Two parameter expressions for rotational spectra viz. variable moment of inertia (VMI), ab formula and three parameter Harris w2 expansion are used to assign the band head spins (I0) of four rotational superdeform...Two parameter expressions for rotational spectra viz. variable moment of inertia (VMI), ab formula and three parameter Harris w2 expansion are used to assign the band head spins (I0) of four rotational superdeformed bands in 86Zr. The least-squares fitting method is employed to obtain the band head spins of these four bands in the A - 80 mass region. Model parameters are extracted by fitting of intraband y-ray energies, so as to obtain a minimum root-mean-square (rms) deviation between the calculated and the observed transition energies. The calculated transition energies are found to depend sensitively on the assigned spins. Whenever an accurate band head spin is assigned, the calculated transition energies axe in agreement with the experimental transition energies. The dynamic moment of inertia is also extracted and its variation with rotational frequency is investigated. Since a better agreement of band head spin with experimental results is found using the VMI model, it is a more powerful tool than the ab formula and Harris w2 expansion.展开更多
The systematics of kinematic moment of inertia J and dynamic moment of inertia J of superdeformed(SD) bands in A -130, 150, 190 mass regions have been studied. We have obtained the values of J^(1) and J^(2)for a...The systematics of kinematic moment of inertia J and dynamic moment of inertia J of superdeformed(SD) bands in A -130, 150, 190 mass regions have been studied. We have obtained the values of J^(1) and J^(2)for all the SD bands observed in the A-130, 150, 190 mass regions by using the experimental intraband E2 transition energies. The result of this work includes the variation of J with the product of valence proton and neutron numbers(NpNn). The phenomenon of band mixing has been observed in the A -130, 150 mass regions and band crossing has been observed in the A-190 mass region. The systematics also includes the variation of J with the product of valence proton and neutron numbers(NpNn). Evidence of staggering behaviour has been observed in all three A-130, 150 and 190 mass regions. We present for the first time the variation of J^(1)and J^(2)of SD bands in the A-130, 150, 190 mass regions with NpNn.展开更多
A systematic study of the product((E(22^+)/E(21^+))*B(E2)↑) is carried out in the major shell space Z=50-82,N=82-126 within the framework of the asymmetric rotor model where the asymmetry parameter γ0re...A systematic study of the product((E(22^+)/E(21^+))*B(E2)↑) is carried out in the major shell space Z=50-82,N=82-126 within the framework of the asymmetric rotor model where the asymmetry parameter γ0reflects change in the nuclear structure.A systematic study of the product((E(2^+)/E(2^+))*B(E2)↑) with neutron number N is also discussed.The product((E(22^+)/E(21^+))*B(E2)↑) provides a direct correlation with the asymmetry parameter γ0.The effect of subshells is visible in Ba-Gd nuclei with N 〉 82,but not in Hf-Pt nuclei with N 〉 104.We study,for the first time,the dependency of the product((E(22^+)/E(21^+))*B(E2)↑) on the asymmetry parameterγ0.展开更多
The power index formula has been used to obtain the band head spin(I0) of all the superdeformed(SD) bands in Hg isotopes. A least squares fitting approach is used. The root mean square deviations between the determine...The power index formula has been used to obtain the band head spin(I0) of all the superdeformed(SD) bands in Hg isotopes. A least squares fitting approach is used. The root mean square deviations between the determined and the observed transition energies are calculated by extracting the model parameters using the power index formula. Whenever definite spins are available, the determined and the observed transition energies are in accordance with each other. The computed values of dynamic moment of inertia J~((2)) obtained by using the power index formula and its deviation with the rotational frequency is also studied. Excellent agreement is shown between the calculated and the experimental results for J~((2)) versus the rotational frequency. Hence, the power index formula works very well for all the SD bands in Hg isotopes expect for195Hg(2, 3, 4).展开更多
A systematic dependence of shape fluctuation energy product SFE * B(E2)↑ and rotational energy product ROTE * B(E2)↑ on the valence nucleon product Np Nn is carried out in the Z = 50-82,N = 82-126 major shell ...A systematic dependence of shape fluctuation energy product SFE * B(E2)↑ and rotational energy product ROTE * B(E2)↑ on the valence nucleon product Np Nn is carried out in the Z = 50-82,N = 82-126 major shell space.For the shape transitional nuclei,the product SFE*B(E2)↑ drops to zero and becomes negative,indicating direct dependence on N_pN_n.A relative rise,on the other hand,is observed in the product ROTE*B(E2) ↑plotted against N_pN_n for all the nuclei in Z = 50-82 and N = 82-126.In the N 〉 104 region,large positive values of the product SFE * B(E2) ↑ are observed for the Pt nucleus,which indicates sphericity.A systematic study of the product SFE * B(E2)↑ and ROTE * B(E2) ↑ with atomic number Z is also discussed.The products SFE * B(E2) ↑and ROTE * B(E2) ↑ vary sharply with Z for the N = 88 isotones.We discuss here for the first time the correlation between SFE * B(E2) ↑ and ROTE * B(E2) ↑ with valence nucleon product N_pN_n.展开更多
基金Financial support from the Department of Science and Technology,Government of India is gratefully ac-knowledged
文摘Two parameter expressions for rotational spectra viz. variable moment of inertia (VMI), ab formula and three parameter Harris w2 expansion are used to assign the band head spins (I0) of four rotational superdeformed bands in 86Zr. The least-squares fitting method is employed to obtain the band head spins of these four bands in the A - 80 mass region. Model parameters are extracted by fitting of intraband y-ray energies, so as to obtain a minimum root-mean-square (rms) deviation between the calculated and the observed transition energies. The calculated transition energies are found to depend sensitively on the assigned spins. Whenever an accurate band head spin is assigned, the calculated transition energies axe in agreement with the experimental transition energies. The dynamic moment of inertia is also extracted and its variation with rotational frequency is investigated. Since a better agreement of band head spin with experimental results is found using the VMI model, it is a more powerful tool than the ab formula and Harris w2 expansion.
文摘The systematics of kinematic moment of inertia J and dynamic moment of inertia J of superdeformed(SD) bands in A -130, 150, 190 mass regions have been studied. We have obtained the values of J^(1) and J^(2)for all the SD bands observed in the A-130, 150, 190 mass regions by using the experimental intraband E2 transition energies. The result of this work includes the variation of J with the product of valence proton and neutron numbers(NpNn). The phenomenon of band mixing has been observed in the A -130, 150 mass regions and band crossing has been observed in the A-190 mass region. The systematics also includes the variation of J with the product of valence proton and neutron numbers(NpNn). Evidence of staggering behaviour has been observed in all three A-130, 150 and 190 mass regions. We present for the first time the variation of J^(1)and J^(2)of SD bands in the A-130, 150, 190 mass regions with NpNn.
文摘A systematic study of the product((E(22^+)/E(21^+))*B(E2)↑) is carried out in the major shell space Z=50-82,N=82-126 within the framework of the asymmetric rotor model where the asymmetry parameter γ0reflects change in the nuclear structure.A systematic study of the product((E(2^+)/E(2^+))*B(E2)↑) with neutron number N is also discussed.The product((E(22^+)/E(21^+))*B(E2)↑) provides a direct correlation with the asymmetry parameter γ0.The effect of subshells is visible in Ba-Gd nuclei with N 〉 82,but not in Hf-Pt nuclei with N 〉 104.We study,for the first time,the dependency of the product((E(22^+)/E(21^+))*B(E2)↑) on the asymmetry parameterγ0.
文摘The power index formula has been used to obtain the band head spin(I0) of all the superdeformed(SD) bands in Hg isotopes. A least squares fitting approach is used. The root mean square deviations between the determined and the observed transition energies are calculated by extracting the model parameters using the power index formula. Whenever definite spins are available, the determined and the observed transition energies are in accordance with each other. The computed values of dynamic moment of inertia J~((2)) obtained by using the power index formula and its deviation with the rotational frequency is also studied. Excellent agreement is shown between the calculated and the experimental results for J~((2)) versus the rotational frequency. Hence, the power index formula works very well for all the SD bands in Hg isotopes expect for195Hg(2, 3, 4).
文摘A systematic dependence of shape fluctuation energy product SFE * B(E2)↑ and rotational energy product ROTE * B(E2)↑ on the valence nucleon product Np Nn is carried out in the Z = 50-82,N = 82-126 major shell space.For the shape transitional nuclei,the product SFE*B(E2)↑ drops to zero and becomes negative,indicating direct dependence on N_pN_n.A relative rise,on the other hand,is observed in the product ROTE*B(E2) ↑plotted against N_pN_n for all the nuclei in Z = 50-82 and N = 82-126.In the N 〉 104 region,large positive values of the product SFE * B(E2) ↑ are observed for the Pt nucleus,which indicates sphericity.A systematic study of the product SFE * B(E2)↑ and ROTE * B(E2) ↑ with atomic number Z is also discussed.The products SFE * B(E2) ↑and ROTE * B(E2) ↑ vary sharply with Z for the N = 88 isotones.We discuss here for the first time the correlation between SFE * B(E2) ↑ and ROTE * B(E2) ↑ with valence nucleon product N_pN_n.