Pear-shaped nuclei

2021 ◽  
pp. 2130013
Author(s):  
S. C. Pancholi
Keyword(s):  
Nuclear Energy ◽  
High Efficiency ◽  
Transition Probabilities ◽  
Coulomb Excitation ◽  
Energy Levels ◽  
Experimental Investigations ◽  
Gamma Detector ◽  
Axially Symmetric ◽  
Detector Arrays ◽  
Electric Transition

This brief review presents current experimental evidence on the existence of deformed axially symmetric but reflection asymmetric or pear shapes in nuclei. A summary of the main findings on the properties of nuclear energy levels and electric transition probabilities is given. These experimental investigations have been possible due to the development of high efficiency gamma-detector arrays and production and availability of exotic radioactive ion beams which facilitated in-beam Coulomb excitation. The nuclear structure of odd-mass pear-shaped nuclei has assumed importance as they can be vital in solving some of the fundamental problems in physics. This paper is sequel to the publication of the book by the author on Pear-shaped Nuclei (World Scientific, 2020).

Coulomb excitation of low-energy levels in 45Sc

1979 ◽  
Vol 57 (8) ◽  
pp. 1196-1203 ◽  
Author(s):  
V. U. Patil ◽  
R. G. Kulkarni
Keyword(s):  
Gamma Ray ◽  
Transition Probabilities ◽  
Coulomb Excitation ◽  
Energy Levels ◽  
Negative Parity ◽  
Core Excitation ◽  
Mixing Ratios ◽  
Reduced Transition Probabilities ◽  
Excitation Model ◽  
First Time

Low-lying negative parity levels in 45Sc were Coulomb excited with 2.5 to 3.5 MeV protons and 4 to 5 MeV 4He ions to test the weak coupling core-excitation model. A Ge(Li) detector was used to measure the gamma-ray yields. The 543, 976, 1408, and 1662 keV levels in 45Sc were Coulomb excited for the first time. Gamma-ray angular distributions were measured at 3.0 MeV proton energy in deducing multipole mixing ratios and spin values. Energy level measurements (in units of kiloelectronvolts) and spin values obtained are as follows: 976, 5/2, 7/2 and 1408, 7/2. The E2 and M1 reduced transition probabilities were determined for the six states. The 376, 720, 1237, 1408, and 1662 keV levels have properties consistent with the interpretation of coupling a 1f7/2 proton to the first 2+ core state.

scholarly journals Description of the energy levels and electric quadrupole transitions of the 92Nb and 92Mo nuclei using nuclear shell model

2021 ◽  
Author(s):  
Mustafa Mohammed Jabbar ◽  
Keyword(s):  
Transition Probabilities ◽  
Transition Probability ◽  
Energy Levels ◽  
Electric Quadrupole ◽  
Electric Quadrupole Transition ◽  
Modified Surface ◽  
Electric Transition ◽  
Experimental Values ◽  
Nuclear Shell ◽  
Good Agreement

In current study ,92Nb and 92Mo isotopes have been determined for calculating energy levels and electric quadrupole transition probabilities. Two interaction have been applied in this study are surface delta and modified surface delta interactions. The calculations have been achieved by using appropriate effective charges for proton and neutron as well as parameter length of harmonic potential. Computed results have been compared with the experimental values. After this comparison, energy and the transition probability values have a good agreement with the experimental values, also there are values of the total angular momentum and parity are determined and confirmed for some of the experimental energies, undetermined and unconfirmed experimentally. Theoretically, new values of quadrupole electric transition probabilities have been explored which have not been known in the experimental data.

CALCULATIONS OF REDUCED PROBABILITY FOR E2 TRANSITIONS IN BETA AND GAMMA BANDS

1963 ◽  
Vol 41 (5) ◽  
pp. 742-749 ◽  
Author(s):  
M. A. Preston ◽  
D. Kiang
Keyword(s):  
Nuclear Energy ◽  
Energy Levels ◽  
Axially Symmetric ◽  
Nuclear Energy Levels ◽  
Vibrational Bands

For convenience in analysis of experiments on nuclear energy levels, we list specific formulas for the reduced probabilities of E2 transitions between rotational levels built upon β- and γ-vibrational bands for axially symmetric even–even nuclei.

scholarly journals Calculation of quadrupole deformation parameter β2 from reduced transition probability B(E2) for 0+1 → 2+1 transitions at even-even 62-68Zn isotopes

2021 ◽  
Vol 22 (1) ◽  
pp. 30-41
Author(s):  
Fatema Hameed Obeed ◽  
Ali Khalaf Hasan
Keyword(s):  
Transition Probabilities ◽  
Transition Probability ◽  
Energy Levels ◽  
Complete Agreement ◽  
Quadrupole Moments ◽  
Core Nucleus ◽  
Model Calculations ◽  
Deformation Parameters ◽  
Electric Transition ◽  
Experimental Values

In this work the excited energy levels, reduced transition probabilities B(E2)↑, intrinsic quadrupole moments, and deformation parameters have been calculated for 62-68Zn isotopes with neutrons number N = 32, 34, 36 and 38. NuSheIIX code has been applied for all energy states of fp-shell nuclei. Shell-model calculations for the zinc isotopes have been carried out with active particles distributed in the lp3/2, 0f5/2, and lp1/2 orbits outside doubly magic closed 56Ni core nucleus. By using f5p model space and f5pvh interaction, the theoretical results have been obtained and compared with the available experimental results. The excited energies values, electric transition probability B(E2), intrinsic quadrupole moment Q0, and deformation parameters β2 have appeared in complete agreement with the experimental values. As well as, the energy levels have been confirmed and determined for the angular momentum and parity of experimental values that have not been well established and determined experimentally. On the other hand, it has been predicted some of the new energy levels and electric transition probabilities for the 62-68Zn isotopes under this study which were previously unknown in experimental information.

Rotational Nuclear Energy Levels from Coulomb Excitation

1954 ◽  
Vol 94 (5) ◽  
pp. 1399-1400 ◽  
Author(s):  
G. M. Temmer ◽  
N. P. Heydenburg
Keyword(s):  
Nuclear Energy ◽  
Coulomb Excitation ◽  
Energy Levels ◽  
Nuclear Energy Levels

scholarly journals New Transition and Energy Levels of Three-Times Ionized Krypton (Kr IV)

Atoms ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 48
Author(s):  
M. Raineri ◽  
M. Gallardo ◽  
J. Reyna Almandos ◽  
A. G. Trigueiros ◽  
C. J. B. Pagan
Keyword(s):  
Transition Probabilities ◽  
Energy Levels ◽  
Pulsed Discharge ◽  
Core Polarization ◽  
Polarization Effects ◽  
Hartree Fock ◽  
Theta Pinch ◽  
New Energy ◽  
First Time

A capillary pulsed-discharge and a theta-pinch were used to record Kr spectra in the region of 330–4800 Å. A set of 168 transitions of these spectra were classified for the first time. We extended the analysis to twenty-five new energy levels belonging to 3s23p24d, 3s23p25d even configurations. We calculated weighted transition probabilities (gA) for all of the experimentally observed lines and lifetimes for new energy levels using a relativistic Hartree–Fock method, including core-polarization effects.

scholarly journals Low Power Cusped Field Thruster Developed for the Space-Borne Gravitational Wave Detection Mission in China

2021 ◽  
Vol 11 (14) ◽  
pp. 6549
Author(s):  
Hui Liu ◽  
Ming Zeng ◽  
Xiang Niu ◽  
Hongyan Huang ◽  
Daren Yu
Keyword(s):  
Low Power ◽  
Gravitational Wave ◽  
Attitude Control ◽  
High Efficiency ◽  
Experimental Investigations ◽  
Attitude Control System ◽  
Gravitational Wave Detection ◽  
Wave Detection ◽  
Wide Range ◽  
Institute Of Technology

The microthruster is the crucial device of the drag-free attitude control system, essential for the space-borne gravitational wave detection mission. The cusped field thruster (also called the High Efficiency Multistage Plasma Thruster) becomes one of the candidate thrusters for the mission due to its low complexity and potential long life over a wide range of thrust. However, the prescribed minimum of thrust and thrust noise are considerable obstacles to downscaling works on cusped field thrusters. This article reviews the development of the low power cusped field thruster at the Harbin Institute of Technology since 2012, including the design of prototypes, experimental investigations and simulation studies. Progress has been made on the downscaling of cusped field thrusters, and a new concept of microwave discharge cusped field thruster has been introduced.

scholarly journals Roll Bonding of Al-Based Composite Reinforced with C10 Steel Expanded Mesh Inlay

Metals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1044
Author(s):  
Yaroslav Frolov ◽  
Maxim Nosko ◽  
Andrii Samsonenko ◽  
Oleksandr Bobukh ◽  
Oleg Remez
Keyword(s):  
Impact Energy ◽  
High Efficiency ◽  
Shape Change ◽  
Experimental Investigations ◽  
Aluminum Composite ◽  
Rolling Mills ◽  
Roll Bonding ◽  
Finite Element Software ◽  
Steel Mesh ◽  
Bonded Composite

The most complex issue related to the design of high efficiency composite materials is the behavior of the reinforcing component during the bonding process. This study presents numerical and experimental investigations of the shape change in the reinforcing inlay in an aluminum-steel mesh-aluminum composite during roll-bonding. A flat composite material consisting of two outer strips of an EN AW 1050 alloy and an inlay of expanded C10 steel mesh was obtained via hot roll bonding with nominal rolling reductions of 20%, 30%, 40% and 50% at a temperature of 500 °C. The experimental procedure was carried out using two separate rolling mills with diameters equal to 135 and 200 mm, respectively. A computer simulation of the roll bonding was performed using the finite element software QForm 9.0.10 by Micas Simulations Limited, Oxford, UK. The distortion of the mesh evaluated via the change in angle between its strands was described using computer tomography scanning. The dependence of the absorbed impact energy of the roll bonded composite on the parameters of the deformation zone was found. The results of the numerical simulation of the steel mesh shape change during roll bonding concur with the data from micro-CT scans of the composites. The diameter of rolls applied during the roll bonding, along with rolling reduction and temperature, have an influence on the resulting mechanical properties, i.e., the absorbed bending energy. Generally, the composites with reinforcement exhibit up to 20% higher impact energy in comparison with the non-reinforced composites.

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