Measurement of the Strange Quark Contribution to Nucleon Structure Through Parity-violating Electron Scattering
Author: Colleen L. Ellis
Publisher:
Published: 2010
Total Pages:
ISBN-13:
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Measurement of the Strange Quark Contribution to Nucleon Structure Through Parity-Violating Electron Scattering
Author:
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Published: 2010
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DOWNLOAD EBOOKThe G0 backward angle experiment, completed in Hall C of the Thomas Jefferson National Accelerator Facility (TJNAF), measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at Q2 = 0.22 and 0.63 (GeV/c)2. The asymmetries are sensitive to strange quark contributions to currents in the nucleon and the nucleon axial-vector current. The results indicate strange quark contributions of lte 10% of the charge and magnetic nucleon form factors at these four-momentum transfers. This was also the first measurement of the anapole moment effects in the axial-vector current at these four-momentum transfers.
Measurement of the Strange Quark Contribution to Proton Structure Through Parity Violating Electron-Proton Scattering
Author: Kazutaka Nakahara
Publisher:
Published: 2006
Total Pages:
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DOWNLOAD EBOOKThe G0 (G-Zero) forward angle experiment completed in Hall C of the Thomas Jefferson National Accelerator Facility (TJNAF) has measured the parity violating asymmetries in elastic electron-proton scattering over a Q2 range of 0.12
Measurement of the Strange Quark Contribution to the Vector Structure of the Proton
Author:
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Published: 2007
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ISBN-13:
DOWNLOAD EBOOKThe goal of the G0 experiment is to determine the contribution of the strange quarks in the quark-antiquark sea to the structure of the nucleon. To this end, the experiment measured parityviolating asymmetries from elastic electron-proton scattering from 0.12 ≤ Q2 ≤ 1.0 (GeV/c)2 at Thomas Jefferson National Accelerator Facility. These asymmetries come from the interference of the electromagnetic and neutral weak interactions, and are sensitive to the strange quark contributions in the proton. The results from the forward-angle measurement, the linear combination of the strange electric and magnetic form factors GsE +[eta]GsM, suggest possible non-zero, Q2 dependent, strange quark contributions and provide new information to understand the magnitude of the contributions. This dissertation presents the analysis and results of the forward-angle measurement. In addition, the G0 experiment measured the beam-normal single-spin asymmetry in the elastic scattering of transversely polarized 3 GeV electrons from unpolarized protons at Q2 = 0.15, 0.25 (GeV/c)2 as part of the forward-angle measurement. The transverse asymmetry provides a direct probe of the imaginary component of the two-photon exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments. The results of the measurement indicate that calculations using solely the elastic nucleon intermediate state are insufficient and generally agree with calculations that include significant inelastic hadronic intermediate state contributions. This dissertation presents the analysis and results of this measurement.
Strange Quark Contributions to Nucleon Electric and Magnetic Form Factors from Parity-violating Electron Scattering Asymmetries in the Backward Angle G0 Experiment
Author: Mathew O. Muether
Publisher:
Published: 2010
Total Pages:
ISBN-13:
DOWNLOAD EBOOKThe G0 collaboration has measured parity-violating asymmetries in elastic electron-proton and quasi-elastic electron-deuteron scattering at Q^2 = 0.22, 0.63 GeV^2. These asymmetries are sensitive to strange quark contributions to electric and magnetic properties of the nucleon, as well as to the axial current of the nucleon. The measurements were made using the polarized beam at Jefferson Laboratory by detecting electrons scattered at ~110 degrees from liquid targets. Together with previous results from the G0 forward angle measurement, the form factors which characterize the strange electric, strange magnetic and axial contributions were found to be G^{s}_{E}(0.221 GeV^2)= -0.0142305 +/- 0.035562 +/- 0.0181952 +/-0.0176497 G^{s}_{M}(0.221 GeV^2)=0.0833777 +/- 0.18337 +/- 0.0854892 +/- 0.0780912 G^{e}_{A}(0.221 GeV^2)=-0.501236 +/- 0.317127 +/- 0.193005 +/- 0.0878386 G^{s}_{E}(0.628 GeV^2)=0.110227 +/-0.0488068 +/- 0.0296044 +/- 0.0236998 G^{s}_{M}(0.628 GeV^2)=-0.12354 +/- 0.10953 +/- 0.0614285 +/- 0.0316972 G^{e}_{A}(0.628 GeV^2)=-0.197329 +/- 0.425414 +/- 0.256755 +/- 0.0948741 with statistical, point-to-point systematic and global systematic uncertainties given respectively. These results indicate small (
A Measurement of the Strange Quark Contributions to the Electromagnetic Form Factors of the Nucleon
Author:
Publisher:
Published: 2006
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ISBN-13:
DOWNLOAD EBOOKG0 is a parity violating electron scattering program at the Thomas Jefferson National Accelerator Facility, and its forward angle measurement is reported in this thesis. In this experiment, parity violating asymmetries of elastic electron-proton scattering were measured over a range of four-momentum transfer from 0.12 to 1.0 (GeV/c)2. From the asymmetries, linear combinations of the strange electric and magnetic form factors of the nucleon, G$s\atop{E}$ + [eta]G$s\atop{M}$, are extracted over the same kinematic range. These results, combined with existing data from other experiments, indicate that both G$s\atop{E}$ and [eta]G$s\atop{M}$ are non-zero and dependent on the four-momentum transfer, with imply non-trivial strange quark contributions to the low energy electromagnetic properties of the nucleon.
Strange Quark Contributions to Parity-Violating Asymmetries in the Backward Angle G0 Electron Scattering Experiment
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Published: 2010
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DOWNLOAD EBOOKFrom Parity Violation to Hadronic Structure and more
Author: Serge Kox
Publisher: Springer Science & Business Media
Published: 2007-06-07
Total Pages: 198
ISBN-13: 3540263454
DOWNLOAD EBOOKAlmost 50 years after the proposal of Lee and Young in 1956 to test the hypothesis of parity violation in weak interactions and the subsequent experimental verification of parity violation by C. S. Wu, parity violation has today become a useful property of weak interactions. This is due to the fact that the focus nowadays has changed: parity violation in weak interactions is no more a topic of investigation but is used as a tool in many different fields ranging from nuclear physics to the search for the hidden extra dimensions requested by string theory. For our first workshop which took place June 5-8, 2002, at the Institut fiir Ke- physik of the Johannes Gutenberg-Universitat Mainz, we concentrated on the in vestigation of the strangeness contribution in the nucleon. This book contains the refereed and selected papers of the second workshop "From Parity Violation to Hadron Structure and more (Part II)", which took place June 8-11, in the Labo- toire de Physique Subatomique et de Cosmologie, in Grenoble. These papers appear in EPJAdirect, the electronic-only part of EPJA, and they are accessible without restrictions. They will also appear in printed form and can be ordered through Springer. The excellent presentations show the dramatic and steady progress in the accuracy of measured parity violating asymmetries over the last few years.
From Parity Violation to Hadronic Structure and more
Author: K. de Jager
Publisher: Springer Science & Business Media
Published: 2008-06-21
Total Pages: 256
ISBN-13: 3540744134
DOWNLOAD EBOOKThis book contains the proceedings of the third international workshop on From Parity Violation to Hadronic Structure and More. The many applications of parity violation are way beyond the scope of what Lee and Yang could have imagined fifty years after their proposal. For the physics topics discussed during this workshop, the application of parity violation has become a standard work horse allowing for the extraction of many physics topics in different experiments.
Parity Violation In Electron Scattering - Proceedings Of The Workshop
Author: E J Beise
Publisher: World Scientific
Published: 1990-08-23
Total Pages: 246
ISBN-13: 9814611506
DOWNLOAD EBOOKThese proceedings cover the recent progress and future directions of parity violation in electron scattering. Both experimental and theoretical issues are discussed, such as those of hadronic structure, radiative corrections, and tests of the standard model. There are three sessions, the first of which serves as a general overview of theory and experiment. The second session deals with the technical aspects of making a measurement of the parity violating asymmetry in electron scattering, including not only detector design but polarized electron beams and beam polarimeters.. The remaining session covers the corrections to lowest order parity violating cross sections.
