A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor r...A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor ratios μpGEp/GMpand μnGEn/GMn. A quantitative description is obtained, assuming a mixing of a scalar bound state of 3(f f¯)fstructure with its corresponding vector (f f¯)fstate (f indicating massless elementary fermions). Only a few parameters are needed, mainly fixed by energy and momentum conservation. The nucleon stability is explained by an extra binding in the confinement potential, negative for electric and positive for magnetic binding of the proton, and opposite for the neutron. The stronger electric extra binding of the proton allows a decay of the neutron to proton and electron.展开更多
We present results of a series of experiments aimed at finding the most direct fingerprints of a phenomenon of nuclear chirality. These experiments brought a detailed knowledge of the so called partner bands in 132La,...We present results of a series of experiments aimed at finding the most direct fingerprints of a phenomenon of nuclear chirality. These experiments brought a detailed knowledge of the so called partner bands in 132La, 128Cs and 126Cs including absolute values of E2 and M1 transition probabilities obtained through the DSA (Doppler Shift Attenuation) method. Considering the indirect character of observables such as energies and transition rates we proposed measurement of the g-factor of a chosen state as a direct, ultimate test of chirality. Our experiment on the bandhead of partner bands in 128Cs showed feasibility of this approach. Measured value of the g-factor which suggests non-chiral character of this state leads to another puzzle in the chirality studies — how the chirality emerges with increasing spin of levels along a partner band.展开更多
Systematic calculations of low-lying energy levels,B(E2)transitions,and g factors of even-even tellurium isotopes with mass numbers from 128 to 140 are performed via the nucleon-pair approximation(NPA)of the shell mod...Systematic calculations of low-lying energy levels,B(E2)transitions,and g factors of even-even tellurium isotopes with mass numbers from 128 to 140 are performed via the nucleon-pair approximation(NPA)of the shell model with phenomenological multipole-multipole interactions.An optimal agreement is obtained between the calculated results and experimental data.The yrast band structures of nuclei below and above the N=82 shell closure are compared and discussed.In particular,the evolutionary differences of B(E2;2^(+)_(1)→0^(+)_(1))values and g(2^(+)_(1))factors,with respect to the symmetry of N=82,are attributed to the dominant contribution differences in neutron and proton excitations,respectively.展开更多
文摘A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor ratios μpGEp/GMpand μnGEn/GMn. A quantitative description is obtained, assuming a mixing of a scalar bound state of 3(f f¯)fstructure with its corresponding vector (f f¯)fstate (f indicating massless elementary fermions). Only a few parameters are needed, mainly fixed by energy and momentum conservation. The nucleon stability is explained by an extra binding in the confinement potential, negative for electric and positive for magnetic binding of the proton, and opposite for the neutron. The stronger electric extra binding of the proton allows a decay of the neutron to proton and electron.
文摘We present results of a series of experiments aimed at finding the most direct fingerprints of a phenomenon of nuclear chirality. These experiments brought a detailed knowledge of the so called partner bands in 132La, 128Cs and 126Cs including absolute values of E2 and M1 transition probabilities obtained through the DSA (Doppler Shift Attenuation) method. Considering the indirect character of observables such as energies and transition rates we proposed measurement of the g-factor of a chosen state as a direct, ultimate test of chirality. Our experiment on the bandhead of partner bands in 128Cs showed feasibility of this approach. Measured value of the g-factor which suggests non-chiral character of this state leads to another puzzle in the chirality studies — how the chirality emerges with increasing spin of levels along a partner band.
基金Supported by National Natural Science Foundation of China (11875188, 11905130 and 12075169)Sichuan Science and Technology Program (2019JDRC0017)+1 种基金the Doctoral Program of Southwest University of Science and Technology (18zx7147)Shanghai Sailing Program (19YF1434200)。
文摘Systematic calculations of low-lying energy levels,B(E2)transitions,and g factors of even-even tellurium isotopes with mass numbers from 128 to 140 are performed via the nucleon-pair approximation(NPA)of the shell model with phenomenological multipole-multipole interactions.An optimal agreement is obtained between the calculated results and experimental data.The yrast band structures of nuclei below and above the N=82 shell closure are compared and discussed.In particular,the evolutionary differences of B(E2;2^(+)_(1)→0^(+)_(1))values and g(2^(+)_(1))factors,with respect to the symmetry of N=82,are attributed to the dominant contribution differences in neutron and proton excitations,respectively.
