Measuring Proton Spin Polarizabilities with Polarized Compton Scattering

Measuring Proton Spin Polarizabilities with Polarized Compton Scattering PDF Author: Philippe Paul Martel
Publisher:
ISBN:
Category : Compton effect
Languages : en
Pages : 208

Get Book Here

Book Description

Measuring Proton Spin Polarizabilities with Polarized Compton Scattering

Measuring Proton Spin Polarizabilities with Polarized Compton Scattering PDF Author: Philippe Paul Martel
Publisher:
ISBN:
Category : Compton effect
Languages : en
Pages : 208

Get Book Here

Book Description


Proton Spin Polarizabilities from Polarized Compton Scattering

Proton Spin Polarizabilities from Polarized Compton Scattering PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 15203

Get Book Here

Book Description
Polarized Compton scattering off the proton is studied within the framework of subtracted dispersion relations for photon energies up to 300 MeV. As a guideline for forthcoming experiments, we focus the attention on the role of the proton's spin polarizabilities and investigate the most favorable conditions to extract them with a minimum of model dependence. We conclude that a complete separation of the four spin polarizabilities is possible, at photon energies between threshold and the $\Delta(1232)$ region, provided one can achieve polarization measurements with an accuracy of a few percent.

Extracting the Proton Spin Polarizabilities Using Compton Scattering

Extracting the Proton Spin Polarizabilities Using Compton Scattering PDF Author: Robert M. D. Materi
Publisher:
ISBN:
Category : Polarizability (Electricity)
Languages : en
Pages : 88

Get Book Here

Book Description


MEASUREMENT OF THE GENERALIZED POLARIZABILITIES OF THE PROTON IN VIRTUAL COMPTON SCATTERING

MEASUREMENT OF THE GENERALIZED POLARIZABILITIES OF THE PROTON IN VIRTUAL COMPTON SCATTERING PDF Author: Ruonan Li
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

Get Book Here

Book Description
Understanding how the visible matter in the universe arises from its elementary quark andgluon constituents is a central question for science. The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state. A fundamental property of the proton involves the system's response to an external electromagnetic (EM) field. It is characterized by the EM polarizabilities that describe how easily the charge and magnetization distributions inside the system are distorted by the EM field. When the polarizabilities are generalized to finite momentum transfer, their Fourier transform can map out the spatial distribution of the polarization densities in a proton subject to an EM field. This thesis focuses on the measurement of the proton generalized polarizabilities (GPs) at low four-momentum transfer in experimental Hall C at the Thomas Jefferson National Accelerator Facility (TJNAF). Among the six independent GPs, we will focus on the electric (aE1) and the magnetic (bM1) scalar GPs. The GPs can be accessed through measurements of the Virtual Compton Scattering reaction, by replacing the incoming real photon of the Compton scattering process with a space-like virtual photon. The outgoing real photon provides the EM perturbation to the system. In addition, the Dispersion Relation Formalism is used for generalized polarizability extraction. In this work, the two scalar GPs measured with unprecedented precision, and the measurements help explore a momentum transfer region where an anomalous enhancement of the electric GP that contradicts the predictions of nuclear theory has been observed.

Measurement of Generalized Polarizabilities of the Proton by Virtual Compton Scattering

Measurement of Generalized Polarizabilities of the Proton by Virtual Compton Scattering PDF Author: Jure Beričič
Publisher:
ISBN:
Category :
Languages : en
Pages : 144

Get Book Here

Book Description


Measurement of the Generalized Polarizabilities of the Proton by Virtual Compton Scattering at MAMI and Q 2

Measurement of the Generalized Polarizabilities of the Proton by Virtual Compton Scattering at MAMI and Q 2 PDF Author: Loup Correa
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

Get Book Here

Book Description


Compton Scattering

Compton Scattering PDF Author: Frank Wissmann
Publisher: Springer Science & Business Media
ISBN: 9783540407423
Category : Science
Languages : en
Pages : 170

Get Book Here

Book Description
A comprehensive summary of experiments on Compton scattering from the proton and neutron performed at the electron accelerator MAMI. The experiments cover a photon energy range from 30 MeV to 500 MeV. The reader is introduced to the theoretical concepts of Compton scattering, followed by a description of the experiments on the proton, their analysis and results.

Measurement of the Generalized Polarizabilities of the Proton in Virtual Compton Scattering at Q2

Measurement of the Generalized Polarizabilities of the Proton in Virtual Compton Scattering at Q2 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Virtual Compton Scattering is studied at the Thomas Jefferson National Accelerator Facility in the energy domain below pion threshold and in the Delta(1232) resonance region. The data analysis is based on the Dispersion Relation (DR) approach. The electric and magnetic Generalized Polarizabilities (GPs) of the proton and the structure functions Pll-Ptt/epsilon and Plt are determined at four-momentum transfer squared Q2=0.92 and 1.76 GeV2. The DR analysis is consistent with the low-energy expansion analysis. The world data set indicates that neither the electric nor magnetic GP follows a simple dipole form.

Measurement of the Generalized Polarizabilities of the Proton in Virtual Compton Scattering at Q2

Measurement of the Generalized Polarizabilities of the Proton in Virtual Compton Scattering at Q2 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 1

Get Book Here

Book Description
We report a Virtual Compton Scattering study of the proton at low CM energies. We have determined the structure functions P{sub LL} - P{sub TT}/[epsilon] and P{sub LT}, and the electric and magnetic Generalized Polarizabilities (GPs) [alpha]{sub E}(Q2) and [beta]{sub M}(Q2) at momentum transfer Q2 = 0.92 and 1.76 GeV2. The electric GP shows a strong fall-off with Q2, and its global behavior does not follow a simple dipole form. The magnetic GP shows a rise and then a fall-off; this can be interpreted as the dominance of a long-distance diamagnetic pion cloud at low Q2, compensated at higher Q2 by a paramagnetic contribution from [pi]N intermediate states.

Compton Scattering from the Proton Below Pion Threshold

Compton Scattering from the Proton Below Pion Threshold PDF Author: Bruce Everett MacGibbon
Publisher:
ISBN:
Category :
Languages : en
Pages : 296

Get Book Here

Book Description
The Compton scattering cross section on the proton was measured at laboratory angles of 90$spcirc$ and 135$spcirc$, using 70-100 MeV tagged photons, and simultaneously using 100-150 MeV untagged photons, in order to determine the electric and magnetic polarizabilities. The 135$spcirc$ cross section is sensitive to the difference of the electric and magnetic polarizabilities, $bar alpha - barbeta$, while the 90$spcirc$ cross section is sensitive to the electric polarizability $bar alpha$. Using the model independent sum rule constraint for $bar alpha$ + $bar beta$ and a model dependent dispersion relation calculation, the values for the polarizabilities extracted from the cross sections are:$$bar alpha = (12.5 pm 0.6 pm 0.8 pm 0.6) times 10sp{-4} fmsp3cr bar beta = (1.8 mp 0.6 mp 0.8 mp 0.6) times 10sp{-4} fmsp3$$where the errors shown are statistical, systematic, and model, respectively.