Background and Aims: Mesocentrotus nudus is commercially harvested from shallow rocky bottoms in northern Japan. The gonads are targeted as an edible product. The objective of this study was to identify odor-active vo...Background and Aims: Mesocentrotus nudus is commercially harvested from shallow rocky bottoms in northern Japan. The gonads are targeted as an edible product. The objective of this study was to identify odor-active volatile organic compounds (VOCs) from the gonads of adult M. nudus collected at a fishing ground in Miyagi Prefecture, Tohoku, Japan. Methods and Results: Gas chromatography-mass spectrometry analysis and gas chromatography-sniffing techniques identified 42 compounds categorized as alcohols, aldehydes, aromatic hydrocarbons, esters, halomethanes, hydrocarbons, ketones, sulfur-containing compounds, and nitrogen-containing compounds. GC-sniffing analysis characterized four compounds with preferable odors of sea urchin gonads;limonene, propyl acetate, acetone, dibromochloromethane. On the other hand, the analysis characterized three compounds with unpreferable odors;methyl mercaptane, dimethyl sulfide, and s-methyl thioacetate. Several VOCs from the gonads were derived from seaweeds, terrestrial plants, and fish flesh as food because M. nudus is omnivorous. Conclusion: This is the first study to identify VOCs from edible sea urchin gonads in the wild in Japan. These VOC data comprise a typical standard in order to evaluate a higher quality of sea urchin gonads.展开更多
In the collaboration of RI Applications Team from RIKEN (Japan) and the Nuclear Chemistry Group from IMP (China), the short-lived Re carbonyl complexes were synthesized and investigated. As the lighter homologs of sup...In the collaboration of RI Applications Team from RIKEN (Japan) and the Nuclear Chemistry Group from IMP (China), the short-lived Re carbonyl complexes were synthesized and investigated. As the lighter homologs of superheavy element Bh, Re belongs to period 6, group 7 of the periodic table. Short-lived Re isotopes with half-lives of several minutes were produced in the reactions of natGd(23Na7+, xn) 172?177Re at Nishina center of RIKEN.展开更多
After the volatile Re carbonyl complexes were synthesized and their volatility was studied we performed another experiment to measure their chemical yields when He were used as the carrier gas. The same experimental s...After the volatile Re carbonyl complexes were synthesized and their volatility was studied we performed another experiment to measure their chemical yields when He were used as the carrier gas. The same experimental setups were used except the low temperature isothermal chromatography device[1]. The natGd2O3 target and 23Na7+ion beam were used to produce short-lived Re isotopes, and the Gas-filled Recoil Ion Separator (GARIS) was employed to separate the evaporation residues[2]. High purity He gas and CO gas were used as the mixed gas. The depth of recoil chamber was 100 mm because of the long stop range in He gas, and the gas pressure was around 80 kpa. The total gas flow rate was 1 L/min.展开更多
The production of ^(99)Mo is currently relying on nuclear reactors,however,most of the reactors are aged and most of them are about to be closed in the next decade.In recent years,other alternative routes to produce t...The production of ^(99)Mo is currently relying on nuclear reactors,however,most of the reactors are aged and most of them are about to be closed in the next decade.In recent years,other alternative routes to produce the radioisotope currently attract much attention and are discussed.展开更多
The effects of the tensor force on the and decay nuclear matrix elements(NMEs)of,,,and are studied using the Hartree-Fock-Bogoliubov(HFB)plus proton-neutron quasi-particle random phase approximation(pnQRPA)model based...The effects of the tensor force on the and decay nuclear matrix elements(NMEs)of,,,and are studied using the Hartree-Fock-Bogoliubov(HFB)plus proton-neutron quasi-particle random phase approximation(pnQRPA)model based on the Skyrme energy density functional.We include the full spectra of intermediate states with up to the energy cutoff E=60 MeV,which is sufficient for convergence of NME calculations.The isovector(IV)pairing and tensor interactions are considered in both HFB and QRPA calculations,while the isoscalar(IS)pairing interaction is included only in QRPA calculations.We found that the tensor force shifts Gamow-Teller(GT)transition strengths substantially to low-energy regions and enhances the decay NME.The inclusion of tensor force enhances the NME by approximately 13%for and and 30%for and,for a fixed IS pairing strength.We found that the intermediate 2-state makes an important contribution to the NME,which is slightly enhanced by the inclusion of the tensor force.We also found that the contribution of the state makes important differences through the inclusion of the tensor force,which enhances the contribution largely.However when the IS pairing strength is increased,the contributions from 1+states are rapidly reduced to be very small,resulting in even negative contributions.Thus,tensor and IS pairing effects cancel each other,making the net effect on the NME relatively small.Due to this cancellation,if the IS pairing strength is optimized separately for cases with and without the tensor interaction to reproduce the experimental NME,the consequent NME with the tensor interaction is close to that without the tensor interaction within a 10%difference.展开更多
Hypernuclei,nuclei containing one or more hyperons,serve as unique laboratories for probing the non-perturbative quantum chromodynamics(QCD).Recent progress in hypernuclear physics,driven by advanced experimental tech...Hypernuclei,nuclei containing one or more hyperons,serve as unique laboratories for probing the non-perturbative quantum chromodynamics(QCD).Recent progress in hypernuclear physics,driven by advanced experimental techniques and theoretical innovations,is briefly reviewed with a focus on key findings and unresolved challenges,such as the precise determination of the hypertriton binding energy,investigations of charge symmetry breaking in mirror hypernuclei,and the search for exotic systems,including the neutral nnΛstate.Experimental breakthroughs,including invariant-mass analyses and femtoscopy studies in heavy-ion collisions,as well as high-resolutionγ-spectroscopy,have enabled precise studies of light hypernuclei and offered critical insights into the hyperon–nucleon interaction.Theoretical progress,including ab initio calculations based on chiral effective field theory and lattice QCD,has further enhanced our understanding of hyperon–nucleon and hyperon–hyperon interactions.展开更多
We have investigated the internal structure of the open-and hidden-charmed(DD^(*)/DD^(*))molecules in the unified framework.We first fit the experimental lineshape of the Tt state and extract the DD^(*)interaction,fro...We have investigated the internal structure of the open-and hidden-charmed(DD^(*)/DD^(*))molecules in the unified framework.We first fit the experimental lineshape of the Tt state and extract the DD^(*)interaction,from which the T is assumed to arise solely.Then we obtain the DD^(*)interaction by charge conjugation.Our results show that the DD*interaction is attractive but insufficient to form X(3872)as a bound state.Instead,its formation requires the crucial involvement of the coupled channel effect between the DD^(*)and cc components,although the cc accounts for approximately 1%only.Besides X(3872),we have obtained a higher-energy state around 3957.9 MeV with a width of 16.7 MeV,which may be a potential candidate for the X(3940).In J^(PC)=1^(+-)sector,we have found two states related to the iso-scalar X(3872)and h_(c)(2P),respectively.Our combined study provides valuable insights into the nature of these DD^(+)/DD^(+)exotic states.展开更多
Research activities of nuclear physics at Radioactive Isotope Beam Factory over 10 years are reviewed and future directions are also discussed. Conceptual ideas in designing the facility as well as experimental device...Research activities of nuclear physics at Radioactive Isotope Beam Factory over 10 years are reviewed and future directions are also discussed. Conceptual ideas in designing the facility as well as experimental devices are introduced. Special emphasis is given to highlighted results obtained at RIBF.展开更多
Hypernuclear physics has become very exciting owing to new epoch-making experimental data. Recent progress in theoretical and experimental studies of hypernuclei and future developments in this field are discussed.
We develop a covariant kinetic theory for massive fermions in a curved spacetime and an external electromagnetic field based on quantum field theory.We derive four coupled semi-classical kinetic equations accurate to ...We develop a covariant kinetic theory for massive fermions in a curved spacetime and an external electromagnetic field based on quantum field theory.We derive four coupled semi-classical kinetic equations accurate to O(ℏ),which describe the transports of particle number and spin degrees of freedom.The relationship with chiral kinetic theory is discussed.As an application,we study spin polarization in the presence of finite Riemann curvature and an electromagnetic field in both local and global equilibrium states.展开更多
文摘Background and Aims: Mesocentrotus nudus is commercially harvested from shallow rocky bottoms in northern Japan. The gonads are targeted as an edible product. The objective of this study was to identify odor-active volatile organic compounds (VOCs) from the gonads of adult M. nudus collected at a fishing ground in Miyagi Prefecture, Tohoku, Japan. Methods and Results: Gas chromatography-mass spectrometry analysis and gas chromatography-sniffing techniques identified 42 compounds categorized as alcohols, aldehydes, aromatic hydrocarbons, esters, halomethanes, hydrocarbons, ketones, sulfur-containing compounds, and nitrogen-containing compounds. GC-sniffing analysis characterized four compounds with preferable odors of sea urchin gonads;limonene, propyl acetate, acetone, dibromochloromethane. On the other hand, the analysis characterized three compounds with unpreferable odors;methyl mercaptane, dimethyl sulfide, and s-methyl thioacetate. Several VOCs from the gonads were derived from seaweeds, terrestrial plants, and fish flesh as food because M. nudus is omnivorous. Conclusion: This is the first study to identify VOCs from edible sea urchin gonads in the wild in Japan. These VOC data comprise a typical standard in order to evaluate a higher quality of sea urchin gonads.
文摘In the collaboration of RI Applications Team from RIKEN (Japan) and the Nuclear Chemistry Group from IMP (China), the short-lived Re carbonyl complexes were synthesized and investigated. As the lighter homologs of superheavy element Bh, Re belongs to period 6, group 7 of the periodic table. Short-lived Re isotopes with half-lives of several minutes were produced in the reactions of natGd(23Na7+, xn) 172?177Re at Nishina center of RIKEN.
文摘After the volatile Re carbonyl complexes were synthesized and their volatility was studied we performed another experiment to measure their chemical yields when He were used as the carrier gas. The same experimental setups were used except the low temperature isothermal chromatography device[1]. The natGd2O3 target and 23Na7+ion beam were used to produce short-lived Re isotopes, and the Gas-filled Recoil Ion Separator (GARIS) was employed to separate the evaporation residues[2]. High purity He gas and CO gas were used as the mixed gas. The depth of recoil chamber was 100 mm because of the long stop range in He gas, and the gas pressure was around 80 kpa. The total gas flow rate was 1 L/min.
文摘The production of ^(99)Mo is currently relying on nuclear reactors,however,most of the reactors are aged and most of them are about to be closed in the next decade.In recent years,other alternative routes to produce the radioisotope currently attract much attention and are discussed.
基金Supported by the National Natural Science Foundation of China(11575120,11822504,12075104)National Key Research and Development(R&D)programe of China(2021YFA1601500)+2 种基金Science Specialty Program of Sichuan University(2020SCUNL210)the support from Chinese Academy of Sciences for the project of Young Scientists in Basic Research(YSBR-099)"From 0 to 1 innovative"program.This work was partially supported by JSPS KAKENHI(JP19K03858)。
文摘The effects of the tensor force on the and decay nuclear matrix elements(NMEs)of,,,and are studied using the Hartree-Fock-Bogoliubov(HFB)plus proton-neutron quasi-particle random phase approximation(pnQRPA)model based on the Skyrme energy density functional.We include the full spectra of intermediate states with up to the energy cutoff E=60 MeV,which is sufficient for convergence of NME calculations.The isovector(IV)pairing and tensor interactions are considered in both HFB and QRPA calculations,while the isoscalar(IS)pairing interaction is included only in QRPA calculations.We found that the tensor force shifts Gamow-Teller(GT)transition strengths substantially to low-energy regions and enhances the decay NME.The inclusion of tensor force enhances the NME by approximately 13%for and and 30%for and,for a fixed IS pairing strength.We found that the intermediate 2-state makes an important contribution to the NME,which is slightly enhanced by the inclusion of the tensor force.We also found that the contribution of the state makes important differences through the inclusion of the tensor force,which enhances the contribution largely.However when the IS pairing strength is increased,the contributions from 1+states are rapidly reduced to be very small,resulting in even negative contributions.Thus,tensor and IS pairing effects cancel each other,making the net effect on the NME relatively small.Due to this cancellation,if the IS pairing strength is optimized separately for cases with and without the tensor interaction to reproduce the experimental NME,the consequent NME with the tensor interaction is close to that without the tensor interaction within a 10%difference.
基金supported by the the National Key R&D Program of China(Grant Nos.2022YFA1604900 and 2023YFA1606703)the National Natural Science Foundation of China(Grant Nos.12025501,12435007,12405133,and 12347180)+1 种基金China Postdoctoral Science Foundation(Grant No.2023M740189)the Postdoctoral Fellowship Program of CPSF(Grant No.GZC20233381).
文摘Hypernuclei,nuclei containing one or more hyperons,serve as unique laboratories for probing the non-perturbative quantum chromodynamics(QCD).Recent progress in hypernuclear physics,driven by advanced experimental techniques and theoretical innovations,is briefly reviewed with a focus on key findings and unresolved challenges,such as the precise determination of the hypertriton binding energy,investigations of charge symmetry breaking in mirror hypernuclei,and the search for exotic systems,including the neutral nnΛstate.Experimental breakthroughs,including invariant-mass analyses and femtoscopy studies in heavy-ion collisions,as well as high-resolutionγ-spectroscopy,have enabled precise studies of light hypernuclei and offered critical insights into the hyperon–nucleon interaction.Theoretical progress,including ab initio calculations based on chiral effective field theory and lattice QCD,has further enhanced our understanding of hyperon–nucleon and hyperon–hyperon interactions.
基金supported by the KAKENHI(19H05159,20K03959,and 21H00132(M.O.),and 23K03427(M.O.and G.J.W),24K17055(G.J.W))the National Natural Science Foundation of China(12275046(Z.Y.),12175239 and 12221005(J.J.W),11975033 and 12070131001(S.L.Z.))+2 种基金the Natural Science Foundation of Sichuan Province(2022NSFSC1795(Z.Y.))the National Key R&D Program of China(2020YFA0406400(J.J.W))the Chinese Academy of Sciences(YSBR-101(J.J.W)).
文摘We have investigated the internal structure of the open-and hidden-charmed(DD^(*)/DD^(*))molecules in the unified framework.We first fit the experimental lineshape of the Tt state and extract the DD^(*)interaction,from which the T is assumed to arise solely.Then we obtain the DD^(*)interaction by charge conjugation.Our results show that the DD*interaction is attractive but insufficient to form X(3872)as a bound state.Instead,its formation requires the crucial involvement of the coupled channel effect between the DD^(*)and cc components,although the cc accounts for approximately 1%only.Besides X(3872),we have obtained a higher-energy state around 3957.9 MeV with a width of 16.7 MeV,which may be a potential candidate for the X(3940).In J^(PC)=1^(+-)sector,we have found two states related to the iso-scalar X(3872)and h_(c)(2P),respectively.Our combined study provides valuable insights into the nature of these DD^(+)/DD^(+)exotic states.
文摘Research activities of nuclear physics at Radioactive Isotope Beam Factory over 10 years are reviewed and future directions are also discussed. Conceptual ideas in designing the facility as well as experimental devices are introduced. Special emphasis is given to highlighted results obtained at RIBF.
文摘Hypernuclear physics has become very exciting owing to new epoch-making experimental data. Recent progress in theoretical and experimental studies of hypernuclei and future developments in this field are discussed.
基金X.-G.H.was supported by NSFC(11535012,11675041)K.M.was supported by the China Postdoctoral Science Foundation(2017M621345)。
文摘We develop a covariant kinetic theory for massive fermions in a curved spacetime and an external electromagnetic field based on quantum field theory.We derive four coupled semi-classical kinetic equations accurate to O(ℏ),which describe the transports of particle number and spin degrees of freedom.The relationship with chiral kinetic theory is discussed.As an application,we study spin polarization in the presence of finite Riemann curvature and an electromagnetic field in both local and global equilibrium states.