport from NWO grant ENW-XL OCENW.XL21.XL21.038the support of the CNESsupported by the National Natural Science Foundation of China (Grant No.12333007)the International Partnership Program of Chinese Academy of Sciences (Grant No.113111KYSB20190020)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDA15020100)supported by the China National Postdoctoral Program for Innovation Talents (Grant No.BX20240223)the China Postdoctoral Science Foundation Funded Project (Grant No.2024M761948)support from a Ramon y Cajal fellowship (Grant No.RYC2021-032718-I) financed by MCIN/AEI/10.13039/501100011033 and the European Union Next Generation EU/PRTRsupported by the Natural Science Foundation of Xinjiang Uygur Autonomous Region (Grant No.2023D01E20)the National SKA Program of China (Grant No.2020SKA0120300)supported by the National Natural Science Foundation of China (Grant Nos.12033001,and 12473039)supported by Zhejiang Provincial Natural Science Foundation of China (Grant No.LQ24A030002)supported by the National Natural Science Foundation of China (Grant No.12003009)supported by the National SKA Program of China (Grant No.2020SKA0120200)the National Natural Science Foundation of China (Grant No.12041303)supported by the National Natural Science Foundation of China (Grant No.1227303)supported by the National SKA Program of China (Grant No.2020SKA0120300)the Beijing Natural Science Foundation (Grant No.1242018)the Max Planck Partner Group Program funded by the Max Planck Societysupported by JSPS KAKENHI (the Japan Society for the Promotion of Science,Grantsin-Aid for Scientific Research) (Grant Nos.23K19056,and 25K17403)supported by the National Natural Science Foundation of China (Grant No.12175109)support from FCT (Fundacao para a Ciência e a Tecnologia,I.P.,Portugal) (Grant Nos.UIDB/04564/2020,and 2022.06460.PTDC)supported from the program Unidad de Excelencia María de Maeztu CEX2020-001058-Mfrom the project PID2022-139427NB-I00 financed by the Spanish MCIN/AEI/10.13039/501100011033/FEDER,UE (FSE+)by the CRC-TR 211 “Strong-interaction matter under extreme conditions” -project Nr.315477589-TRR 211support from grant PID2021-124581OB-I0,PID2024-155316NB-I00,and 2021SGR00426supported by the National Natural Science Foundation of China (Grant No.12122513)supported in part by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant No.101020842)by the Deutsche Forschungsgemeinschaft (DFG,German Research Foundation)-Project-ID 279384907-SFB 1245support from the ERC Consolidator (Grant No.101002352) (LOVENEST)supported by the European Research Council (ERC) via the Consolidator Grant “MAGNESIA” (Grant No.817661)the Proof of Concept “Deep Space Pulse” (Grant No.101189496)the Catalan grant SGR2021-01269the Spanish grant ID2023-153099NA-I00the program Unidad de Excelencia Maria de Maeztu CEX2020-001058-Msupported by the Research Council of Finland (Grant No.354533).
文摘In this white paper,we present the potential of the enhanced X-ray timing and polarimetry(eXTP)mission to constrain the equation of state of dense matter in neutron stars,exploring regimes not directly accessible to terrestrial experiments.By observing a diverse population of neutron stars—including isolated objects,X-ray bursters,and accreting systems—eXTP’s unique combination of timing,spectroscopy,and polarimetry enables high-precision measurements of compactness,spin,surface temperature,polarimetric signals,and timing irregularity.These multifaceted observations,combined with advances in theoretical modeling,pave the way toward a comprehensive description of the properties and phases of dense matter from the crust to the core of neutron stars.Under development by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Sciences,the eXTP mission is planned to be launched in early 2030.
基金Supported by the National Natural Science Foundation of China (Grant No.10675046)the Key Project of the Ministry of Education of China(Grant No.209053)the JSPS (Grant No.18540268)
文摘The fusion hindrance,which is also denominated by the term extra-push,is studied on mass-symmetric systems by the use of the liquid drop model with the two-center parameterization.Following the idea that the fusion hindrance exists only if the liquid drop barrier(saddle point) is located at the inner side of the contact point after overcoming the outer Coulomb barrier,the reactions in which two barriers are overlapped with each other are determined.It is shown that there are many systems where the fusion hindrance does not exist for the atomic number of projectile or target nucleus Z 43,while for Z> 43,all of the mass-symmetric reactions are fusion-hindered.
基金supported by the National Natural Science Foundation of China(Grant Nos.11275067 and 11447109)the support from the Helmholtz Association(HGF)through the Nuclear Astrophysics Virtual Institute(VH-VI-417)
文摘This paper is a short revisit to Kuo-Brown effective interaction derived from the Hamada-Johnston nucleon-nucleon potential, done by Gerry Brown and Tom Kuo. This effective interaction, derived in year 1966, is the first attempt to describe nuclear structure properties from the free nucleon-nucleon potential. Nowadays much progress has been achieved for the effective interactions in shell model. We would compare the effective interactions obtained in the 1966 paper with up-to-date shell-model interactions in sd-shell and pf-shell model space. Recent knowledge of effective interactions on nuclear structure, can also be traced in the KuoBrown effective interaction, i.e., the universal roles of central and tensor forces, which reminds us that such discovery should be noticed much earlier.
文摘ECRIS’s dedicated to radioactive ion production must be as efficient as those used for production of stable elements,but in addition they are subject to more specific constraints such as radiation hardness, short atom-to-ion transformation time,beam purity and low cost.Up to now,different target/ion-source systems(TISSs)have been designed,using singly-charged ECRISs,multi-charged ion sources or an association of singly-to-multi-charged ECRISs.The main goals,constraints and advantages of different existing ECR setups will be compared before a more detailed description is given of the one designed for the SPIRALⅡproject and its future improvements.
基金Supported by National Natural Science Foundation of China(U1632137)
文摘The level structure in neutron-deficient nucleus 91Ru was investigated via the 58Ni(36Ar,2 plnγ)Ru reaction at a beam energy of 111 MeV.Charged particles,neutrons,and y-rays were emitted in this reaction and detected by the DIAMANT CsI ball,Neutron Wall,and the EXOGAM Ge clover array,respectively.In addition to the previously reported levels in 91Ru,new low-to-medium spin states were observed.Angular correlation and linear polarization measurements were performed to unambiguously determine spins and parities of the excited states in 91 Ru.The low-spin states of 91 Ru exhibit a scheme of multi-quasiparticle excitations,which is very similar to that of the neighboring N=47 isotone.These excitations have been interpreted in terms of the shell model.The calculations performed in the configuration space(p3/2,f5/2,p1/2,g9/2)reproduce the experimental excitation energies reasonably well,supporting the interpretation of the newly assigned positive-parity states in terms of the three quasiparticle configurationsπ(g9/2)^-2v(g9/2^-1 and v(g9/2)^-3.
文摘At the moment,a 70MeV cyclotron is under construction by the IBA company.This cyclotron will be able to accelerate H^- beam from a multicusp source and with a beam intensity in the range of 10mA at the source extraction.A He^(1+2+) beam is also required.This beam will be produced by a PANTECHNIK ECR ion source(SUPERNANOGAN)with an extracted current of 1 to 2mA.In this paper the studies and design of the two sources with a common axial injection in the cyclotron are described.