scholarly journals Lorentz structure of the vector part of matrix elements ofn↔ptransitions, caused by strong low-energy interactions and hypothesis of conservation of charged vector current

2018 ◽  
Vol 45 (2) ◽  
pp. 025004 ◽  
Author(s):  
A N Ivanov
Keyword(s):  
Vector Current ◽  
Low Energy ◽  
Matrix Elements ◽  
Lorentz Structure ◽  
Vector Part

scholarly journals BARYONS AS THREE-FLAVOR SOLITONS

1996 ◽  
Vol 11 (14) ◽  
pp. 2419-2544 ◽  
Author(s):  
HERBERT WEIGEL
Keyword(s):  
Symmetry Breaking ◽  
Vector Meson ◽  
Degrees Of Freedom ◽  
Magnetic Moments ◽  
Axial Vector ◽  
Vector Current ◽  
Bound State ◽  
Axial Vector Current ◽  
Flavor Symmetry ◽  
Matrix Elements

The description of baryons as soliton solutions of effective meson theories for three-flavor (up, down and strange) degrees of freedom is reviewed and the phenomenological implications are illuminated. In the collective approach the soliton configuration is equipped with baryon quantum numbers by canonical quantization of the coordinates describing the flavor orientation. The baryon spectrum resulting from exact diagonalization of the collective Hamiltonian is discussed. The prediction of static properties, such as the baryon magnetic moments and the Cabibbo matrix elements for semileptonic hyperon decays, are explored with regard to the influence of flavor symmetry breaking. In particular, the role of strange degrees of freedom in the nucleon is investigated for both the vector and axial vector current matrix elements. The latter are discussed extensively within the context of the proton spin puzzle. The influence of flavor symmetry breaking on the shape of the soliton is examined, and observed to cause significant deviations from flavor-covariant predictions on the baryon magnetic moments. Short range effects are incorporated by a chirally invariant inclusion of vector meson fields. These extensions are necessary for properly describing the singlet axial vector current and the neutron–proton mass difference. The effects of the vector meson excitations on baryon properties are also considered. The bound state description of hyperons and its generalization to baryons containing a heavy quark are illustrated. In the case of the Skyrme model a comparison is made between the collective quantization scheme and the bound state approach. Finally, the Nambu–Jona-Lasinio model is employed to demonstrate that hyperons can be described as solitons in a microscopic theory of the quark flavor dynamics. This is explained for both the collective and the bound state approaches to strangeness.

Low energy constraints on strange matrix-elements of the proton

1989 ◽  
Vol 223 (3-4) ◽  
pp. 439-444 ◽  
Author(s):  
Véronique Bernard ◽  
Ulf-G. Meiβner
Keyword(s):  
Low Energy ◽  
Matrix Elements ◽  
Energy Constraints

Current Algebras and Matrix Elements of the Axial-Vector Current

1966 ◽  
Vol 148 (4) ◽  
pp. 1405-1407 ◽  
Author(s):  
H. J. Lipkin ◽  
H. R. Rubinstein ◽  
S. Meshkov
Keyword(s):  
Axial Vector ◽  
Vector Current ◽  
Axial Vector Current ◽  
Matrix Elements ◽  
Current Algebras

scholarly journals Flavor anomalies from asymptotically safe gravity

2021 ◽  
Vol 81 (4) ◽  
Author(s):  
Kamila Kowalska ◽  
Enrico Maria Sessolo ◽  
Yasuhiro Yamamoto
Keyword(s):  
Hadron Collider ◽  
Planck Scale ◽  
Mass Range ◽  
Low Energy ◽  
Matrix Elements ◽  
Yukawa Couplings ◽  
Leptonic Decays ◽  
Scalar Leptoquark ◽  
S 100 ◽  
Gravity Driven

AbstractWe use the framework of asymptotically safe quantum gravity to derive predictions for scalar leptoquark solutions to the $$b\rightarrow s$$ b → s and $$b\rightarrow c$$ b → c flavor anomalies. The presence of an interactive UV fixed point in the system of gauge and Yukawa couplings imposes a set of boundary conditions at the Planck scale, which allows one to determine low-energy values of the leptoquark Yukawa matrix elements. As a consequence, the allowed leptoquark mass range can be significantly narrowed down. We find that a consistent gravity-driven solution to the $$b\rightarrow s$$ b → s anomalies predicts a leptoquark with the mass of 4–7 $$\,\mathrm {TeV}$$ TeV , entirely within the reach of a future hadron-hadron collider with $$\sqrt{s}=100\,\mathrm {TeV}$$ s = 100 TeV . Conversely, in the case of the $$b\rightarrow c$$ b → c anomalies the asymptotically safe gravity framework predicts a leptoquark mass at the edge of the current LHC bounds. Complementary signatures appear in flavor observables, namely the (semi)leptonic decays of B and D mesons and kaons.

scholarly journals A Nonlocal Potential Form for s-wave α - α Scattering

1998 ◽  
Vol 51 (1) ◽  
pp. 47
Author(s):  
M. T. Bennett ◽  
K. Amos
Keyword(s):  
Density Matrix ◽  
Low Energy ◽  
Nonlocal Interaction ◽  
Particle Interactions ◽  
Matrix Elements ◽  
Nonlocal Potential ◽  
S Wave ◽  
Α Phase ◽  
Potential Form ◽  
Energy Dependent

Low energy s-wave α–α phase shifts that agree well with the measured set have been extracted using a nonlocal interaction formed by folding (local real energy-dependent) nucleon-α–particle interactions with density matrix elements of the (projectile) α–particle. The resultant s-wave α–α interaction is energy dependent and nonlocal.

scholarly journals The Dual QCD @ Work: 2018

2018 ◽  
Vol 192 ◽  
pp. 00048
Author(s):  
Andrzej J. Buras
Keyword(s):  
Lattice Qcd ◽  
New Physics ◽  
Low Energy ◽  
Effective Theory ◽  
Matrix Elements ◽  
General Study ◽  
The Road ◽  
The Past ◽  
Recent Developments ◽  
Energy Approximation

The Dual QCD (DQCD) framework, based on the ideas of ’t Hooft and Witten, and developed by Bill Bardeen, Jean-Marc Gérard and myself in the 1980s is not QCD, a theory of quarks and gluons, but a successful low energy approximation of it when applied to K → ππ decays and K¯0 - K0 mixing. After years of silence, starting with 2014, this framework has been further developed in order to improve the SM prediction for the ratio ε'/ε, the ΔI = 1/2 rule and B^K. Most importantly, this year it has been used for the calculation of all K → ππ hadronic matrix elements of BSM operators which opened the road for the general study of ε'/ε in the context of the SM effective theory (SMEFT). This talk summarizes briefly the past successes of this framework and discusses recent developments which lead to a master formula for ε'/ε valid in any extension of the SM. This formula should facilitate the search for new physics responsible for the ε'/ε anomaly hinted by 2015 results from lattice QCD and DQCD.

scholarly journals Two-current correlations in the pion in the Nambu and Jona-Lasinio model

2020 ◽  
Vol 80 (10) ◽  
Author(s):  
Aurore Courtoy ◽  
Santiago Noguera ◽  
Sergio Scopetta
Keyword(s):  
High Energy ◽  
Low Energy ◽  
Matrix Elements ◽  
Lattice Data ◽  
Energy Matrix ◽  
Parton Distributions ◽  
Factorization Approximation ◽  
Lattice Result ◽  
Villars Regularization ◽  
Current Correlations

AbstractWe present an analysis of two-current correlations for the pion in the Nambu–Jona-Lasinio model, with Pauli–Villars regularization. We provide explicit expressions in momentum space for two-current correlations corresponding to the zeroth component of the vector Dirac bilinear in the quark vertices, which has been evaluated on the lattice, thinking to applications in a high energy framework, as a step towards the calculation of pion double parton distributions. The numerical results show a remarkable qualitative agreement with recent lattice data. The factorization approximation into one-body currents is discussed based on previous evaluation of the relevant low energy matrix elements in the Nambu–Jona-Lasinio model, confirming the lattice result.

scholarly journals CP violation, an experimental perspective

2005 ◽  
Vol 20 (14) ◽  
pp. 2975-2990 ◽  
Author(s):  
OWEN LONG
Keyword(s):  
Cp Violation ◽  
Electric Dipole ◽  
Dipole Moments ◽  
Low Energy ◽  
High Mass ◽  
Experimental Investigations ◽  
Matrix Elements ◽  
Electric Dipole Moments ◽  
Mixing Matrix ◽  
Near Future

I present a review of current and near-future experimental investigations of CP violation. In this review, I cover limits on particle electric dipole moments (EDMs) and CP violation studies in the K and B systems. The wealth of results from the new B factories provide impressive constraints on the CKM quark mixing matrix elements. Current and future measurements are focusing on processes dominated by loop diagrams, which probe physics at high mass scales in low-energy experiments.

Sign in / Sign up

Export Citation Format

Share Document