Theα-decay of neutron-deficient heavy nuclei far from stability is an indispensable spectroscopic tool to study their low-energy structure.220Pa,a trans-lead isotope near the shell closure N=126,its decay propertie...Theα-decay of neutron-deficient heavy nuclei far from stability is an indispensable spectroscopic tool to study their low-energy structure.220Pa,a trans-lead isotope near the shell closure N=126,its decay properties are still not well established,though it was studied in twoα-decay experiments 30 years ago[1,2].Recently,we applied successfully the modern digital pulse processing(DPP)technique[3,4]to the decay spectroscopy in the Z≥91 and N=128~131 region[5]and the decay chain of 220Pa was established at the first time.展开更多
Taking advantage of the largeγ-detector array Gammasphere and the recoil mass separator FMA,highspin states in 117Ba were investigated through the recoil-β-delayed proton decay tagging technique via the heavy-ion in...Taking advantage of the largeγ-detector array Gammasphere and the recoil mass separator FMA,highspin states in 117Ba were investigated through the recoil-β-delayed proton decay tagging technique via the heavy-ion induced fusion-evaporation reaction 64Zn(58Ni,2p3n)117Ba,at a beam energy of 305 MeV.Promptγrays belonging to 117Ba have been identified furthermore,a rotational band has been identified for the first time and presented as band A in Fig.1.展开更多
Isotope 223U synthesized and identified[1;2].αenergy of 8 780(40)keV and a half-life of 55(10)μs.Theαenergy was calculated by subtracting knownαenergy of 219Th from measured decay sum energy of 223U and its daught...Isotope 223U synthesized and identified[1;2].αenergy of 8 780(40)keV and a half-life of 55(10)μs.Theαenergy was calculated by subtracting knownαenergy of 219Th from measured decay sum energy of 223U and its daughter 219Th.Based on the advanced digital pulse processing technique,a new measurement forα-particle energy and half-life of 223U was performed at the gas-filled recoil separator,Spectrometer for Heavy Atoms and Nuclear Structure(SHANS).The isotope 223U was produced in the fusion-evaporation reaction 187Re(40Ar,p3n)223U.展开更多
We joined the SEASTAR (Shell Evolution And Search for 2+ energies At RIBF) collaboration at RIKEN and are analyzing the data of n-rich V and Mn isotopes with N 40. Three -rays in each of 63;65;67Mn are identified.The...We joined the SEASTAR (Shell Evolution And Search for 2+ energies At RIBF) collaboration at RIKEN and are analyzing the data of n-rich V and Mn isotopes with N 40. Three -rays in each of 63;65;67Mn are identified.The ?? coincidence relationships are being analyzed for establishing their level schemes. The progress in the data analysis is presented in Ref. [1].展开更多
The neutron-rich isotopes with N 40 below 68Ni, in many ways behave similar to the “island of inversion” nuclei with N 20. We report on the measurements of excited states of 63;65;67Mn via in-beam -ray spectrosc...The neutron-rich isotopes with N 40 below 68Ni, in many ways behave similar to the “island of inversion” nuclei with N 20. We report on the measurements of excited states of 63;65;67Mn via in-beam -ray spectroscopy. The experiment was performed at the Radioactive Isotope Beam Factory, RIKEN. Analysis of data for 63;65;67Mn obtained in the SEASTAR campaign has been done. A few transitions have been identified in each of them providing a chance to study the systematic structure evolution of n-rich Mn isotopes near N 40.展开更多
The region around the double-closed shell nucleus 208Pb has been particularly useful in studying residual interactions. The low spin isomers of the isotopes in the N=127, Z=8387 region have been identified in lastfif...The region around the double-closed shell nucleus 208Pb has been particularly useful in studying residual interactions. The low spin isomers of the isotopes in the N=127, Z=8387 region have been identified in lastfifty years except 213Rn[1??4]. In our recent implantation–r-a correlation study of the isotopes around the N=126 shell closure, a new ray is observed between the implantations and the decays of 213Rn, which could be due to the depopulation of the isomer of 213Rn mentioned above.展开更多
The study on the decay properties of new isotopes located far from the beta stability line is current the focus of nuclear physics. For isotopes in the region Z >82 and N <126, -emission prevails as radioactive ...The study on the decay properties of new isotopes located far from the beta stability line is current the focus of nuclear physics. For isotopes in the region Z >82 and N <126, -emission prevails as radioactive decay mode and -spectroscopy is the most important tool to obtain information on the nuclear structure. In the heavy nuclei region with N=124 and 126 isotones, an intruder state (h9=2.f7=2)8+ based on the attractive interaction of f7=2 protons and f5=2 neutrons has been significantly observed, which increases the binding energy of this configuration with increasing proton number.展开更多
Lifetime measurements of low-lying excited states in 87Zr and 87Nb have been performed via and coincidences. The 124 MeV 32S beam was delivered from the Sector-Focusing Cyclotron (SFC) of the Heavy Ion R-esearch Facil...Lifetime measurements of low-lying excited states in 87Zr and 87Nb have been performed via and coincidences. The 124 MeV 32S beam was delivered from the Sector-Focusing Cyclotron (SFC) of the Heavy Ion R-esearch Facility in Lanzhou (HIRFL). The parent nuclei 87Nb and 87Mo were produced by the respective reactions 58Ni (32S, 3p) and 58Ni (32S, 2p1n), at a beam energy 100 MeV through the 8 m Al degrader.展开更多
The Z=56 barium nuclei represent one of the best example of an isotopic chain to explore the evolution of quadrupole deformation as the neutron number decreases. The neutron-deficient barium isotopes with mass number ...The Z=56 barium nuclei represent one of the best example of an isotopic chain to explore the evolution of quadrupole deformation as the neutron number decreases. The neutron-deficient barium isotopes with mass number A ranging from 120 to 130 could be easily produced by the heavy-ion fusionevaporation reactions, and thus have been well studied in ray spectroscopy experiments.展开更多
Multi-nucleon transfer reaction plays an important role in the synthesis of new nuclides[1]. In the reactions of 20Ne+209Bi, some short-lived nuclei produced by transferring 26 nucleons were discovered. The experimen...Multi-nucleon transfer reaction plays an important role in the synthesis of new nuclides[1]. In the reactions of 20Ne+209Bi, some short-lived nuclei produced by transferring 26 nucleons were discovered. The experiment of 20Ne+209Bi was performed at gas-filled recoil separator in Lanzhou[2]. A 400 g/cm2 thick 209Bi target was bombarded with 20Ne beam delivered by accelerator HIRFL.展开更多
The first SEASTAR (Shell Evolution and Search for Two-plus energies At RIBF) campaign was carried out inMay 2014. We are analyzing the data for 58??63V and 63??66Mn.The experiment was performed at the Radioactive Isot...The first SEASTAR (Shell Evolution and Search for Two-plus energies At RIBF) campaign was carried out inMay 2014. We are analyzing the data for 58??63V and 63??66Mn.The experiment was performed at the Radioactive Isotope Beam Factory in RIKEN. A high-intensity 238U beamwas accelerated to bombard beryllium target to produce secondary beams. The B??ΔE??B method was applied toselect and purify secondary beams. An ionization chamber located at the focal point F7 (F11) measured the energyloss ΔE, yielding the fragments' element number Z in BigRIPS (ZDS)[1].展开更多
文摘Theα-decay of neutron-deficient heavy nuclei far from stability is an indispensable spectroscopic tool to study their low-energy structure.220Pa,a trans-lead isotope near the shell closure N=126,its decay properties are still not well established,though it was studied in twoα-decay experiments 30 years ago[1,2].Recently,we applied successfully the modern digital pulse processing(DPP)technique[3,4]to the decay spectroscopy in the Z≥91 and N=128~131 region[5]and the decay chain of 220Pa was established at the first time.
基金“100 Person Project”of Chinese Academy of Sciences and National Natural Science Foundation of China(11405224 11675225,U1632144,11635003).
文摘Taking advantage of the largeγ-detector array Gammasphere and the recoil mass separator FMA,highspin states in 117Ba were investigated through the recoil-β-delayed proton decay tagging technique via the heavy-ion induced fusion-evaporation reaction 64Zn(58Ni,2p3n)117Ba,at a beam energy of 305 MeV.Promptγrays belonging to 117Ba have been identified furthermore,a rotational band has been identified for the first time and presented as band A in Fig.1.
文摘Isotope 223U synthesized and identified[1;2].αenergy of 8 780(40)keV and a half-life of 55(10)μs.Theαenergy was calculated by subtracting knownαenergy of 219Th from measured decay sum energy of 223U and its daughter 219Th.Based on the advanced digital pulse processing technique,a new measurement forα-particle energy and half-life of 223U was performed at the gas-filled recoil separator,Spectrometer for Heavy Atoms and Nuclear Structure(SHANS).The isotope 223U was produced in the fusion-evaporation reaction 187Re(40Ar,p3n)223U.
文摘We joined the SEASTAR (Shell Evolution And Search for 2+ energies At RIBF) collaboration at RIKEN and are analyzing the data of n-rich V and Mn isotopes with N 40. Three -rays in each of 63;65;67Mn are identified.The ?? coincidence relationships are being analyzed for establishing their level schemes. The progress in the data analysis is presented in Ref. [1].
文摘The neutron-rich isotopes with N 40 below 68Ni, in many ways behave similar to the “island of inversion” nuclei with N 20. We report on the measurements of excited states of 63;65;67Mn via in-beam -ray spectroscopy. The experiment was performed at the Radioactive Isotope Beam Factory, RIKEN. Analysis of data for 63;65;67Mn obtained in the SEASTAR campaign has been done. A few transitions have been identified in each of them providing a chance to study the systematic structure evolution of n-rich Mn isotopes near N 40.
文摘The region around the double-closed shell nucleus 208Pb has been particularly useful in studying residual interactions. The low spin isomers of the isotopes in the N=127, Z=8387 region have been identified in lastfifty years except 213Rn[1??4]. In our recent implantation–r-a correlation study of the isotopes around the N=126 shell closure, a new ray is observed between the implantations and the decays of 213Rn, which could be due to the depopulation of the isomer of 213Rn mentioned above.
文摘The study on the decay properties of new isotopes located far from the beta stability line is current the focus of nuclear physics. For isotopes in the region Z >82 and N <126, -emission prevails as radioactive decay mode and -spectroscopy is the most important tool to obtain information on the nuclear structure. In the heavy nuclei region with N=124 and 126 isotones, an intruder state (h9=2.f7=2)8+ based on the attractive interaction of f7=2 protons and f5=2 neutrons has been significantly observed, which increases the binding energy of this configuration with increasing proton number.
文摘Lifetime measurements of low-lying excited states in 87Zr and 87Nb have been performed via and coincidences. The 124 MeV 32S beam was delivered from the Sector-Focusing Cyclotron (SFC) of the Heavy Ion R-esearch Facility in Lanzhou (HIRFL). The parent nuclei 87Nb and 87Mo were produced by the respective reactions 58Ni (32S, 3p) and 58Ni (32S, 2p1n), at a beam energy 100 MeV through the 8 m Al degrader.
基金“One Hundred Talents Program” of Chinese Academy of Sciences and National Natural Science Foundation of China(11405224)
文摘The Z=56 barium nuclei represent one of the best example of an isotopic chain to explore the evolution of quadrupole deformation as the neutron number decreases. The neutron-deficient barium isotopes with mass number A ranging from 120 to 130 could be easily produced by the heavy-ion fusionevaporation reactions, and thus have been well studied in ray spectroscopy experiments.
文摘Multi-nucleon transfer reaction plays an important role in the synthesis of new nuclides[1]. In the reactions of 20Ne+209Bi, some short-lived nuclei produced by transferring 26 nucleons were discovered. The experiment of 20Ne+209Bi was performed at gas-filled recoil separator in Lanzhou[2]. A 400 g/cm2 thick 209Bi target was bombarded with 20Ne beam delivered by accelerator HIRFL.
文摘The first SEASTAR (Shell Evolution and Search for Two-plus energies At RIBF) campaign was carried out inMay 2014. We are analyzing the data for 58??63V and 63??66Mn.The experiment was performed at the Radioactive Isotope Beam Factory in RIKEN. A high-intensity 238U beamwas accelerated to bombard beryllium target to produce secondary beams. The B??ΔE??B method was applied toselect and purify secondary beams. An ionization chamber located at the focal point F7 (F11) measured the energyloss ΔE, yielding the fragments' element number Z in BigRIPS (ZDS)[1].
