3-D structure of the Glasma initial state: Breaking boost-invariance by collisions of extended shock waves in classical Yang-Mills theory

S. Schlichting; P. Singh

doi:10.1103/physrevd.103.014003

Induction of Highly Dynamic Shock Waves in Machining Processes with Multiple Loads and Short Tool Impacts

Applied Sciences ◽

10.3390/app9112293 ◽

2019 ◽

Vol 9 (11) ◽

pp. 2293 ◽

Cited By ~ 1

Author(s):

Andreas Tausendfreund ◽

Dirk Stöbener ◽

Andreas Fischer

Keyword(s):

Shock Waves ◽

High Speed ◽

Short Pulse ◽

Milling Process ◽

Manufacturing Processes ◽

Speckle Photography ◽

Machining Processes ◽

Initial State ◽

Multiple Loads ◽

Measurement Results

In order to study the mechanical loads of a workpiece in manufacturing processes such as single-tooth milling, in-process measurements of workpiece deformations are required. To enable the resolution of shock waves due to the mechanical impact of the tool, a novel measurement system based on speckle photography is introduced to measure the dynamic deformations and strains with a high temporal and spatial resolution. The measurement results indicate deformations and strains propagating through the workpiece with the speed of sound triggered by the tool impact (i.e., the tool impact is shown to induce shock waves during milling). Finite element simulations of the workpiece behavior are performed in addition, which support the experimental findings. In the considered case, the dynamic excitation subsides after 300 ms. Hence, in processes with even shorter cyclic multiple loads, the tool encounters an already excited initial state during machining, which needs to be taken into account when precisely modeling the milling process and the resulting workpiece quality. Finally, the measurement results demonstrate that speckle photography in combination with modern high-speed cameras and compact short-pulse lasers provides a deeper understanding of individual manufacturing processes.

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RESTRICTED CLASS OF COLLIDING EINSTEIN–YANG–MILLS PLANE WAVES

International Journal of Modern Physics A ◽

10.1142/s0217751x09046084 ◽

2009 ◽

Vol 24 (30) ◽

pp. 5579-5585 ◽

Cited By ~ 1

Author(s):

OZAY GURTUG ◽

MUSTAFA HALILSOY

Keyword(s):

Black Hole ◽

Shock Waves ◽

Linear Polarization ◽

Plane Waves ◽

Restricted Class ◽

Yang Mills ◽

Newman Black Hole ◽

Long Time ◽

Simple Class

By gauging an Abelian electromagnetic solution through a non-Abelian transformation and in accordance with a theorem proved long time ago, we construct a simple class of colliding Einstein–Yang–Mills plane waves. The solution is isometric to the Wu–Yang charged Kerr–Newman black hole and shares much of the properties satisfied by colliding Einstein–Maxwell plane waves. In the linear polarization limit with unit degenerate charge it reduces to the Bell–Szekeres solution for colliding em shock waves.

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Collinear electroweak radiation in antenna parton showers

The European Physical Journal C ◽

10.1140/epjc/s10052-020-08510-w ◽

2020 ◽

Vol 80 (10) ◽

Author(s):

Ronald Kleiss ◽

Rob Verheyen

Keyword(s):

Vector Boson ◽

Electroweak Theory ◽

Initial State ◽

Final State ◽

Yang Mills ◽

Spin Effects ◽

Vector Bosons ◽

Lhc Physics ◽

Electroweak Sector ◽

Preliminary Description

AbstractWe present a first implementation of collinear electroweak radiation in the Vincia parton shower. Due to the chiral nature of the electroweak theory, explicit spin dependence in the shower algorithm is required. We thus use the spinor-helicity formalism to compute helicity-dependent branching kernels, taking special care to deal with the gauge relics that may appear in computation that involve longitudinal polarizations of the massive electroweak vector bosons. These kernels are used to construct a shower algorithm that includes all possible collinear final-state electroweak branchings, including those induced by the Yang–Mills triple vector boson coupling and all Higgs couplings, as well as vector boson emissions from the initial state. We incorporate a treatment of features particular to the electroweak theory, such as the effects of bosonic interference and recoiler effects, as well as a preliminary description of the overlap between electroweak branchings and resonance decays. Some qualifying results on electroweak branching spectra at high energies, as well as effects on LHC physics are presented. Possible future improvements are discussed, including treatment of soft and spin effects, as well as issues unique to the electroweak sector.

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Tensile Failure of 55-Nitinol Wire

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100113858 ◽

1975 ◽

Vol 33 ◽

pp. 46-47

Author(s):

F. I. Grace

Keyword(s):

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect ◽

Stoichiometric Composition ◽

Tensile Failure ◽

Initial State ◽

Initial Shape ◽

Nitinol Wire ◽

Cscl Type ◽

Shear Transformation

An interest in NiTi alloys with near stoichiometric composition (55 NiTi) has intensified since they were found to exhibit a unique mechanical shape memory effect at the Naval Ordnance Laboratory some twelve years ago (thus refered to as NITINOL alloys). Since then, the microstructural mechanisms associated with the shape memory effect have been investigated and several interesting engineering applications have appeared.The shape memory effect implies that the alloy deformed from an initial shape will spontaneously return to that initial state upon heating. This behavior is reported to be related to a diffusionless shear transformation which takes place between similar but slightly different CsCl type structures.

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Investigation of shock-wave deformation history from recovered structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143754 ◽

1986 ◽

Vol 44 ◽

pp. 434-435

Author(s):

M.A. Mogilevsky ◽

L.S. Bushnev

Keyword(s):

Shock Wave ◽

Plastic Deformation ◽

Dislocation Density ◽

Shock Waves ◽

Shock Front ◽

Single Crystals ◽

Residual Deformation ◽

Deformation Structure ◽

Deformation History ◽

Deformation Velocity

Single crystals of Al were loaded by 15 to 40 GPa shock waves at 77 K with a pulse duration of 1.0 to 0.5 μs and a residual deformation of ∼1%. The analysis of deformation structure peculiarities allows the deformation history to be re-established.After a 20 to 40 GPa loading the dislocation density in the recovered samples was about 1010 cm-2. By measuring the thickness of the 40 GPa shock front in Al, a plastic deformation velocity of 1.07 x 108 s-1 is obtained, from where the moving dislocation density at the front is 7 x 1010 cm-2. A very small part of dislocations moves during the whole time of compression, i.e. a total dislocation density at the front must be in excess of this value by one or two orders. Consequently, due to extremely high stresses, at the front there exists a very unstable structure which is rearranged later with a noticeable decrease in dislocation density.

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