Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Measurements Of The Proton Electric Form Factor At Jefferson Lab
Download Measurements Of The Proton Electric Form Factor At Jefferson Lab full books in PDF, epub, and Kindle. Read online Measurements Of The Proton Electric Form Factor At Jefferson Lab ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Measurements of the Proton Electric Form Factor at Jefferson Lab by :
Download or read book Measurements of the Proton Electric Form Factor at Jefferson Lab written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The ratio of the electric to magnetic proton form factors, G{sub E{sub p}}/G{sub M{sub p}}, has been obtained in two Hall A experiments, by measuring the polarization of the recoil proton in the elastic scattering of polarized electrons, {rvec e}p --> e{rvec p}, covering the Q2 range of 0.5 to 5.6 GeV2. A linear decrease of the form factor ratio over the whole range is observed in contrast to the previous measurements done with Rosenbluth separation method. The polarization technique discussed here, reduces drastically the systematic uncertainties of the results as compared with the Rosenbluth separation measurements.
Book Synopsis The Proton Form Factor Ratio Measurements at Jefferson Lab by :
Download or read book The Proton Form Factor Ratio Measurements at Jefferson Lab written by and published by . This book was released on 2014 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ratio of the proton form factors, G{sub Ep}/G{sub Mp}, has been measured from Q2 of 0.5 GeV2 to 8.5 GeV2, at the Jefferson Laboratory, using the polarization transfer method. This ratio is extracted directly from the measured ratio of the transverse and longitudinal polarization components of the recoiling proton in elastic electron-proton scattering. The discovery that the proton form factor ratio measured in these experiments decreases approximately linearly with four-momentum transfer, Q2, for values above ~1 GeV2, is one of the most significant results to come out of JLab. These results have had a large impact on progress in hadronic physics; and have required a significant rethinking of nucleon structure. The increasingly common use of the double-polarization technique to measure the nucleon form factors, in the last 15 years, has resulted in a dramatic improvement of the quality of all four nucleon electromagnetic form factors, G{sub Ep}, G{sub Mp}, G{sub En} and G{sub Mn}. There is an approved experiment at JLab, GEP(V), to continue the ratio measurements to 12 GeV2. A dedicated experimental setup, the Super Bigbite Spectrometer (SBS), will be built for this purpose. It will be equipped with a focal plane polarimeter to measure the polarization of the recoil protons. The scattered electrons will be detected in an electromagnetic calorimeter. In this presentation, I will review the status of the proton elastic electromagnetic form factors and discuss a number of theoretical approaches to describe nucleon form factors.
Book Synopsis Proton Form Factor Measurements at Jefferson Lab by : Charles Perdrisat
Download or read book Proton Form Factor Measurements at Jefferson Lab written by Charles Perdrisat and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In two experiments at Jefferson Lab in Hall A, the first one in 1998 and the second in 2000, the ratio of the electromagnetic form factors of the proton was obtained by measuring P{sub t} and P{sub ell}, the transverse and longitudinal recoil proton polarization components, respectively, in {rvec e}p {yields} e{rvec p}; the ratio G{sub E{sub p}}/G{sub M{sub p}} is proportional to P{sub t}/P{sub {ell}}. Simultaneous measurement of P{sub t} and P{sub {ell}} provides good control of the systematic uncertainty. The first measurement of G{sub E{sub p}}/G{sub M{sub p}} ratio was made to Q{sup 2} = 3.5 GeV{sup 2} and the second measurement to Q{sup 2} = 5.6 GeV{sup 2}. The results from these two experiments indicate that the ratio scales like 1/Q{sup 2}, in stark contrast with cross section data analyzed by the Rosenbluth separation method which gives a constant value for this ratio. The incompatibility of the recoil polarization results with most of the Rosenbluth separation results appears now well established above Q{sup 2} of about 3 GeV{sup 2}. The consensus at the present time is that the interference of the two-photon exchange with the Born term, which had been deemed negligible until recently, might explain the discrepancy between the results of the two techniques; the possibility that the discrepancy is due to incomplete radiative correction has also been recently discussed.
Book Synopsis Measurements of the Strangeness Content of the Proton Through Parity Violating Electron Scattering at JLAB. by :
Download or read book Measurements of the Strangeness Content of the Proton Through Parity Violating Electron Scattering at JLAB. written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors have measured the parity violating asymmetry in the cross section for elastic scattering of longitudinally polarized electrons from protons at 3.36 GeV incident energy and 0.48 GeV/c[sup 2] momentum transfer at Jefferson Lab. This asymmetry is[minus]14.5[+-] 2.3 ppm, consistent with the Standard Model with no contribution from strange quarks. They extract the combination of strange form factors G[sub E][sup s]+ 0.39G[sub M][sup s]= 0.023[+-] 0.034(stat)[+-] 0.022(syst)[+-] 0.026[delta]G[sub E][sup n], where the last error arises from the neutron electric form factor.
Book Synopsis Final Analysis of Proton Form Factor Ratio Data at Q2 by :
Download or read book Final Analysis of Proton Form Factor Ratio Data at Q2 written by and published by . This book was released on with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently published measurements of the proton electromagnetic form factor ratio R = [mu]p GEp/GMp at momentum transfers Q2 up to 8.5 GeV2 in Jefferson Lab Hall C deviate from the linear trend of previous measurements in Jefferson Lab Hall A, favoring a slower rate of decrease of R with Q2. While statistically compatible in the region of overlap with Hall A, the Hall C data hint at a systematic difference between the two experiments. This possibility was investigated in a reanalysis of the Hall A data. We find that the original analysis underestimated the background in the selection of elastic events. The application of an additional cut to further suppress the background increases the results for R, improving the consistency between Halls A and C.
Book Synopsis New Results on the Electric Form Factor of the Proton by :
Download or read book New Results on the Electric Form Factor of the Proton written by and published by . This book was released on 2002 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The longitudinal, P, and transverse, Pt, polarizations of the recoil proton were measured for the elastic p reaction in Hall A at JLab. The ratio of the electric, GEp, to the magnetic, GMp, form factors of the proton was obtained from the ratio Pt/P. Using this technique, an earlier experiment [1] in Hall A at JLab measured GEp/GMp for the four-momentum transferred, Q2, from 0.5 to 3.5 GeV2 and found that above Q2 0.8 GeV2 the ratio falls off linearly with Q2. New data presented here extend the measurement of GEp/GMp to Q2 = 5.6 GeV2 and shows that it continues to fall linearly with Q2.
Book Synopsis Measurements of the Electromagnetic Form Factor of the Proton at Jlab by :
Download or read book Measurements of the Electromagnetic Form Factor of the Proton at Jlab written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The ratio of the proton's elastic electromagnetic form factors G{sub E{sub p}}/G{sub M{sub p}} was obtained by measuring P{sub t} and P{sub {ell}}, the transverse and longitudinal recoil proton polarization, respectively. For the elastic reaction {rvec e}p --> e{rvec p}, G{sub E{sub p}}/G{sub M{sub p}} is proportional to P{sub t}/P{sub {ell}}. The simultaneous measurement of P{sub t} and P{sub {ell}} in a polarimeter reduces systematic uncertainties. The results for the ratio G{sub E{sub p}}/G{sub M{sub p}} measured in Hall A so far show a systematic decrease with increasing Q2, indicating for the first time a definite difference in the distribution of charge and magnetization in the proton. Together these experiments cover the Q2- range of 0.5 to 5.6 GeV2. A new experiment is currently being prepared, to extend the Q2-range to 9 GeV2 in Hall C.
Book Synopsis High-precision Measurement of the Proton Elastic Form Factor Ratio [mml by :
Download or read book High-precision Measurement of the Proton Elastic Form Factor Ratio [mml written by and published by . This book was released on 2011 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, we report a new high precision measurement of the proton elastic form factor ratio [mu]pGE/GM for the four-momentum transfer squared Q2 = 0.3-0.7 (GeV/c)2. The measurement was performed at Jefferson Lab (JLab) in Hall A using recoil polarimetry. With the achieved ~1% total uncertainty, the new data clearly show that the deviation of the ratio [mu]pGE/GM from unity observed in previous polarization measurements at high Q2 continues down to the lowest Q2 value of this measurement. The updated global fit that includes the new results yields in this Q2 range an electric (magnetic) form factor ~2% smaller (~1% larger) than the previous global fit. We obtain new extractions of the proton electric and magnetic radii, which are (rE2)1/2 = 0.875 ± 0.010 fm and (rM2)1/2 = 0.867 ± 0.020 fm. Moreover, the charge radius is consistent with other recent extractions based on the electron-proton interaction, including the atomic hydrogen Lamb shift measruements, which suggests a missing correction in the comparison of measurements of the proton charge radius using electron probes and the recent extraction from the muonic hydrogen Lamb shift.
Book Synopsis Proton Elastic Form Factor Ratio by : Charles Perdrisat
Download or read book Proton Elastic Form Factor Ratio written by Charles Perdrisat and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The ratio of the electric and magnetic proton form factors, G{sub Ep}/G{sub Mp}, has been obtained in two Hall A experiments, from measurements of the longitudinal and transverse polarization of the recoil proton, P{sub l} and P{sub t}, respectively, in the elastic scattering of polarized electrons, {rvec e}p {yields} e{rvec p}. Together these experiments cover the Q{sup 2}-range 0.5 to 5.6 GeV{sup 2}. A new experiment is currently being prepared, to extend the Q{sup 2}-range to 9 GeV{sup 2} in Hall C.
Book Synopsis Proceedings of the 16th and 17th Annual Hampton University Graduate Studies (HUGS) Summer Schools on Quarks, Hadrons, and Nuclei by : Jos L. Goity
Download or read book Proceedings of the 16th and 17th Annual Hampton University Graduate Studies (HUGS) Summer Schools on Quarks, Hadrons, and Nuclei written by Jos L. Goity and published by World Scientific. This book was released on 2004 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains lectures presented at the Sixteenth and Seventeenth Annual Hampton University Graduate Studies at the Continuous Electron Beam Accelerator Facility (HUGS at CEBAF) Summer Schools. The HUGS summer school brings pedagogical lectures to graduate students who are working on doctoral theses in nuclear physics. It has a balance of theory and experiment, and lecturers address topics of high current interest in strong interaction physics, particularly in electron scattering. Many HUGS lecturers lead major experimental efforts, and are internationally renowned for their contributions to the field. The proceedings have been selected for coverage in: . OCo Index to Scientific & Technical Proceedings (ISTP CDROM version / ISI Proceedings). OCo CC Proceedings OCo Engineering & Physical Sciences."
Book Synopsis Physics Division Annual Report by : Argonne National Laboratory. Physics Division
Download or read book Physics Division Annual Report written by Argonne National Laboratory. Physics Division and published by . This book was released on 2001 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Jefferson Lab Experiments Shed New Light on the Proton by :
Download or read book Jefferson Lab Experiments Shed New Light on the Proton written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In experiments 93-027 and 99-007 at Jefferson Lab (JLab) the ratio of the electromagnetic elastic form factors of the proton, G{sub E{sub p}}/G{sub M{sub p}}, was measured with high precision, up to four momentum transfer Q2 of 3.5 GeV2 and 5.6 GeV2, respectively, with the recoil polarization technique. The data from these two JLab experiments have shown an unexpected and significantly different Q2-dependence for the electric and magnetic form factors, starting at about Q2=1 GeV2, up to the maximum value of 5.6 GeV2, revealing a definite difference in spatial distribution of charge and magnetization at short distances. The combined results of the two JLab experiments were surprising as they appeared to contradict the consensus based on Rosenbluth separation results for (G{sub E{sub p}})2 and G{sub M{sub p}}2: the ratio [mu]{sub p}G{sub E{sub p}}/G{sub M{sub p}} obtained with the Rosenbluth method appear to be near 1 up to about 6 GeV2. This un-bridgeable difference between cross section and polarization experiments has been reinforced with two recent JLab Rosenbluth experiments; it appears increasingly difficult to explain it away by methodological or systematic errors. We are currently preparing a third experiment at JLab, this time in Hall C, to extend the Q2-range to 9 GeV2.
Book Synopsis Measurement of the Deuteron Electric and Magnetic Form Factors at Jefferson Lab by :
Download or read book Measurement of the Deuteron Electric and Magnetic Form Factors at Jefferson Lab written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The results from an experiment to measure the electric, A(Q[sup 2]), and magnetic, B(Q[sup 2]), form factors of the deuteron at large momentum transfers at the Jefferson Laboratory (JLAB) will be reported. The experiment performed elastic electron scattering from deuterium in coincidence; it has improved the quality of the existing data in the range of overlap and has significantly extended the Q[sup 2] range of the previous A(Q[sup 2]) SLAC data. The range in the squared four-momentum transfer, Q[sup 2], is 0.7 to 6.0 (GeV/c)[sup 2] for the A(Q[sup 2]) measurements and 0.7 to 1.4 (GeV/c)[sup 2] for the B(Q[sup 2]) measurements. The measurements used the Continuous Electron Beam Accelerator and Hall-A Facilities of JLAB. Incident electron beams of energy 0.5 to 4.4 GeV and current 10 to 120[mu]A were scattered off a high power (500W) cryogenic deuterium/hydrogen target. Scattered electrons and recoiling deuterons were detected in coincidence using the two 4 GeV/c High Resolution Spectrometers (HRS) in Hall-A. Both HRS's used two planes of scintillators for triggering and timing and a drift chamber system for particle tracking. The electron HRS was also equipped with a gas Cherenkov counter and a lead-glass calorimeter for electron identification. Elastic electron-proton scattering in coincidence was used to calibrate the entire double-arm system. The results will be compared to conventional meson-nucleon physics calculations based on the impulse approximation with the inclusion of meson-exchange-currents, and to predictions of dimensional scaling quark models and perturbative quantum chromodynamics. They are expected to provide a crucial test of nuclear chromodynamics ideas and insights into the transition from the meson-nucleon to quark-gluon descriptions of the two-body nuclear structure.
Book Synopsis Testing QCD Through Spin Observables in Nuclear Targets by : Don G. Crabb
Download or read book Testing QCD Through Spin Observables in Nuclear Targets written by Don G. Crabb and published by World Scientific. This book was released on 2003 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the invited talks and contributed papers presented at the workshop on ?Testing QCD Through Spin Observables in Nuclear Targets?, held at the University of Virginia in April 2002.The workshop was proposed in the context of the large number of experiments that have used polarized deuterons or polarized 3He to extract information about the spin parameters of the neutron. The motivation for this workshop was to study the effects of the nuclear medium on the spin properties of the bound nucleon and to explore issues in QCD that might be resolved through spin observables in nuclear targets: What is the effect of the nuclear medium on the measured asymmetries? How have the latest results on the spin structure of the nucleon and the nucleon form factors changed our thinking? What advances are anticipated in the development of polarized targets?
Book Synopsis International Workshop on Positrons at Jefferson Lab by : Latifa Elouadrhiri
Download or read book International Workshop on Positrons at Jefferson Lab written by Latifa Elouadrhiri and published by American Institute of Physics. This book was released on 2009-08-20 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Newport News, Virginia, 25-27 March 2009
Book Synopsis High Precision Measurement of the Proton Elastic Form Factor Ratio at Low Q2 by :
Download or read book High Precision Measurement of the Proton Elastic Form Factor Ratio at Low Q2 written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiment E08-007 measured the proton elastic form factor ratio?pGE/GM in the range of Q2 = 0.3?0.7(GeV/c)2 by recoil polarimetry. Data were taken in 2008 at the Thomas Jefferson National Accelerator Facility in Virginia, USA. A 1.2 GeV polarized electron beam was scattered off a cryogenic hydrogen target. The recoil proton was detected in the left HRS in coincidence with the elasticly scattered electrons tagged by the BigBite spectrometer. The proton polarization was measured by the focal plane polarimeter (FPP). In this low Q2 region, previous measurement from Jefferson Lab Hall A (LEDEX) along with various fits and calculations indicate substantial deviations of the ratio from unity. For this new measurement, the proposed statistical uncertainty (
Book Synopsis Measurements of the Electric Form Factor of the Neutron at Q2 by : Shigeyuki Tajima
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:
