scholarly journals On the extraction of zero momentum form factors on the lattice

2012 ◽  
Vol 718 (2) ◽  
pp. 589-596 ◽  
Author(s):  
G.M. de Divitiis ◽  
R. Petronzio ◽  
N. Tantalo
Keyword(s):  
Form Factors ◽  
Zero Momentum

scholarly journals On the zero-crossing of the three-gluon Green’s function from lattice simulations

2018 ◽  
Vol 175 ◽  
pp. 12012 ◽  
Author(s):  
Andreas Athenodorou ◽  
Philippe Boucaud ◽  
Feliciano de Soto ◽  
José Rodríguez-Quintero ◽  
Savvas Zafeiropoulos
Keyword(s):  
Green’S Function ◽  
Green's Function ◽  
Large Volume ◽  
Form Factors ◽  
Tree Level ◽  
Zero Crossing ◽  
Zero Momentum ◽  
Made In

We report on some efforts recently made in order to gain a better understanding of some IR properties of the 3-point gluon Green’s function by exploiting results from large-volume quenched lattice simulations. These lattice results have been obtained by using both tree-level Symanzik and the standard Wilson action, in the aim of assessing the possible impact of effects presumably resulting from a particular choice for the discretization of the action. The main resulting feature is the existence of a negative log-aritmic divergence at zero-momentum, which pulls the 3-gluon form factors down at low momenta and, consequently, yields a zero-crossing at a given deep IR momentum. The results can be correctly explained by analyzing the relevant Dyson-Schwinger equations and appropriate truncation schemes.

scholarly journals Two-photon exchange in leptophilic dark matter scenarios

2021 ◽  
Vol 2021 (12) ◽  
Author(s):  
Raghuveer Garani ◽  
Federico Gasparotto ◽  
Pierpaolo Mastrolia ◽  
Henrik J. Munch ◽  
Sergio Palomares-Ruiz ◽  
...  
Keyword(s):  
Dark Matter ◽  
Momentum Transfer ◽  
Direct Detection ◽  
Form Factors ◽  
Scalar Particle ◽  
Analytical Form ◽  
Photon Exchange ◽  
Two Photon ◽  
Zero Momentum ◽  
Pseudo Scalar

Abstract In leptophilic scenarios, dark matter interactions with nuclei, relevant for direct detection experiments and for the capture by celestial objects, could only occur via loop-induced processes. If the mediator is a scalar or pseudo-scalar particle, which only couples to leptons, the dominant contribution to dark matter-nucleus scattering would take place via two-photon exchange with a lepton triangle loop. The corresponding diagrams have been estimated in the literature under different approximations. Here, we present new analytical calculations for one-body two-loop and two-body one-loop interactions. The two-loop form factors are presented in closed analytical form in terms of generalized polylogarithms up to weight four. In both cases, we consider the exact dependence on all the involved scales, and study the dependence on the momentum transfer. We show that some previous approximations fail to correctly predict the scattering cross section by several orders of magnitude. Moreover, we quantitatively show that form factors in the range of momentum transfer relevant for local galactic dark matter, can be significantly smaller than their value at zero momentum transfer, which is the approach usually considered.

scholarly journals Determining the Kl3 form factors directly at zero momentum transfer

2010 ◽  
Author(s):  
James Zanotti ◽  
Peter A. Boyle ◽  
Andreas Juttner ◽  
J. M. Flynn ◽  
Chris Kelly ◽  
...  
Keyword(s):  
Momentum Transfer ◽  
Form Factors ◽  
Zero Momentum

scholarly journals Electromagnetic and gravitational form factors in simulated QED and Yukawa model

2014 ◽  
Vol 29 (24) ◽  
pp. 1450118 ◽  
Author(s):  
Narinder Kumar ◽  
Harleen Dahiya
Keyword(s):  
Quantum Electrodynamics ◽  
Light Cone ◽  
Form Factors ◽  
Bound State ◽  
Momentum Tensor ◽  
Yukawa Model ◽  
Pauli Form Factor ◽  
Fock Representation ◽  
Fock State ◽  
Zero Momentum

The light-cone Fock state representation of composite systems has a number of remarkable properties and for systems such as hadrons they have exact representation for angular momentum, energy–momentum tensor. We investigate the electromagnetic and gravitational form factors with zero momentum transfer in Quantum Electrodynamics (QED) and Yukawa theory. To improve the convergence near the end points of x qualitatively as well as to check the consistency of the model, we differentiate the wave function w.r.t. bound state mass. We test the behavior of the anomalous gravitomagnetic moment, which follows directly from the Lorentz boost properties of the light-cone Fock representation, for the simulated model as well as the Yukawa model. We also discuss the Pauli form factor obtained from the spin-flip matrix element.

scholarly journals D meson semileptonic form factors at zero momentum transfer in 2+1+1 flavor lattice QCD

2016 ◽  
Author(s):  
Thomas Primer ◽  
Doug Toussaint ◽  
Claude Bernard ◽  
Javad Komijani ◽  
Carleton DeTar ◽  
...  
Keyword(s):  
Lattice Qcd ◽  
Momentum Transfer ◽  
D Meson ◽  
Form Factors ◽  
Zero Momentum

THE STRUCTURE OF 6Li AND ITS COULOMB FORM FACTORS

1971 ◽  
Vol 32 (C5) ◽  
pp. C5b-269-C5b-270
Author(s):  
Kuniharu Kubodera
Keyword(s):  
Form Factors
Sign in / Sign up

Export Citation Format

Share Document