DISCUSSION OF THE CENTER OF MASS MOTION IN A SYSTEM WITH THREE DEGREES OF FREEDOM

2013 ◽  
Vol 22 (06) ◽  
pp. 1350043
Author(s):  
WERNER SCHEID

This paper considers the problem of the center of mass motion of three fermionic particles, e. g., equal nucleons (no spin), which can move only in the x-direction in the laboratory system. This system (with three degrees of freedom only) is transformed to a system where one coordinate is proportional to the center of mass coordinate. The center of mass moves in a harmonic oscillator potential. The basis set of wave functions is constructed with Hermite polynomials in part. As example we study the case of a quadratic intrinsic potential between the particles. The problem may be important for the motion of three nucleons in a crystal channel.

1996 ◽  
Vol 05 (04) ◽  
pp. 911-919
Author(s):  
J.C. GARREAU ◽  
D. WILKOWSKI ◽  
D. HENNEQUIN ◽  
V. ZEHNLÉ

This paper discusses a new scheme for generating quantum coherence between different degrees of freedom of an atom interacting with two modes of the electromagnetic field. The presence of quantum interference in a two-photon coupling between the ground state of the atom and the continuum through two quasi-resonant intermediate states induces selective ionization of the atoms for particular combinations of the different parameters characterizing the degrees of freedom of the system, leading to quantum coherence between the internal state, the center-of-mass motion of the atom, and the electromagnetic field. The application of this method to the selection of an atomic velocity class is discussed.


2013 ◽  
Vol 404 ◽  
pp. 244-249
Author(s):  
Rui Wang ◽  
Hao Zhang ◽  
Xian Sheng Li ◽  
Xue Lian Zheng ◽  
Yuan Yuan Ren

By establishing bus simplify coordinate system model and equivalent mechanical model, inertial forces and external forces are analyzed through vehicle lateral movement and vehicle's yaw motion and roll motion. Three degrees of freedom linear motion equation of vehicle is established taking into account lateral motion, yawing movement and rolling motion of vehicle and it can be solved by using method of state space equation. Vehicle dynamic characteristics are analyzed by using this method and programming with Matlab. Vehicle in steering wheel angle step response is analyzed under the conditions of different tire wheel cornering stiffness, moment of inertia, height of center of mass. The results show that increasing rear wheel cornering stiffness, reducing front wheel cornering stiffness and center of mass height, which can effectively improve stability of vehicle. Simulation results provide a theoretical basis and reference for the selection and design of vehicle.


2010 ◽  
Vol 7 (2) ◽  
pp. 1028-1033
Author(s):  
Baghdad Science Journal

An analytical expression for the charge density distributions is derived based on the use of occupation numbers of the states and the single particle wave functions of the harmonic oscillator potential with size parameters chosen to reproduce the observed root mean square charge radii for all considered nuclei. The derived expression, which is applicable throughout the whole region of shell nuclei, has been employed in the calculations concerning the charge density distributions for odd- of shell nuclei, such as and nuclei. It is found that introducing an additional parameters, namely and which reflect the difference of the occupation numbers of the states from the prediction of the simple shell model leads to obtain a remarkable agreement between the calculated and experimental results of the charge density distributions throughout the whole range of


1996 ◽  
Vol 11 (11) ◽  
pp. 891-898 ◽  
Author(s):  
N. GURAPPA ◽  
PRASANTA K. PANIGRAHI

An operator method is provided to generate an explicit set of complete eigenfunctions for the Calogero–Sutherland model, obtained earlier by Vacek, Okiji and Kawakami, through a special ansatz. We find the connection of the above basis set with the general eigenfunctions of this model and explicitly show that these states describe only the center-of-mass motion.


To understand how collective motion can develop in the shell-model framework it is necessary to study configuration interaction. With this in mind, group-theoretical methods are used to investigate the possible classification schemes for a number of nucleons in m xed configurations. One particular coupling scheme, which is associated with the degeneracy of a harmonic oscillator potential and which, in a following paper, will be shown to have collective properties is described in detail. The wave functions in this scheme are seen to be very similar to those resulting from an actual shell-model calculation with configurational mixing.


2011 ◽  
Vol 143-144 ◽  
pp. 355-359
Author(s):  
Wen Jun Lv ◽  
Xin Sheng Ge

In this paper, we study the attitude control problems based on model of spherical pendulum. Three degrees of freedom pendulum (3D pendulum) is a rigid body supported by a frictionless pivot. According to relative position of the center of mass and the fixed pivot without friction, the 3D rigid pendulum can be divided into two balanced attitudes, Hanging equilibrium and inverted equilibrium. For the axisymmetric 3D rigid pendulum, the axis of symmetry is equivalent to axis of inertia of rigid body, and angular velocity around the axis of symmetry is equal to zero, as a result, the 3D rigid pendulum can be equal to the spherical pendulum. According to the motion attitude of spherical pendulum, one control method based on passive theory is proposed in this paper, Firstly, we use the passive theory to research the equilibrium stability of spherical pendulum. Secondly, passive theory and the Lyapunov function are utilized to deduce the control law .Finally, the spherical pendulum reach asymptotically stable in equilibrium position.


1996 ◽  
Vol 11 (18) ◽  
pp. 1489-1495 ◽  
Author(s):  
P. ROY

It is shown that the two-anyon system in a harmonic oscillator potential and in a constant magnetic field admits certain q-deformed symmetry algebras realized over the space of wave functions of the respective systems.


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