Determination of the effective transverse coherence of the neutron wave packet as employed in reflectivity investigations of condensed-matter structures. II. Analysis of elastic scattering using energy-gated wave packets with an application to neutron reflection from ruled gratings

The mode peaks in frequency domain of vibration signal are strongly interfered by strong noise, causing the inaccuracy mode parameters. According to this situation, this paper comes up with the thought of mode-peak segmentation based on the spectral clustering algorithm. First, according to the concept of wave packet, the amplitude-frequency of vibration signal is divided into wave packets. Taking each wave packet as a sample of clustering algorithm, the spectral clustering algorithm is used to classify these wave packets. The amplitude-frequency curve of a mode peak becomes a big wave packet in macroscopic. The experiment to simulation signals indicates that this spectral clustering algorithm could accord with the macroscopic observation of mode segmentation effectively, and has outstanding performance especially in strong noise.

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Spin-orbit states of neutron wave packets

Physical Review A ◽

10.1103/physreva.94.013605 ◽

2016 ◽

Vol 94 (1) ◽

Cited By ~ 7

Author(s):

Joachim Nsofini ◽

Dusan Sarenac ◽

Christopher J. Wood ◽

David G. Cory ◽

Muhammad Arif ◽

...

Keyword(s):

Wave Packets ◽

Spin Orbit ◽

Neutron Wave

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Spin-Orbit Entanglement in Time Evolution of Radial Wave Packets in Hydrogenic Systems

Open Systems & Information Dynamics ◽

10.1007/s11080-004-6632-4 ◽

2004 ◽

Vol 11 (04) ◽

pp. 401-409

Author(s):

Marcin Turek ◽

Piotr Rozmej

Keyword(s):

Wave Packet ◽

Time Evolution ◽

Time Scale ◽

Degrees Of Freedom ◽

Wave Packets ◽

Characteristic Time Scale ◽

Radial Wave ◽

Mean Values ◽

Breathing Motion ◽

Wave Packet Revival

Time evolution of radial wave packets built from the eigenstates of Dirac equation for a hydrogenic system is considered. Radial wave packets are constructed from the states of different n quantum numbers and the same lowest angular momentum. In general they exhibit a kind of breathing motion with dispersion and (partial) revivals. Calculations show that for some particular preparations of the wave packet one can observe interesting effects in spin motion, coming from inherent entanglement of spin and orbital degrees of freedom. These effects manifest themselves through some oscillations in the mean values of spin operators and through changes of spatial probability density carried by upper and lower components of the wave function. It is also shown that the characteristic time scale of predicted effects (called T ls ) is much smaller for radial wave packets than in other cases, reaching values comparable to (or even less than) the time scale for the wave packet revival.

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ACCELERATION OF PARTICLES BY THE FIELDS OF WAVE PACKETS

10.46813/2019-124-043 ◽

2019 ◽

pp. 43-46

Author(s):

V.А. Buts ◽

V.V. Kuzmin ◽

A.P. Tolstoluzhsky

Keyword(s):

Wave Packet ◽

Wave Packets ◽

Dynamic Chaos ◽

Acceleration Of Particles ◽

Nonlinear Resonances ◽

Dynamics Of Particles

The dynamics of particles in the field of a wave packet excited in a plasma is considered. The conditions are found under which such dynamics is regular, and when it becomes chaotic. It was found that the well-known (phenomenological) criterion for the emergence of dynamic chaos − the criterion for overlapping Chirikov nonlinear resonances − requires careful use.

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Excitation Of Localized Wave Packet In 3d Supersonic Boundary Layer

Siberian Journal of Physics ◽

10.54362/1818-7919-2017-12-1-57-65 ◽

2017 ◽

Vol 12 (1) ◽

pp. 57-65

Author(s):

Alex Yatskih ◽

Marina Rumenskikh ◽

Yuri Yermolaev ◽

Aleksandr Kosinov ◽

Nikolay Semionov ◽

...

Keyword(s):

Boundary Layer ◽

Wave Packet ◽

Wave Packets ◽

Leading Edge ◽

Supersonic Boundary Layer ◽

Swept Wing ◽

Sweep Angle ◽

Asymmetric Shape ◽

Pulse Electric ◽

Pulse Electric Discharge

The results of experimental study of excitation of localized in time and space controlled disturbances (wave packets) in a supersonic swept-wing boundary layer are presented. The experiments were performed at Mach number M = 2 on the model of wing with a lenticular profile and a 40 degrees sweep angle of the leading edge at zero angle of attack. Wave packets were generated by a pulse electric discharge on the surface of the model. A structure of controlled wave packet was studied. It was found that the wave packet has an asymmetric shape. Comparison with the case of twodimensional boundary layer was done.

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