Related papers: Weak radius of the proton
As it involves the lightest physical states excited from the vacuum by the vector quark current, near-threshold $\rho^0$ photoproduction is considered a possible way to research the proton radius and the absolute value of the scattering…
The high precision parity violating electron scattering experiments PREX and QWEAK are sensitive to radiative corrections. In this paper we introduce the PREX experiment that measures the neutron radius of $^{208}$Pb and discuss coulomb…
An effective field theory is used to give a model-independent description of Compton scattering at energies comparable to the pion mass. The amplitudes for scattering on the proton and the deuteron, calculated to fourth order in small…
This note is motivated by preparations of a new $ep$ elastic scattering experiment in the low transfer momentum region to be carried out in the 720 MeV electron beam of the Mainz Microtron MAMI. This experiment will use an innovative method…
Weak values of the spin operator Sz of massive particles, more precisely neutrons, have been experimentally determined by applying a novel measurement scheme. This is achieved by coupling the neutron's spin weakly to its spatial degree of…
We report on the contributions to the nucleon weak magnetic and electric form factors arising from isospin-breaking form factors. The relativized quark model used in the calculations includes isospin impurities in the large basis nucleon…
We calculate the proton distribution function due to heating by subsonic (Alfvenic) turbulence in a weakly magnetized collisionless plasma. The distribution function is nonthermal. For non-relativistic energies, it is an exponential of the…
New precise results of a measurement of the elastic electron-proton scattering cross section performed at the Mainz Microtron MAMI are presented. About 1400 cross sections were measured with negative four-momentum transfers squared up to…
In this thesis, which is in the field of few-body systems, I am studying low-energy electro-weak interactions in light nuclear systems whose number of nucleons, $A$, is smaller than 4 ({\it i.e.,} $d$, $^3$H, $^3$He), where the main purpose…
We describe a measurement of the charge asymmetry of leptons from W boson decays in the rapidity range 0<|y_l|<2.5 using W --> enu, munu events from 110+/-7 pb^{-1}of data collected by the CDF detector during 1992-95. The asymmetry data…
In this paper we present a concise overview of our recent results concerning the electric potential distribution around a small charged particle in weakly ionized plasmas. A number of different effects which influence plasma screening…
We consider the dispersion correction to elastic parity violating electron-proton scattering due to \gammaZ exchange. In a recent publication, this correction was reported to be substantially larger than the previous estimates. In this…
The weak bosons are bound states of two fermions and their antiparticles, denoted as haplons. The confinement scale of the associated gauge group SU(2) is of the order of 0.5 TeV. Besides the weak bosons there exist also new bosons, an…
The proton size has been found, with a $6\,\sigma$ statistical significance, to be larger by 4% when it is measured relatively to the electron than to the muon [Pohl2010,Antognini2013]. We solve this proton radius puzzle by accounting for…
The proton is one of the main building blocks of all visible matter in the universe. Among its intrinsic properties are its electric charge, mass, and spin. These emerge from the complex dynamics of its fundamental constituents, quarks and…
The relatively small fraction of the spin of the proton carried by its quarks presents a major challenge to our understanding of the strong interaction. Traditional efforts to explore this problem have involved new and imaginative…
The X-ray cascade from antiprotonic atoms was studied for 208Pb and 209Bi. Widths and shifts of the levels due to the strong interaction were determined. Using modern antiproton-nucleus optical potentials the neutron densities in the…
The most precise measurement to date of the W boson hadronic decay branching fraction ratio $R_\mathrm{c}^\mathrm{W}$ = $\mathcal{B}$(W $\to$ cq) / $\mathcal{B}$(W $\to$ $\mathrm{q\bar{q}'}$) is presented. The measurement is based on a…
A new approach to determine the LHC luminosity is investigated. Instead of employing the proton-proton luminosity measurement, we suggest to measure directly the parton-parton luminosity. It is shown that the electron and muon…
We show that the value of the proton mass depends on each bound state of muonic or electronic hydrogen atom. The charged particle bound to the proton produces magnetic field inside the proton. This makes a change to the amount of chiral…