The measurement of the bound-state decay of^(205)Tl at the Experimental Storage Ring(ESR)at GSI,Darmstadt,has recently been reported,with substantial impact on the use of^(205)Pb as an early Solar System chronometer a...The measurement of the bound-state decay of^(205)Tl at the Experimental Storage Ring(ESR)at GSI,Darmstadt,has recently been reported,with substantial impact on the use of^(205)Pb as an early Solar System chronometer and on the low-energy measurement of the solar neutrino spectrum via the LOREX project.Owing to the technical challenges in producing a high-purity^(205)T^(l81+)secondary beam,a robust statistical method was developed to estimate the variation in the contaminant^(205)Pb^(81+)produced in the fragmentation reaction,which was subsequently transmitted and stored in the ESR.Here,we show that Bayesian and Monte Carlo methods produce comparable estimates for the contaminant variation,each with unique advantages and challenges given the complex statistical problems for this experiment.We recommend the adoption of such methods in future experiments that exhibit unknown statistical fluctuations.展开更多
Precision mass measurements of neutron-deficient 152Sm projectile fragments were conducted in 2005 at theFRS-ESR facility at GSI Helmholtz centre[1, 2], employing the time-resolved Schottky Mass Spectrometry[3]. A new...Precision mass measurements of neutron-deficient 152Sm projectile fragments were conducted in 2005 at theFRS-ESR facility at GSI Helmholtz centre[1, 2], employing the time-resolved Schottky Mass Spectrometry[3]. A newmass evaluation method has been developed in the data analysis. The systematic error in the mass determinationwas significantly reduced with the new method[4].Exotic nuclei, produced by projectile fragmentation of a 615 AMeV 152Sm primary beam in a 4.009 g/cm2beryllium target, were transmitted and B-separated by the fragment separator FRS and then injected and storedin the experimental storage ring ESR. In ESR the electron-cooling process was continuously applied to the storedions. To first order approximation, the revolution-frequencies (f) of the stored ions in the ESR are related to theirvelocities (v) and mass-to-charge ratios (m=q) of the ions in rest frame:展开更多
An experiment aimed to investigate the two-proton(2p) decay of the previously unknown nucleus ^(30)Ar was performed at GSI. By tracking the decay products in-flight with silicon micro-strip detectors, the 2p decays of...An experiment aimed to investigate the two-proton(2p) decay of the previously unknown nucleus ^(30)Ar was performed at GSI. By tracking the decay products in-flight with silicon micro-strip detectors, the 2p decays of ^(30)Ar were observed for the first time. For the calibration purpose, 2p decays of ^(19)Mg were also remeasured by tracking the coincident ^(17)Ne+p+p trajectories. By comparing the measured angular p-17 Ne correlations with those obtained from the corresponding Monte Carlo simulations,the simultaneous 2p decay of ^(19)Mg ground state and the sequential 2p emission of several known excited states of ^(19)Mg were confirmed. One new excited state in ^(19)Mg and two new excited states in ^(18)Na were observed.展开更多
基金funding from the European Research Council(ERC)under the European Union's Horizon 2020 research and innovation programme(Grant Agreement No.682841"ASTRUm"and No.654002"ENSAR2")The research of G.Leckenby,I.Dillmann,and C.Griffin was funded by the Canadian Natural Sciences and Engineering Research Council(NSERC)via the grant SAPIN-2019-00030+1 种基金J.Glorius,M.S.Sanjari,Yu.A.Litvinov and C.Brandau acknowledge support by the State of Hesse within the Research Cluster ELEMENTS(Project ID 500/10.006)E.Menz and Yu.A.Litvinov acknowledge support by the project"NRW-FAIR",a part of the programme"Netzwerke 2021",an initiative of the Ministry of Culture and Science of the State of North Rhine-Westphalia.R.Gernhäuser acknowledges support by the Excellence Cluster ORIGINS from the German Research Foundation DFG(Excellence Strategy EXC-2094-390783311)。
文摘The measurement of the bound-state decay of^(205)Tl at the Experimental Storage Ring(ESR)at GSI,Darmstadt,has recently been reported,with substantial impact on the use of^(205)Pb as an early Solar System chronometer and on the low-energy measurement of the solar neutrino spectrum via the LOREX project.Owing to the technical challenges in producing a high-purity^(205)T^(l81+)secondary beam,a robust statistical method was developed to estimate the variation in the contaminant^(205)Pb^(81+)produced in the fragmentation reaction,which was subsequently transmitted and stored in the ESR.Here,we show that Bayesian and Monte Carlo methods produce comparable estimates for the contaminant variation,each with unique advantages and challenges given the complex statistical problems for this experiment.We recommend the adoption of such methods in future experiments that exhibit unknown statistical fluctuations.
文摘Precision mass measurements of neutron-deficient 152Sm projectile fragments were conducted in 2005 at theFRS-ESR facility at GSI Helmholtz centre[1, 2], employing the time-resolved Schottky Mass Spectrometry[3]. A newmass evaluation method has been developed in the data analysis. The systematic error in the mass determinationwas significantly reduced with the new method[4].Exotic nuclei, produced by projectile fragmentation of a 615 AMeV 152Sm primary beam in a 4.009 g/cm2beryllium target, were transmitted and B-separated by the fragment separator FRS and then injected and storedin the experimental storage ring ESR. In ESR the electron-cooling process was continuously applied to the storedions. To first order approximation, the revolution-frequencies (f) of the stored ions in the ESR are related to theirvelocities (v) and mass-to-charge ratios (m=q) of the ions in rest frame:
基金Helmholtz International Center for FAIR(HIC for FAIR)Helmholtz Association(IK-RU-002)+5 种基金Russian Ministry of Education and Science(NSh-932.2014.2)Russian Foundation for Basic Research(14-02-00090-a)Polish National Science Center(UMO-2011/01/B/ST2/01943)Polish Ministry of Science and Higher Education(0079/DIA/2014/43,Grant Diamentowy)Helmholtz-CAS Joint Research Group(HCJRG-108)FPA2009-08848 contract(MICINN,Spain)
文摘An experiment aimed to investigate the two-proton(2p) decay of the previously unknown nucleus ^(30)Ar was performed at GSI. By tracking the decay products in-flight with silicon micro-strip detectors, the 2p decays of ^(30)Ar were observed for the first time. For the calibration purpose, 2p decays of ^(19)Mg were also remeasured by tracking the coincident ^(17)Ne+p+p trajectories. By comparing the measured angular p-17 Ne correlations with those obtained from the corresponding Monte Carlo simulations,the simultaneous 2p decay of ^(19)Mg ground state and the sequential 2p emission of several known excited states of ^(19)Mg were confirmed. One new excited state in ^(19)Mg and two new excited states in ^(18)Na were observed.
