NUCLEI AS TOPOLOGICAL SOLITONS

The application of the Skyrme model to the construction of interaction and current operators for nuclear systems is reviewed. The long-range behaviors of these operators are found to agree with results of phenomenological meson theories based on effective chiral Lagrangians. The Skyrme model thus provides a compact method for obtaining long-range parts of such operators, consistent with the usual soft-pion theorems as well as with the requirement of current conservation. Predictions of the short-range parts of the operators remain uncertain due to difficulties in solving the equations of motion for the two-nucleon problem. The usual factorized ansatz for the soliton field of the two-nucleon system does not give sufficient accuracy at short range. The possibility of an improvement which would allow the construction of spin and isospin operators for the individual nucleons is discussed. Finally, the Skyrme model is discussed in the limit of large baryon number.

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Contributions of Three-body Overlap Effects to the Force Fields in CaF2-type Shell-model Lattices

Zeitschrift für Naturforschung A ◽

10.1515/zna-1972-8-906 ◽

1972 ◽

Vol 27 (8-9) ◽

pp. 1196-1210

Author(s):

Ø. Ra

Keyword(s):

Force Field ◽

Shell Model ◽

Long Range ◽

Short Range ◽

Equations Of Motion ◽

Exclusion Principle ◽

Electronic Charge ◽

Short Range Force ◽

Model Equations ◽

Three Body

Abstract Due to the exclusion principle the distribution of electronic charge in an ionic crystal differs from a superposition of free-ion charge densities even in the simple Heitler-London picture. This charge density deformation engenders three-body long-range forces the influence of which on lattice vibrations is not accounted for by the usual Kellermann matrix. To obtain a better separation of long-range from short-range forces in CaF2 , SrF2, and BaF2 , i. e. to avoid absorbing long-range interactions in an adjustable short-range force field, explicit formulae are derived for three-body contributions to the shell-model equations of motion. The additional dynamical matrices pertain to arbitrary wavelengths. In adding to the force field terms which are not purely volume dependent the present descirption of three-body forces is somewhat at variance with recent work on alkali halide dynamics. The deviation from pure volume dependence originates in overlap charges residing in internuclear regions.

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Structural basis of long-range to short-range synaptic transition in NHEJ

Nature ◽

10.1038/s41586-021-03458-7 ◽

2021 ◽

Author(s):

Siyu Chen ◽

Linda Lee ◽

Tasmin Naila ◽

Susan Fishbain ◽

Annie Wang ◽

...

Keyword(s):

Long Range ◽

Short Range ◽

Structural Basis

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Comparison of short-range order in irradiated dysprosium titanates

npj Materials Degradation ◽

10.1038/s41529-021-00165-6 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Roman Sherrod ◽

Eric C. O’Quinn ◽

Igor M. Gussev ◽

Cale Overstreet ◽

Joerg Neuefeind ◽

...

Keyword(s):

Long Range ◽

Short Range ◽

Structural Model ◽

Ion Irradiation ◽

Function Analysis ◽

Ion Beam ◽

Structural Response ◽

Heavy Ion ◽

Range Order ◽

Radiation Resistant

AbstractThe structural response of Dy2TiO5 oxide under swift heavy ion irradiation (2.2 GeV Au ions) was studied over a range of structural length scales utilizing neutron total scattering experiments. Refinement of diffraction data confirms that the long-range orthorhombic structure is susceptible to ion beam-induced amorphization with limited crystalline fraction remaining after irradiation to 8 × 1012 ions/cm2. In contrast, the local atomic arrangement, examined through pair distribution function analysis, shows only subtle changes after irradiation and is still described best by the original orthorhombic structural model. A comparison to Dy2Ti2O7 pyrochlore oxide under the same irradiation conditions reveals a different behavior: while the dysprosium titanate pyrochlore is more radiation resistant over the long-range with smaller degree of amorphization as compared to Dy2TiO5, the former involves more local atomic rearrangements, best described by a pyrochlore-to-weberite-type transformation. These results highlight the importance of short-range and medium-range order analysis for a comprehensive description of radiation behavior.

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An explicit construction of the dimension-9 operator basis in the standard model effective field theory

Journal of High Energy Physics ◽

10.1007/jhep11(2020)152 ◽

2020 ◽

Vol 2020 (11) ◽

Author(s):

Yi Liao ◽

Xiao-Dong Ma

Keyword(s):

Field Theory ◽

Standard Model ◽

Effective Field Theory ◽

Equations Of Motion ◽

Baryon Number ◽

Explicit Construction ◽

Effective Field ◽

Starting Point ◽

The Standard Model ◽

Symmetry Relations

Abstract We investigate systematically dimension-9 operators in the standard model effective field theory which contains only standard model fields and respects its gauge symmetry. With the help of the Hilbert series approach to classifying operators according to their lepton and baryon numbers and their field contents, we construct the basis of operators explicitly. We remove redundant operators by employing various kinematic and algebraic relations including integration by parts, equations of motion, Schouten identities, Dirac matrix and Fierz identities, and Bianchi identities. We confirm counting of independent operators by analyzing their flavor symmetry relations. All operators violate lepton or baryon number or both, and are thus non-Hermitian. Including Hermitian conjugated operators there are $$ {\left.384\right|}_{\Delta B=0}^{\Delta L=\pm 2}+{\left.10\right|}_{\Delta B=\pm 2}^{\Delta L=0}+{\left.4\right|}_{\Delta B=\pm 1}^{\Delta L=\pm 3}+{\left.236\right|}_{\Delta B=\pm 1}^{\Delta L=\mp 1} $$ 384 Δ B = 0 Δ L = ± 2 + 10 Δ B = ± 2 Δ L = 0 + 4 Δ B = ± 1 Δ L = ± 3 + 236 Δ B = ± 1 Δ L = ∓ 1 operators without referring to fermion generations, and $$ {\left.44874\right|}_{\Delta B=0}^{\Delta L=\pm 2}+{\left.2862\right|}_{\Delta B=\pm 2}^{\Delta L=0}+{\left.486\right|}_{\Delta B=\pm 1}^{\Delta L=\pm 3}+{\left.42234\right|}_{\Delta B=\mp 1}^{\Delta L=\pm 1} $$ 44874 Δ B = 0 Δ L = ± 2 + 2862 Δ B = ± 2 Δ L = 0 + 486 Δ B = ± 1 Δ L = ± 3 + 42234 Δ B = ∓ 1 Δ L = ± 1 operators when three generations of fermions are referred to, where ∆L, ∆B denote the net lepton and baryon numbers of the operators. Our result provides a starting point for consistent phenomenological studies associated with dimension-9 operators.

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SHORT-RANGE AND LONG-RANGE ORDER OF TITANIUM IN Ti1+xS2

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1977738 ◽

1977 ◽

Vol 38 (C7) ◽

pp. C7-202-C7-206 ◽

Cited By ~ 3

Author(s):

R. MORET ◽

M. HUBER ◽

R. COMÈS

Keyword(s):

Long Range ◽

Short Range ◽

Range Order ◽

Long Range Order

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Short range smectic order driving long range nematic order: example of cuprates

Scientific Reports ◽

10.1038/srep19678 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

R. S. Markiewicz ◽

J. Lorenzana ◽

G. Seibold ◽

A. Bansil

Keyword(s):

Long Range ◽

Short Range ◽

Nematic Order

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ANDERSON LOCALIZATION FOR A MULTIDIMENSIONAL MODEL INCLUDING LONG RANGE POTENTIALS AND DISPLACEMENTS

Reviews in Mathematical Physics ◽

10.1142/s0129055x02001193 ◽

2002 ◽

Vol 14 (03) ◽

pp. 273-302 ◽

Cited By ~ 3

Author(s):

HERIBERT ZENK

Keyword(s):

Long Range ◽

Anderson Model ◽

Anderson Localization ◽

Short Range ◽

Energy Interval ◽

Multidimensional Model ◽

Short Summary

We give a short summary on how to combine and extend results of Combes and Hislop [2] (short range Anderson model with additional displacements), Kirsch, Stollmann and Stolz [13] and [14] (long range Anderson model without displacements) to get localization in an energy interval above the infimum of the almost sure spectrum for a continuous multidimensional Anderson model including long range potentials and displacements.

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