Related papers: The Proton-Spin Crisis: another ABJ anomaly?
The Proca-Corben-Schwinger equations for a spin-1 particle with an anomalous magnetic moment are added by a term describing an electric dipole moment, then they are reduced to a Hamiltonian form, and finally they are brought to the…
Keywords (parts 1-4): metron / unified theory / wave particle duality / higher-dimensional gravity / solitons / Maxwell-Dirac-Einstein system / Standard Model / EPR paradox / Bell's theorem / arrow of time
The fundamental program in high energy spin physics focuses on the spin structure of the nucleon. The gluon and orbital angular momentum components of the nucleon spin are virtually unknown. The J_z=1/2 sum rule involves the integrated…
The inclusive A_1,p and hadron double-spin asymmetries A_p^pi+, A_p^pi-, A_p^K+, A_p^K- measured at COMPASS (CERN SPS) in deep-inelastic scattering of a polarized muon beam off a polarized NH_3 solid target are presented. The results have…
This article provides a unified introduction to the theory of electron and proton spin polarisation in storage rings and it provides a common starting point for the written versions of the four talks that I gave at Monterey
We show that the Bjorken sum rule for the first moment of the polarized nucleon structure function $g_1$ is not necessarily satisfied in QCD if the axial anomaly is taken into account. We argue that nonperturbative QCD effects should lead…
In this work we suggest a simple theoretical model of the proton able to effectively solve proton spin crisis. Within domain of applicability of this simple model proton consists only of two u quarks and one d quarks (two of which have spin…
The nucleon spin structure has been an active, exciting and intriguing subject of interest for the last three decades. Recent experimental data on nucleon spin structure at low to intermediate momentum transfers provide new information in…
We present a sample of results of our work to be published soon on Timelike Compton scattering off the proton, in the framework of the Generalized Parton Distributions formalism.
The part of the proton spin $\Sigma$ carried by $u, d, s$ quarks is calculated in the framework of the QCD sum rules in the external fields. The operators up to dimension 9 are accounted. An important contribution comes from the operator of…
For any inclusive reaction of the type $A_1({spin} 1/2)+ A_2({spin} 1/2) \to B + X$, we derive new positivity constraints on spin observables and study their implications for theoretical models in view, in particular, of accounting for…
The proton spin problem triggered by the EMC experiment and its present status are closely examined. Recent experimental and theoretical progresses and their implications are reviewed. It is pointed out that the sign of the sea-quark…
The longitudinal double spin asymmetries $A_1^p$ and the spin dependent structure function of the proton $g_1^p$ were extracted from COMPASS data in the region of low Bjorken scaling variable $x$ and low photon virtuality $Q^2$. The data…
In the first part of this dissertation, we study two different aspects of string phenomenology. First we discuss the complementary signals of low mass superstrings at the proposed electron-positron facilities (ILC and CLIC), in e+e- and…
I describe a few of the most exciting open questions in high energy spin physics. After a brief look at (g-2)_\mu and the muon electric dipole moment, I concentrate on QCD spin physics. Pressing questions include the interpretation of new…
CONTENTS: 1. Synopsis, 2. The MSSM Spectrum, 3. The Physical Parameters, 4. Higgs Boson Production and Decays, 5. SUSY Particle Production and Decays, 6. Experimental Bounds on SUSY Particle Masses, 7. References.
So far, the Standard Model of Elementary Particles has not succeeded getting a trustworthy account of the proton spin, which remains an enigma. This hindrance is known as the proton spin crisis, owing to the experimental evidence already…
The formulation of the Gerasimov-Drell-Hearn sum rule is revisited, showing its connection with other sum rules occurring in electron scattering and discussing the problem of its saturation, both from the theoretical and experimental point…
Expanding the results of [1], [2], [3], we demonstrate a network of algebraic connections between six well-known particle theories. These are the Spin(10) model, the Georgi-Glashow model, the Pati-Salam model, the Left-Right Symmetric…
Quantum statistical distributions for the partons provide a fair description of deep inelastic scattering data at $Q^2 = 3$ and $10 (GeV/c)^2$. The study of the polarized structure functions seems to suggest an alternative possible solution…