In search of empirical rule relating E21+  and B(E2; 01+→21+)  in asymmetric even–even nuclei of mass region A = 90–120

The quadrupole deformation β are extracted independently from energy and transition rates. The set of asymmetric parameters γ are obtained from energy ratio [Formula: see text]. It is observed that the set of β values evaluated from B(E2) are closer to the values of β extracted from [Formula: see text] on considering the Grodzins empirical rule (Grodzins. Phys. Lett. 2, 88 (1962)) with uncertainty in even Mo, Ru, and Pd nuclei. The moment of inertia [Formula: see text] generating the yrast band in these nuclei is evaluated from [Formula: see text] using the asymmetric rotor model (Davydov and Filippov. Nucl. Phys. 8, 237 (1958)). The β, γ, and I0 values have good correlations with NpNn. In addition, β and I0 are related linearly in general. This systematic relate [Formula: see text] [Formula: see text] and asymmetric deformation γ that enables one to predict [Formula: see text], the static quadrupole moment Q0 and quadrupole deformation β of those nuclei whose only [Formula: see text] is known.

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Ground and gamma band energy systematics in even xenon and barium nuclei

Canadian Journal of Physics ◽

10.1139/p09-093 ◽

2010 ◽

Vol 88 (3) ◽

pp. 201-209

Author(s):

Yuvraj Singh ◽

Chhail Bihari ◽

A. K. Varshney ◽

S. K. Dhiman ◽

K. K. Gupta ◽

...

Keyword(s):

Coupling Parameter ◽

Structural Evolution ◽

Gamma Band ◽

External Parameter ◽

Yrast Band ◽

Large Asymmetry ◽

Inertia Parameters ◽

Asymmetric Rotor ◽

The Moment ◽

Vibration Coupling

Rotation–vibration coupling parameter b at different spins is calculated on fitting the experimental energy for each nucleus in the framework of the General Asymmetric Rotor Model (Zhi. Phys. Rev. C, 51, 141 (1995)). Taking the even and odd spin energy sequences of the gamma band as separate bands besides the yrast band at large asymmetry (γ ≥ 20°), three values of the moment of inertia parameters a (ar, ae, and ao) are calculated from the band head energies. A striking correlation in a and b versus the product of the number of valance protons and neutrons (NpNn) is obtained. These trajectories and the γ versus NpNn correlation (Yan et al. Phys. Rev. C, 48, 1046 (1993)) are capable of predicting the unknown energies of the ground and gamma bands of even xenon and barium nuclei, knowing only an external parameter NpNn. This introduces the possibility of a simpler description of the structural evolution of these transitional nuclei.

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Evidence of rigid triaxiality in some xenon nuclei

Canadian Journal of Physics ◽

10.1139/p07-081 ◽

2007 ◽

Vol 85 (8) ◽

pp. 899-910 ◽

Cited By ~ 8

Author(s):

M Singh ◽

C Bihari ◽

Y Singh ◽

D Gupta ◽

A K Varshney ◽

...

Keyword(s):

Hilbert Space ◽

Moment Of Inertia ◽

Vibrational Band ◽

Current Interest ◽

Asymmetric Rotor ◽

The Moment ◽

21.60 Ev ◽

Gamma Vibrational Band ◽

Rotor Model

The present study deals with a topic of current interest, getting clear evidence for triaxiality in the 120–130 Xe nuclei near A = 130. The odd–even staggering in a so-called gamma-vibrational band may be treated using the asymmetric rotor model (ARM) on employing the Lipas parameter. The Hilbert space is too limited to describe the full variation of the moment of inertia and, therefore, the Lipas Ansatz ismade to correct the ARM energies, which conserve the good result for B(E2) values.PACS Nos.: 21.10.Re, 21.60.Ev, 27.60.+j

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Pathological behavior in the spectral statistics of the asymmetric rotor model

Physical Review E ◽

10.1103/physreve.64.066201 ◽

2001 ◽

Vol 64 (6) ◽

Cited By ~ 1

Author(s):

V. R. Manfredi ◽

L. Salasnich

Keyword(s):

Asymmetric Rotor ◽

Spectral Statistics ◽

Pathological Behavior ◽

Rotor Model

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Mean life predictions in respect of Kπ = 2+ collective excitations in deformed even nuclei

Canadian Journal of Physics ◽

10.1139/p82-196 ◽

1982 ◽

Vol 60 (10) ◽

pp. 1461-1470 ◽

Cited By ~ 5

Author(s):

V. P. Varshney ◽

K. K. Gupta ◽

A. K. Chaubey ◽

D. K. Gupta

Keyword(s):

Branching Ratios ◽

Collective Excitations ◽

Medium Mass ◽

Theoretical Predictions ◽

Asymmetric Rotor ◽

The Mean ◽

The Asymmetry ◽

Experimental Values ◽

Life Predictions ◽

Rotor Model

The figures of Gupta et al. (Nuovo Cimento B, 58, 101 (1980)) regarding the E2 transitions in heavy mass nuclei have been modified. Medium mass nuclei of range 20° < γ < 30°, which reflect the asymmetry of the nuclei, have been included. We have employed the asymmetric rotor model dependent Q0 for the sake of consistency in theoretical predictions instead of its experimental values. It is observed that theoretical values of B(E2) branching ratios viz. 2+′ → 2+/0+, 2+′ → 2+/2+ → 0+, and 2+′ → 0+/2+ → 0+ coincide excellently with experimental ones for the nuclei, which consistently show a low-lying second 2+ state at about the same energy as the first 4+ state. In general, the agreement with experimental values is found to be within a factor of two. On using absolute B(E2: 2+ → 0+) and γ data, the values of B(E2: 2+′ → 0+), B(E2: 2+′ → 2+), and the mean life of 2+′ states have been predicted.

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Triaxiality in 146,148Sm nuclei

Canadian Journal of Physics ◽

10.1139/p89-020 ◽

1989 ◽

Vol 67 (2-3) ◽

pp. 131-134 ◽

Cited By ~ 1

Author(s):

A. K. Varshney ◽

K. K. Gupta ◽

D. K. Gupta ◽

R. K. Tyagi

Keyword(s):

Energy Levels ◽

Branching Ratios ◽

Energy Ratio ◽

Poor Agreement ◽

Model Framework ◽

Expansion Technique ◽

Asymmetric Rotor ◽

Boson Expansion ◽

Spherical Nuclei ◽

Rotor Model

Recently, attempts have been made to use the dynamic pairing plus quadrupole model to evaluate B(E2) values, B(E2) branching ratios, and low-lying energy levels for 146,148Sm nuclei, which are in poor agreement with experiment. Application of the boson expansion technique on 148Sm shows too much splitting and an incorrect order for the quintet states, while other properties have not been discussed. In the present work, 146,148Sm nuclei have been described using an asymmetric rotor model framework. The nonaxiality parameter (γ) has been evaluated using the energy ratio E2+′/E6+. Remarkable success has been achieved in explaining the correct ordering of known low-lying energy levels, B(E2) values, and B(E2) branching ratios, which indicate that the so-called spherical nuclei may be treated as triaxial.

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