High-spin states in the beam energies. A new and 72 γ transitions odd-odd nucleus ^128I are investigated via the ^124 Sn（^7 Li,3n）^128 I reaction at 28 and 32 Me V level scheme of 12sI is established up to high-spi...High-spin states in the beam energies. A new and 72 γ transitions odd-odd nucleus ^128I are investigated via the ^124 Sn（^7 Li,3n）^128 I reaction at 28 and 32 Me V level scheme of 12sI is established up to high-spin states at I^π = 16, including 48 levels The present level scheme is largely different from the one in a recent publication due to identification of several doublet and triplet γ transitions and their proper placements in the level scheme. The high-spin level structure exhibits no obvious collective properties and is possibly associated with two and multi-quasiparticle configurations.展开更多
A new band in the odd proton nucleus ^123I is identified via in-beam γ-ray spectroscopy using the ^14N＋^116Cd reaction. This band shows up as doublets with the previously assigned π97/2 （vh11/2）^2 band. Possible...A new band in the odd proton nucleus ^123I is identified via in-beam γ-ray spectroscopy using the ^14N＋^116Cd reaction. This band shows up as doublets with the previously assigned π97/2 （vh11/2）^2 band. Possible configurations of the new band are discussed in the framework of the cranked shell model and the geometrical model It is argued that the new band might be a chiral partner of the previously known πg9/2 （vh11/2）2 band.展开更多
The China Accelerator Driven Subcritical System （China-ADS） project, which is a strategic plan and aims to design and build an ADS demonstration facility, has been proposed and launched actively in China. Injector ...The China Accelerator Driven Subcritical System （China-ADS） project, which is a strategic plan and aims to design and build an ADS demonstration facility, has been proposed and launched actively in China. Injector Ⅱ as one of the parallel injectors of China-ADS, and is prompted by the Institute of Modern Physics （IMP）. In this paper, a new scheme with full period lattice structure for the SC section is proposed. In the new scheme, there are sixteen periods, with one superconducting solenoid and one superconducting cavity included in each period. All of the elements are contained in four eryomodules. The dreadful influence of the mismatch caused by period structural change can be avoided, and the beam quality is favorable. In addition, this new scheme has certain advantages in reducing the project＇s difficulty and construction risk. The details of the design and beam dynamic simulation for the full period lattice structure are given in this paper.展开更多
Scaling analyses have been successfully applied to study the inclusive electron scattering(e, e') over the past few decades. In this study, we utilize the ψ' scaling function in momentum space to analyze the(...Scaling analyses have been successfully applied to study the inclusive electron scattering(e, e') over the past few decades. In this study, we utilize the ψ' scaling function in momentum space to analyze the(e, e') cross sections, where the nucleon momentum distributions are derived from self-consistent mean-field calculations. By further introducing the energy and momentum conservation in the scaling analysis, an improved ψ'scaling function is proposed to investigate the high-momentum part of the momentum distributions. Using the proposed scaling function, we systematically explore the effects of the nucleon-nucleon short-range correlation(NN-SRC) on the(e, e') cross sections. From the experimental(e, e') data, the NN-SRC strength is further extracted within the framework of the improved ψ'scaling function. The studies in this paper offer a new method to investigate the nucleon momentum distributions and the NN-SRC effects in nuclei.展开更多
The Intensity Heavy Ion Superconducting Linear Accelerator as the injector of the High Intensity Heavy- Ion Accelerator Facility, which is a new project proposed in China has been designed. One of the design options i...The Intensity Heavy Ion Superconducting Linear Accelerator as the injector of the High Intensity Heavy- Ion Accelerator Facility, which is a new project proposed in China has been designed. One of the design options in the low energy part is based on Quarter Wave Resonators （QWRs）. However, because of the unsymmetrical geometry of the cavity, there are dipole fields near the beam hole, which may steer the beam vertically, thus leading to emittance growth and beam loss. The effect of the dipole mode field is analyzed, and a method to overcome the beam steering effect by placing QWRs with opposite orientation is proposed in this paper. The simulation results show that the beam steering effect is reduced effectively by this method, and the deviation of the beam centroid is decreased from 2.87 mm to 0.1 mm. The emittance growth is also smaller.展开更多
The ADS（accelerator driven subcritical system） project was proposed by the Chinese Academy of Sciences.The initial proton beams delivered from an electron cyclotron resonance ion source can be effectively accelerate...The ADS（accelerator driven subcritical system） project was proposed by the Chinese Academy of Sciences.The initial proton beams delivered from an electron cyclotron resonance ion source can be effectively accelerated by 162.5 MHz 4.2 m long room temperature radio-frequency-quadrupoles（RFQ） operating in CW mode.To test the feasibility of this physical design,a new Fortran code for RFQ beam dynamics study,which is space charge dominated,was developed.This program is based on Particle-In-Cell（PIC） technique in the time domain.Using the RFQ structure designed for the CADS project,the beam dynamics behavior is performed.The well-known simulation code TRACK is used for benchmarks.The results given by these two codes show good agreements.Numerical techniques as well as the results of beam dynamics studies are presented in this paper.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 10825522, 1073505010 and 10775158, JSPS Invitation Fellowship （L00515）, the National Basic Research Program of China under Grant No 2007CB815005, and the Chinese Academy of Sciences.
文摘High-spin states in the beam energies. A new and 72 γ transitions odd-odd nucleus ^128I are investigated via the ^124 Sn（^7 Li,3n）^128 I reaction at 28 and 32 Me V level scheme of 12sI is established up to high-spin states at I^π = 16, including 48 levels The present level scheme is largely different from the one in a recent publication due to identification of several doublet and triplet γ transitions and their proper placements in the level scheme. The high-spin level structure exhibits no obvious collective properties and is possibly associated with two and multi-quasiparticle configurations.
基金Supported by the National Natural Science Foundation of China under Grant 10675053, the National Basic Research Program of China under Grant No 2007CB815005） and the Specialized Research Fund for the Doctoral Programme of Higher Education of China under Grant No 20060183048.
文摘A new band in the odd proton nucleus ^123I is identified via in-beam γ-ray spectroscopy using the ^14N＋^116Cd reaction. This band shows up as doublets with the previously assigned π97/2 （vh11/2）^2 band. Possible configurations of the new band are discussed in the framework of the cranked shell model and the geometrical model It is argued that the new band might be a chiral partner of the previously known πg9/2 （vh11/2）2 band.
基金Supported by National Natural Science Foundation of China(11079001)
文摘The China Accelerator Driven Subcritical System （China-ADS） project, which is a strategic plan and aims to design and build an ADS demonstration facility, has been proposed and launched actively in China. Injector Ⅱ as one of the parallel injectors of China-ADS, and is prompted by the Institute of Modern Physics （IMP）. In this paper, a new scheme with full period lattice structure for the SC section is proposed. In the new scheme, there are sixteen periods, with one superconducting solenoid and one superconducting cavity included in each period. All of the elements are contained in four eryomodules. The dreadful influence of the mismatch caused by period structural change can be avoided, and the beam quality is favorable. In addition, this new scheme has certain advantages in reducing the project＇s difficulty and construction risk. The details of the design and beam dynamic simulation for the full period lattice structure are given in this paper.
基金supported by the National Natural Science Foundation of China(Grant Nos.12035011,11975167,11947211,11905103,11881240623,11961141003,and 11505292)the National Key R&D Program of China(Grant No.2018YFA0404403)+3 种基金the Science and Technology Development Fund of Macao(Grant Nos.0048/2020/A1,and 008/2017/AFJ)the Shandong Provincial Natural Science Foundation,China(Grant No.ZR2020MA096)the Open Project of Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology(Grant No.NLK2021-03)the Key Laboratory of High Precision Nuclear Spectroscopy,Institute of Modern Physics,Chinese Academy of Sciences(Grant No.IMPKFKT2021001)。
文摘Scaling analyses have been successfully applied to study the inclusive electron scattering(e, e') over the past few decades. In this study, we utilize the ψ' scaling function in momentum space to analyze the(e, e') cross sections, where the nucleon momentum distributions are derived from self-consistent mean-field calculations. By further introducing the energy and momentum conservation in the scaling analysis, an improved ψ'scaling function is proposed to investigate the high-momentum part of the momentum distributions. Using the proposed scaling function, we systematically explore the effects of the nucleon-nucleon short-range correlation(NN-SRC) on the(e, e') cross sections. From the experimental(e, e') data, the NN-SRC strength is further extracted within the framework of the improved ψ'scaling function. The studies in this paper offer a new method to investigate the nucleon momentum distributions and the NN-SRC effects in nuclei.
基金Supported by National Science Foundation of China(11079001)
文摘The Intensity Heavy Ion Superconducting Linear Accelerator as the injector of the High Intensity Heavy- Ion Accelerator Facility, which is a new project proposed in China has been designed. One of the design options in the low energy part is based on Quarter Wave Resonators （QWRs）. However, because of the unsymmetrical geometry of the cavity, there are dipole fields near the beam hole, which may steer the beam vertically, thus leading to emittance growth and beam loss. The effect of the dipole mode field is analyzed, and a method to overcome the beam steering effect by placing QWRs with opposite orientation is proposed in this paper. The simulation results show that the beam steering effect is reduced effectively by this method, and the deviation of the beam centroid is decreased from 2.87 mm to 0.1 mm. The emittance growth is also smaller.
基金Supported by National Natural Science Foundation of China(11079001,91026001)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA03030100)
文摘The ADS（accelerator driven subcritical system） project was proposed by the Chinese Academy of Sciences.The initial proton beams delivered from an electron cyclotron resonance ion source can be effectively accelerated by 162.5 MHz 4.2 m long room temperature radio-frequency-quadrupoles（RFQ） operating in CW mode.To test the feasibility of this physical design,a new Fortran code for RFQ beam dynamics study,which is space charge dominated,was developed.This program is based on Particle-In-Cell（PIC） technique in the time domain.Using the RFQ structure designed for the CADS project,the beam dynamics behavior is performed.The well-known simulation code TRACK is used for benchmarks.The results given by these two codes show good agreements.Numerical techniques as well as the results of beam dynamics studies are presented in this paper.
