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Superfluid Quenching of the Moment of Inertia in a Strongly Interacting Fermi Gas  [PDF]
S. Riedl,E. R. Sanchez Guajardo,C. Kohstall,J. Hecker Denschlag,R. Grimm
Physics , 2009,
Abstract: We report on the observation of a quenched moment of inertia as resulting from superfluidity in a strongly interacting Fermi gas. Our method is based on setting the hydrodynamic gas in slow rotation and determining its angular momentum by detecting the precession of a radial quadrupole excitation. The measurements distinguish between the superfluid or collisional origin of hydrodynamic behavior, and show the phase transition.
Dynamical moment of inertia and quadrupole vibrations in rotating nuclei  [PDF]
R. G. Nazmitdinov,D. Almehed,F. Donau
Physics , 2001, DOI: 10.1103/PhysRevC.65.041307
Abstract: The contribution of quantum shape fluctuations to inertial properties of rotating nuclei has been analysed within the self-consistent one-dimensional cranking oscillator model. It is shown that in even-even nuclei the dynamical moment of inertia calculated in the mean field approximation is equivalent to the Thouless-Valatin moment of inertia calculated in the random phase approximation if and only if the self-consistent conditions for the mean field are fulfilled.
Role on Moment of Inertia and Vortex Dynamics for a Thin Rotating Plate  [PDF]
Yoshihiro Kubota, Osamu Mochizuki
World Journal of Mechanics (WJM) , 2013, DOI: 10.4236/wjm.2013.36028
Abstract:

In this study, we focused on the lift generation with a thin rotating plate. The objective of this study is to understand the appropriate shape and the role of vortex for rotating thin plate. We determined the shape of the plate through free-flight tests of paper strips and investigated the aerodynamic characteristics of the rotating plate with the selected shape. The rectangular plate with an aspect ratio 7 was relevant from moment of inertia and bending stress. An endplate on a wing tip increased the stability on the lateral vortex structure behind the rotating plate. Velocity field measurement by Particle Image Velocimetry (PIV) showed that the lift force was generated twice in a rotating cycle.

Gravitomagnetic London Moment in Rotating Supersolid $He^4$  [PDF]
Clovis Jacinto de Matos
Physics , 2007,
Abstract: Non classical rotational inertia observed in rotating supersolid $He^4$ can be accounted for by a gravitomagnetic London moment similar to the one recently reported in rotating superconductive rings.
Surface corrections to the shell-structure of the moment of inertia  [PDF]
D. V. Gorpinchenko,A. G. Magner,J. Bartel,J. P. Blocki
Physics , 2015,
Abstract: The moment of inertia for nuclear collective rotations is derived within a semiclassical approach based on the Inglis cranking and the Strutinsky shell-correction methods, improved by surface corrections within the non-perturbative periodic-orbit theory. For adiabatic (statistical-equilibrium) rotations it was approximated by the generalized rigid-body moment of inertia accounting for the shell corrections of the particle density. An improved phase-space trace formula allows to express the shell components of the moment of inertia more accurately in terms of the free-energy shell correction with their ratio evaluated within the extended Thomas-Fermi effective-surface approximation.
Finite temperature vortices in a rotating Fermi gas  [PDF]
S. N. Klimin,J. Tempere,N. Verhelst,M. V. Milo?evi?
Physics , 2015,
Abstract: Vortices and vortex arrays have been used as a hallmark of superfluidity in rotated, ultracold Fermi gases. These superfluids can be described in terms of an effective field theory for a macroscopic wave function representing the field of condensed pairs, analogous to the Ginzburg-Landau theory for superconductors. Here, we have established how rotation modifies this effective field theory, by rederiving it starting from the action of Fermi gas in the rotating frame of reference. In particular, we show that the moment of inertia that can be attributed to the pairs deviates from the naive expectation that it is twice the moment of inertia of the constituent fermions, which is only realized in the deep BEC regime. Then, we use our macroscopic wave function description to study vortices and the critical rotation frequencies to form them. Phase diagrams for vortex states are derived, and they are in good agreement with available results of the Bogoliubov -- De Gennes theory and with experimental data.
Moment of Inertia and Quadrupole Response Function of a Trapped Superfluid  [PDF]
Francesca Zambelli,Sandro Stringari
Physics , 2000, DOI: 10.1103/PhysRevA.63.033602
Abstract: We derive an explicit relationship between the moment of inertia and the quadrupole response function of an interacting gas confined in a harmonic trap. The relationship holds for both Bose and Fermi systems and is well suited to reveal the effects of irrotationality of the superfluid motion. Recent experimental results on the scissors mode are used to extract the value of the moment of inertia of a trapped Bose gas and to point out the deviations from the rigid value due to superfluidity.
Semiclassical shell-structure moment of inertia within the phase-space approach  [PDF]
D. V. Gorpinchenko,A. G. Magner,J. Bartel,J. P. Blocki
Physics , 2014,
Abstract: The moment of inertia for nuclear collective rotations was derived within the semiclassical approach based on the cranking model and the Strutinsky shell-correction method by using the non-perturbative periodic-orbit theory in the phase space variables. This moment of inertia for adiabatic (statistical-equilibrium) rotations can be approximated by the generalized rigid-body moment of inertia accounting for the shell corrections of the particle density. A semiclassical phase-space trace formula allows to express quite accurately the shell components of the moment of inertia in terms of the free-energy shell corrections for integrable and partially chaotic Fermi systems, in good agreement with the quantum calculations.
Simulation study of three-phase induction motor with variations in moment of inertia  [PDF]
K. S. Sandhu,Vivek Pahwa
Journal of Engineering and Applied Sciences , 2009,
Abstract: Transient performance of any electrical machine is greatly affected by sudden changes in its supply system, operating speed, shaft load including any variations in moment of inertia due to gear arrangement applications. D, q- axis modeling which is universally acceptable to determine such analysis may be adopted using stator reference frame/rotor reference frame/synchronously rotating reference frame. In this paper, rotor reference frame is used for the simulation study of three phase induction motor. MATLAB/SIMULINK based modeling is adopted to compare the transient performance of three-phase induction motor including main flux saturation with and without the moment of inertia (MOI) of the system attached to the motor. Simulated results have been compared and verified with experimental results on a test machine set-up. A close agreement between the simulated and experimental results proves the validity of proposed modeling.
The nuclear moment of inertia and spin distribution of nuclear levels  [PDF]
Y. Alhassid,G. F. Bertsch,L. Fang,S. Liu
Physics , 2005, DOI: 10.1103/PhysRevC.72.064326
Abstract: We introduce a simple model to calculate the nuclear moment of inertia at finite temperature. This moment of inertia describes the spin distribution of nuclear levels in the framework of the spin-cutoff model. Our model is based on a deformed single-particle Hamiltonian with pairing interaction and takes into account fluctuations in the pairing gap. We derive a formula for the moment of inertia at finite temperature that generalizes the Belyaev formula for zero temperature. We show that a number-parity projection explains the strong odd-even effects observed in shell model Monte Carlo studies of the nuclear moment of inertia in the iron region.
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