Download or read book Measurement of the Electric Form Factor of the Neutron at High Momentum Transfer written by Jonathan Miller and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the Electric Form Factor of the Neutron at High Momentum Transfer written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The E02-013 collaboration s precision measurement of the electric form factor of the neutron at high momentum took place in Hall A of Jefferson Laboratory [1]. Four kinematic points spread in Q2 from 1.2 to 3.5 (GeV/c)2 reach the region of momentum transfer where there is little ambiguity that the form factors are dominated by the valence quarks. The electric form factor provides important constraints on the generalized parton distributions (GPDs) of the nucleon and therefore to understand the currently unknown quark angular orbital moments. The talk presented newly obtained results for GnE including at Q2 of 2.5 (GeV/c)2. These measurements provide access to twice the range of momentum transfer for complete iso-spin decomposition of the nucleon form factors. The form factors of the u and d quarks were also presented. The measurement used a double polarization asymmetry method [2][3] with He polarized up to 55% (provided by a novel hybrid alkali optical pumping scheme utilizi.
Download or read book A Measurement of the Neutron Electric Form Factor at Very Large Momentum Transfer Using Polaried Electrions Scattering from a Polarized Helium 3 Target written by and published by . This book was released on 2010 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: Knowledge of the electric and magnetic elastic form factors of the nucleon is essential for an understanding of nucleon structure. Of the form factors, the electric form factor of the neutron has been measured over the smallest range in Q2 and with the lowest precision. Jefferson Lab experiment 02-013 used a novel new polarized 3 He target to nearly double the range of momentum transfer in which the neutron form factor has been studied and to measure it with much higher precision. Polarized electrons were scattered off this target, and both the scattered electron and neutron were detected. Gn E was measured to be 0.0242 ± 0.0020(stat) ± 0.0061(sys) and 0.0247 ± 0.0029(stat) ± 0.0031(sys) at Q2 = 1.7 and 2.5 GeV2 , respectively.
Download or read book A Measure of the Neutron Electric Form Factor at Very Large Momentum Transfer Using Polarized Electrons Scattering from a Polarized Helium 3 Target written by Aidan Michael Kelleher and published by . This book was released on 2010 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Precision Measurements of the Neutron Electric Form Factor at High Momentum Transfers written by Ameya Suresh Kolarkar and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurements of the Electric Form Factor of the Neutron at Q2 written by and published by . This book was released on 2003 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: Precise measurements of the electric form factor of the neutron, Gn E, over a wide range of the square of the four-momentum transfer, Q2, are important for understanding nucleon and nuclear electromagnetic structure. In the non-relativistic limit, the electric and magnetic form factors are related to the charge and magnetization distribution inside a nucleon, respectively. The measured values of the form factors also serve as an important test for nucleon models. Among the four nucleon form factors, the electric form factor of the neutron, Gn E, is the most difficult one to measure and therefore has been very poorly known especially in the region Q2 > 1 (GeV/c)2 due to the lack of a free neutron target and the small value of Gn E. The Jefferson Laboratory E93-038 collaboration measured the ratio of the electric to magnetic form factor of the neutron, g = Gn E/Gn M, at three acceptance-averaged Q2 values of 0.45, 1.13 and 1.45 (GeV/c)2 using the quasi-elastic 2H(ẽ, e0ñ)1H reaction. In our experiment, an electron was scattered quasielastically from a neutron in a liquid-deuterium target, and the electron was detected in an electron spectrometer in coincidence with the neutron which was detected in a neutron polarimeter. The polarimeter was used to analyze the polarization of the recoil neutrons by measuring the np elastic scattering asymmetry. The experiment was performed in Hall-C at Thomas Jefferson National Accelerator Facility during the period from September 2000 to April 2001. The value of g was determined from the measured ratio of the sideways and longitudinal components of the neutron polarization vector. The values for Gn E were computed from our measured values of g = Gn E/Gn M using the Gn M values obtained from a fit to the world data. The E93-038 collaboration reported the first measurements of Gn E using polarization techniques at Q2 greater than 1 (GeV/c)2. Furthermore, our measurements of Gn E at the two higher Q2 values of 1.13 and 1.45 (GeV/c)2 are more precise than prior measurements at lower Q2. In this dissertation, the data analyses and our results for g and Gn E at Q2=0.45 (GeV/c)2 and Q2=1.13 (GeV/c)2 are given. Our high-accuracy data are included with the 'world' data for Gn E to form an improved data set that was fit with an empirical function to give a simple parameterization of Gn E as a function of Q2. In addition, the data for the ratio Gn E/Gn M are compared to theoretical models of the nucleon. We found that no theoretical model predicts both proton and neutron form factor data.
Download or read book Measurements of the Electric Form Factor of the Neutron at Q2 written by Shigeyuki Tajima and published by . This book was released on 2003 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Neutron Electric Form Factor to Q2 written by and published by . This book was released on 2004 with total page 541 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nucleon elastic electromagnetic form factors are fundamental quantities needed for an understanding of nucleon and nuclear electromagnetic structure. The evolution of the Sachs electric and magnetic form factors with Q2, the square of the four-momentum transfer, is related to the distribution of charge and magnetization within the nucleon. High precision measurements of the nucleon form factors are essential for stringent tests of our current theoretical understanding of confinement within the nucleon. Measurements of the neutron form factors, in particular, those of the neutron electric form factor, have been notoriously difficult due to the lack of a free neutron target and the vanishing integral charge of the neutron. Indeed, a precise measurement of the neutron electric form factor has eluded experimentalists for decades; however, with the advent of high duty-factor polarized electron beam facilities, experiments employing polarization degrees of freedom have finally yielded the first precise measurements of this fundamental quantity. Following a general overview of the experimental and theoretical status of the nucleon form factors, a detailed description of an experiment designed to extract the neutron electric form factor from measurements of the neutron's recoil polarization in quasielastic 2H(e, e')1H scattering is presented. The experiment described here employed the Thomas Jefferson National Accelerator Facility's longitudinally polarized electron beam, a magnetic spectrometer for detection of the scattered electron, and a neutron polarimeter designed specifically for this experiment. Measurements were conducted at three Q2 values of 0.45, 1.13, and 1.45 (GeV/c)2, and the final results extracted from an analysis of the data acquired in this experiment are reported and compared with recent theoretical predictions for the nucleon form factors.
Download or read book Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio at High Momentum Transfer written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electromagnetic form factors are fundamental properties of the nucleon that describe the effect of its internal quark structure on the cross section and spin observables in elastic lepton-nucleon scattering. Double-polarization experiments have become the preferred technique to measure the proton and neutron electric form factors at high momentum transfers. The recently completed GEp-III experiment at the Thomas Jefferson National Accelerator Facility used the recoil polarization method to extend the knowledge of the proton electromagnetic form factor ratio GpE/GpM to Q2 = 8.5 GeV2. In this paper we present the preliminary results of the experiment.
Download or read book Elastic Electron Scattering Measurements of the Neutron Charge Form Factor at Very Low Momentum Transfers written by Jake W Stewart (Jr) and published by . This book was released on 1970 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of the ratio of the neutron-proton electric form factors, G(E sub n)/G(E sub p), were made from elastic electron-deuteron scattering to a precision of approximately 1 to 2% for the range of momentum transfers, q squared of 0.10
Download or read book Measurements of the Electric Form Factor of the Neutron Up to Q2 written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The electric form factor of the neutron was determined from studies of the reaction \rea{} in quasi-elastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the $Q^2$-range over which it is known, we find \GEn{}$ = 0.0225 \pm 0.0017 (stat) \pm 0.0024 (syst)$, $0.0200 \pm 0.0023 \pm 0.0018$, and $0.0142 \pm 0.0019 \pm 0.0013$ for $Q^2$ = 1.72, 2.48, and 3.41~\gevsq, respectively.
Download or read book Measurement of the Neutron Electric Form Factor GEn in Quasielastic Scattering written by and published by . This book was released on 2003 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have measured the electric form factor of the neutron, GEn, at two momentum transfers (Q2= 0.5 and Q2= 1.0 GeV/c2) through quasielastic scattering in Jefferson Lab's Hall C. Longitudinally polarized electrons scattered from polarized deuterated ammonia and GEn was extracted from the beam-target asymmetry AVed which, in quasielastic kinematics, is particularly sensitive to GEn and insensitive to MEC and FSI.
Download or read book Measurement of the Electric Form Factor of the Neutron at Low Momentum Transfers Using a Vector Polarized Deuterium Gas Target at BLAST written by Vitaliy Ziskin and published by . This book was released on 2005 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) A fit to the world's data including new BLAST data determines ... to ... over 0
Download or read book Measurement of the Electric Form Factor of the Neutron at Q2 written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The electric form factor of the neutron was determined from measurements of the d ((almost equal to)e, e n) p reaction for quasielastic kinematics. Polarized electrons were scattered o a polarized deuterated ammonia (15ND3) target in which the deuteron polarization was perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons in a large solid angle detector. We find Gn E = 0.0526 ± 0.0033(stat) ± 0.0026(sys) and 0.0454 ± 0.0054 ± 0.0037 at Q2 = 0.5 and 1.0 (GeV/c)2, respectively.
Download or read book The Electric Form Factor of the Neutron at Low Momentum Transfers as Measured at Bates Large Acceptance Spectrometer Toroid written by Eugene J. Geis and published by . This book was released on 2007 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elastic form factors are characteristic signatures of the electromagnetic properties of hadronic matter. The more precisely we can measure these values, the more powerful becomes the predictability of our theory.
Download or read book Exclusive Reactions At High Momentum Transfer Proceedings Of The International Workshop written by Anatoly Radyushkin and published by World Scientific. This book was released on 2008-03-13 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exclusive reactions are becoming one of the major sources of information about the deep structure of nucleons and other hadrons. The 2007 International Workshop held at Jefferson Lab in Newport News, Virginia, USA — the world's leading facility performing research on nuclear, hadronic and quark-gluon structure of matter — focused on the application of a variety of exclusive reactions at high momentum transfer, utilizing unpolarized and polarized beams and targets, to obtain information about nucleon ground-state and excited-state structure at short distances. This is a subject which is central to the programs of current accelerators and especially planned future facilities.This proceedings volume contains, in concentrated form, information about the newest developments, both theoretical and experimental, in the study of hard exclusive reactions.
