THE SHAPE TRANSITIONS IN ROTATING NUCLEI

The effect of rotation on the shapes of nuclei is discussed within Strutinsky's optimal-shape approach generalized to nonaxial deformations. The limiting value of the angular momentum at which the nucleus loses its stability with respect to fission, as well as the angular momentum at which the Jacobi transition takes place, are calculated as function of the fissility parameter. The results are compared with those obtained for triaxial spheroidal forms.

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JACOBI SHAPE TRANSITIONS WITHIN THE LSD MODEL AND THE SKYRME-ETF APPROACH

International Journal of Modern Physics E ◽

10.1142/s0218301308009598 ◽

2008 ◽

Vol 17 (01) ◽

pp. 100-109 ◽

Cited By ~ 2

Author(s):

JOHANN BARTEL ◽

KRZYSZTOF POMORSKI

Keyword(s):

Present Approach ◽

Thomas Fermi ◽

The Stability ◽

Shape Transitions ◽

Rotating Nuclei

The "Modified Funny-Hills parametrisation" is used together with the Lublin-Strasbourg Drop Model to evaluate the stability of rotating nuclei. The Jacobi transition into triaxial shapes is studied. By a comparison with selfconsistent semiclassical calculations in the framework of the Extended Thomas-Fermi method, the validity of the present approach is demonstrated and possible improvements are indicated.

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JACOBI BIFURCATION IN HOT ROTATING NUCLEI WITH A LSD + YUKAWA FOLDED APPROACH

International Journal of Modern Physics E ◽

10.1142/s0218301309013130 ◽

2009 ◽

Vol 18 (04) ◽

pp. 986-995 ◽

Cited By ~ 4

Author(s):

JOHANN BARTEL ◽

BOZENA NERLO-POMORSKA ◽

KRZYSZTOF POMORSKI

Keyword(s):

Angular Momentum ◽

Nuclear Energy ◽

Nuclear Temperature ◽

The Stability ◽

Rotational Angular Momentum ◽

Rotating Nuclei

The "Modified Funny-Hills parametrisation" is used together with the Lublin-Strasbourg Drop Model and Strutinsky type shell corrections to determine the stability of hot rotating nuclei. Both the macroscopic and the microscopic part of the nuclear energy are evaluated by taking into account their dependence on the nuclear temperature and the rotational angular momentum. The Jacobi transition into triaxial shapes and the centrifugal-fission instability are studied.

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Shape transitions in hot rotating nuclei

Nuclear Physics A ◽

10.1016/s0375-9474(01)00622-4 ◽

2001 ◽

Vol 687 (1-2) ◽

pp. 206-211 ◽

Cited By ~ 1

Author(s):

A.L. Goodman

Keyword(s):

Shape Transitions ◽

Rotating Nuclei

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Dynamo Action in Evolved Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100079872 ◽

1991 ◽

Vol 130 ◽

pp. 336-341

Author(s):

David F. Gray

Keyword(s):

Angular Momentum ◽

Magnetic Fields ◽

Rotation Rate ◽

Magnetic Activity ◽

Dynamo Action ◽

Rotation Rates ◽

Evolved Stars ◽

Solar Type ◽

Limiting Value

AbstractEvolved stars tell us a great deal about dynamos. The granulation boundary shows us where solar-type convection begins. Since activity indicators also start at this boundary, it is a good bet that solar-type convection is an integral part of dynamo activity for all stars. The rotation boundary tells us where the magnetic fields of dynamos become effective in dissipating angular momentum, and rotation beyond the boundary tells us the limiting value needed for a dynamo to function. The observed uniqueness of rotation rates after the rotation boundary is crossed can be understood through the rotostat hypothesis. Quite apart from the reason for the unique rotation rate, its existence can be used to show that magnetic activity of giants is concentrated to the equatorial latitudes, as it is in the solar case. The coronal boundary in the H-R diagram is probably nothing more than a map of where rotation becomes too low to sustain dynamo activity.

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