Related papers: Proton polarizabilities: status, relevance, prospe…
An introduction to the methods and ideas of Chiral Perturbation Theory is presented in this talk. The discussion is illustrated with some phenomenological predictions that can be compared with available experimental results.
In this talk, I review recent developments in perturbative QCD and their applications to collider physics.
We give an overview of the current status of investigations of the polarization of gluons in the nucleon. We describe some of the physics of the spin-dependent gluon parton distribution and its phenomenology in high-energy polarized…
The threshold region for processes of hadronic and nuclear interactions is very interesting for a theoretical as well as an experimental point of view. In this region one can apply different physical methods, starting from classical current…
I summarize the dispersion-theoretical analysis of the nucleon electromagnetic form factors. Special emphasis is given on the extraction of the proton charge radius and its relatives, the proton magnetic radius as well as the neutron…
In this talk I present a summary of some of the discussions at the conference on various topics in Photon physics, selected with a view to give a theorist's perspective, of the current status and future prospects, of the developments in the…
Considerable progress has been made in our knowledge of the spin distribution within the proton. The recently measured limits on polarized gluons in the proton suggest polarized gluons contribute very modestly to the proton spin. We will…
In this short review article, we consider some aspects of the spin-polaron concept as they relate to high-Tc superconductivity. The article is intended to be an overview in which a flavor of the research on spin polarons is given.
The spin physics parallel sessions at this workshop made a critical review of the physics potential of future experiments on polarized nucleons, with an emphasis on the potential impact of polarized electron-proton collisions at HERA. A…
Proton spin is investigated in chiral effective field theory through an examination of the singlet axial charge, $a_0$, and the two non-singlet axial charges, $a_3$ and $a_8$. Finite-range regularization is considered as it provides an…
The extremely precise extraction of the proton radius by Pohl et al. from the measured energy difference between the 2P and 2S states of muonic hydrogen disagrees significantly with that extracted from electronic hydrogen or elastic…
The contribution of strange sea quarks to the proton mass and spin, as well as the related pion-nucleon sigma term, are briefly revisited, in the light of new experimental and lattice results. Also the predictions of chiral perturbation…
Proton decay is a hypothetical form of particle decay in which protons are assumed to decay into lighter particles. This form of decay has yet to be detected. In this contribution to the proceedings of Neutrino 2022, we review the current…
I discuss recent progress in our understanding of the pi pi scattering amplitude at low energy thanks to the combined use of chiral perturbation theory and dispersion relations. I also comment on the criticism raised by Pelaez and Yndurain…
Nucleons (protons and neutrons) are the building blocks of atomic nuclei, and are responsible for more than 99\% of the visible matter in the universe. Despite decades of efforts in studying its internal structure, there are still a number…
The issue of consistent power counting in baryon chiral perturbation theory is revisited.
We determine the root-mean-square proton charge radius, $R_{\rm p}$, from a fit to low-$Q^2$ electron-proton elastic scattering cross section data with the higher moments fixed (within uncertainties) to the values predicted by chiral…
As guideline for forthcoming experiments, we present predictions from Chiral Effective Field Theory for polarized cross sections in low energy Compton scattering for photon energies below 170 MeV, both on the proton and on the neutron.…
The Modern Theory of Polarization, which rigorously defines the spontaneous electric polarization of a periodic solid and provides a recipe for its computation in electronic structure codes, transformed our understanding of ferroelectricity…
Two groups, ours (Mainz) and Bochum, have recently been re-evaluating the spin polarizabilities and spin structure functions at low $Q$, using the baryon chiral perturbation theory (B$\chi$PT), the manifestly-covariant counterpart of the…