Download or read book Measurement of Target Single spin Asymmetry in Charged Kaon Electroproduction on a Transversely Polarized 3He Target written by Youcai Wang and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The subject of quark transverse spin and transverse momentum distribution are two current research frontier in understanding the spin structure of the nucleons. The goal of the research reported in this dissertation is to extract new information on the quark transversity distribution and the novel transverse-momentum-dependent Sivers function in the neutron. A semi-inclusive deep inelastic scattering experiment was performed at the Hall A of the Jefferson laboratory using 5.9 GeV electron beam and a transversely polarized ^{3}He target. The scattered electrons and the produced hadrons (pions, kaons, and protons) were detected in coincidence with two large magnetic spectrometers. By regularly flipping the spin direction of the transversely polarized target, the single-spin-asymmetry (SSA) of the semi-inclusive deep inelastic reaction ^{3}He^{uparrow}(e,e'h^{pm})X was measured over the kinematic range 0.13
Download or read book Measurement of Single target Spin Asymmetries in the Electroproduction of Negative Pions in the Semi inclusive Deep Inelastic Reaction N1 e E pi X on a Transversely Polarized 3He Target written by and published by . This book was released on 2010 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experiment E06010 measured the target single spin asymmetry (SSA) in the semiinclusive deep inelastic (SIDIS) n1!e, e'[pi]- )X reaction with a transversely polarized 3He target as an e ective neutron target. This is the very rst independent measurement of the neutron SSA, following the measurements at HERMES and COMPASS on the proton and the deuteron. The experiment acquired data in Hall A at Je erson Laboratory with a continuous electron beam of energy 5.9 GeV, probing the valence quark region, with x = 0.13 2!0.41, at Q2 = 1.31 2!3.1 GeV2. The two contributing mechanisms to the measured asymmetry, viz, the Collins effect and the Sivers effect can be realized through the variation of the asymmetry as a function of the Collins and Sivers angles. The neutron Collins and Sivers moments, associated with the azimuthal angular modulations, are extracted from the measured asymmetry for the very first time and are presented in this thesis. The kinematics of this experiment is comparable to the HERMES proton measurement. However, the COMPASS measurements on deuteron and proton are in the low-x region. The results of this experiment are crucial as the first step toward the extraction of quark transversity and Sivers distribution functions in SIDIS. With the existing results on proton and deuteron, these new results on neutron will provide powerful constraints on the transversity and Sivers distributions of both the u and d-quarks in the valence region.
Download or read book Single Spin Asymmetries in Charged Kaon Production from Semi inclusive Deep Inelastic Scattering on a Transversely Polarized math mmultiscripts mi Mathvariant written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the first measurement of target single spin asymmetries of charged kaons produced in semi-inclusive deep inelastic scattering of electrons off a transversely polarized 3He target. Both the Collins and Sivers moments, which are related to the nucleon transversity and Sivers distributions, respectively, are extracted over the kinematic range of 0.1
Download or read book Measurement of Single target Spin Asymmetries in the Electroproduction of Negative Pions in the Semi inclusive Deep Inelastic Reaction N u2191 e e X on a Transversely Polarized 3He Target written by and published by . This book was released on 2010 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experiment E06010 measured the target single spin asymmetry (SSA) in the semiinclusive deep inelastic (SIDIS) n↑(e,e'?-)X reaction with a transversely polarized 3He target as an e ective neutron target. This is the very rst independent measurement of the neutron SSA, following the measurements at HERMES and COMPASS on the proton and the deuteron. The experiment acquired data in Hall A at Je erson Laboratory with a continuous electron beam of energy 5.9 GeV, probing the valence quark region, with x = 0.13 → 0.41, at Q2 = 1.31 → 3.1 GeV2. The two contributing mechanisms to the measured asymmetry, viz, the Collins effect and the Sivers effect can be realized through the variation of the asymmetry as a function of the Collins and Sivers angles. The neutron Collins and Sivers moments, associated with the azimuthal angular modulations, are extracted from the measured asymmetry for the very first time and are presented in this thesis. The kinematics of this experiment is comparable to the HERMES proton measurement. However, the COMPASS measurements on deuteron and proton are in the low-x region. The results of this experiment are crucial as the first step toward the extraction of quark transversity and Sivers distribution functions in SIDIS. With the existing results on proton and deuteron, these new results on neutron will provide powerful constraints on the transversity and Sivers distributions of both the u and d-quarks in the valence region.
Download or read book Measurement of Single target Spin Asymmetries in the Electroproduction of Negative Pions in the Semi inclusive Deep Inelastic Reaction N up Arrow e pi X on a Transversely Polarized 3He Target written by Chiranjib Dutta and published by . This book was released on 2010 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of Single and Double Spin Asymmetries in Deep Inelastic Pion Electroproduction with a Longitudinally Polarized Target written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the first measurement of the transverse momentum dependence of double spin asymmetries in semi-inclusive production of pions in deep inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Thomas Jefferson National Accelerator Facility (JLab). A significant non-zero $\sin2\phi$ single spin asymmetry was also observed for the first time indicating strong spin-orbit correlations for transversely polarized quarks in the longitudinally polarized proton. The azimuthal modulations of single spin asymmetries have been measured over a wide kinematic range.
Download or read book Recent Results of Target Single Spin Asymmetry Experiments at Jefferson Lab written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report recent results from Jefferson Lab Hall A "Neutron Transversity" experiment (E06-010). Transversely polarized target single-spin asymmetry AUT and beam-target double-spin asymmetry A{sub LT} have been measured in semi-inclusive deep-inelastic scattering (SIDIS) reactions on a polarized neutron (3He) target. Collins-type and Sivers-type asymmetries have been extracted from A{sub UT} for charged pion SIDIS productions, which are sensitive to quark transversity and Sivers distributions, correspondingly. Double spin asymmetry A{sub LT} is sensitive to a specific quark transverse momentum dependent parton distribution (TMD), the so-called "transverse helicity" (g{sub 1T}) distributions. In addition, target single-spin asymmetries A{sub y} in inclusive electron scattering on a transversely polarized 3He target in quasi-elastic and deep inelastic kinematics were also measured in Hall A.
Download or read book Single Spin Asymmetries in Charged Pion Production from Semi Inclusive Deep Inelastic Scattering on a Transversely Polarized 3 He Target written by and published by . This book was released on 2011 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the first measurement of target single spin asymmetries in the semi-inclusive $^3{He}(e, e'\pi^\pm)X$ reaction on a transversely polarized target. The experiment, conducted at Jefferson Lab using a 5.9 GeV electron beam, covers a range of 0.14 $
Download or read book Single spin Asymmetry in Electro production of N n Pairs from a Transversely Polarized Proton Target at the HERMES Experiment written by Xiao-Rui Lu and published by . This book was released on 2008 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of Azimuthal Asymmetries with Respect to Both Beam Charge and Transverse Target Polarization in Exclusive Electroproduction of Real Photons written by and published by . This book was released on 2008 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the Single Spin Asymmetry and Polarized Structure Function Sigma Lt in the Exclusive P e pol E K lambda Reaction written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The single spin beam asymmetry, ALTÃ?Â?Ã?Â?Ã?Â?Ã?Â[cent]Ã?Â?Ã?Â?Ã?Â?Ã?Â?Ã?Â?Ã?Â?Ã?Â?Ã?Â2, and the polarized structure function, Ã?Â?Ã?Â?Ã?Â?Ã?Â[8F]Ã?Â?Ã?Â?Ã?Â?Ã?Â?LTÃ?Â?Ã?Â?Ã?Â?Ã?Â[cent]Ã?Â?Ã?Â?Ã?Â?Ã?Â?Ã?Â?Ã?Â?Ã?Â?Ã?Â2, for the reaction in the resonance region have been measured and extracted using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Data were taken at an electron beam energy of 2.57 GeV. The large acceptance of CLAS allows for full azimuthal angle coverage over a large range of kaon center-of-mass angles. Preliminary results are presented that span a range in Q2 from 0.4 to 1.4 (GeV)2 and in W from threshold up to 2.1 GeV. Comparison to existing theoretical calculations are also presented. The fifth structure function is sensitive to the interferences between resonant and non-resonant amplitudes. This measurement is part of a larger CLAS program to measure cross sections and polarization observables for kaon electroproduction in the nucleon resonance region.
Download or read book Measurement of the Single Spin Asymmetry and Polarized Structure Function Sigma Lt in the Exclusive P e pol E K lambda Reaction written by B. A. Raue and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The single spin beam asymmetry, A{sub LT'}, and the polarized structure function, {sigma}{sub LT'}, for the p({rvec e}, e'K{sup +}){Lambda} reaction in the resonance region have been measured and extracted using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Data were taken at an electron beam energy of 2.57 GeV. The large acceptance of CLAS allows for full azimuthal angle coverage over a large range of kaon center-of-mass angles. Preliminary results are presented that span a range in Q{sup 2} from 0.4 to 1.4 (GeV){sup 2} and in W from threshold up to 2.1 GeV. Comparison to existing theoretical calculations are also presented. The fifth structure function is sensitive to the interferences between resonant and non-resonant amplitudes. This measurement is part of a larger CLAS program to measure cross sections and polarization observables for kaon electroproduction in the nucleon resonance region.
Download or read book Precision Measurement of the Spin dependent Asymmetry in the Threshold Region of Quasielastic 3He written by and published by . This book was released on 2002 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first precision measurement of the spin-dependent asymmetry in the threshold region of polarized 3He(polarized e, e') was carried out in Hall A at the Jefferson Laboratory, using a longitudinally polarized continuous electron beam incident on a high-pressure polarized 3He gas target. The polarized electron beam was generated by illuminating a strained GaAs cathode with high intensity circularly polarized laser light, and an average beam polarization of about 70% was achieved. The 3He target was polarized based on the principle of spin-exchange optical pumpint and the average target polarization was about 30%. The scattered electrons were detected in the two Hall A high resolution spectrometers, HRSe and HRSh. The data from HRSh were used for this analysis and covered both the elastic peak and the threshold region. Two kinematic points were measured in the threshold region, one with a central Q2-value of 0.1 (GeV/c)2 at an incident beam energy E0 = 0.778 GeV and the other with a central Q2-value of 0.2 (GeV/c)2 at E-0 = 1.727 GeV. The average beam current was 10 mu-A, which was mainly due to the limitation of the polarized 3He target. The measured asymmetry was compared with both plane wave impulse approximation (PWIA) calculations and non-relativistic full Faddeev calculations which include both final-state interactions (FSIs) and meson-exchange currents (MECs) effects. The poor description of the data by PWIA calculations at both Q2-values suggests the existence of strong FSI and MEC effects in the threshold region of polarized 3He (polarized e, e'). Indeed, the agreement between the data and full calculations is very good at Q2 = 0.1 (GeV/c)2. On the other hand, a small discrepancy at Q2 = 0.2 (GeV/c)2 is observed, which might be due to some Q2 -dependent effects such as relativity and three-nucleon forces (3NFs), which are not included in the framework of non-relativistic Faddeev calculations. Some preliminary results show that 3 NF effects are indeed non-negligible in the threshold region and more theoretical work is currently underway towards a better understanding of both effects. With recent development and success of the chiral perturbation theory, it is hopeful that a future application of the resulting chiral N N forces to electrodisintegration of 3He might solve the present discrepancy.
Download or read book SPIN 2002 written by Yousef I. Makdisi and published by American Institute of Physics. This book was released on 2003-09-04 with total page 1198 pages. Available in PDF, EPUB and Kindle. Book excerpt: The SPIN 2002 Proceedings describe the recent advances in the field of spin physics. The topics cover research in high energy and nuclear physics and the study of the nuclear spin structure. The symposium also covers advances in polarized proton and electron acceleration and storage as well as polarized ion sources and targets. The first measurement of spin physics observables in pp collisions at center of mass energy of 200 Gev was announced at this symposium.
Download or read book Transverse target spin Asymmetry in Exclusive W meson Electroproduction written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Single and Double Polarization Asymmetries from Deeply Virtual Exclusive Pi 0 Electroproduction written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The target and double spin asymmetry measurements of exclusive p0 electroproduction were performed for the first time in DIS region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS) and longitudinally polarized proton target. The wide kinematic coverage and good resolution of CLAS allowed measurements in full azimuthal range providing an opportunity to extract single and double spin asymmetries proportional to polarized structure functions. Their angular dependencies in hadronic center-of-mass system were analyzed, and extracted moments are compared to recent theoretical handbag-based calculations based on chiral-even and chiral-odd GPDs contributions. The interpretation of present results within the framework of the modified perturbative approach and their use as a constraint for models of the t behavior will be discussed.
Download or read book Single Spin Asymmetries at CLAS written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Single spin asymmetries (SSA) are crucial tools in the study of the spin structure of hadrons in pion electroproduction, since they are directly related to some hot topics, including transverse polarization distribution functions, fragmentation of polarized quarks and generalized parton distribution functions. At low beam energies, when the virtual photon has a relatively large angle with respect to the initial spin direction, the measured single-target spin-dependent sin [phi] moment in the cross section for the longitudinally polarized target contain contributions from the target spin components, both longitudinal and transverse with respect to the photon direction. This contribution presents preliminary results from Jefferson Lab's CLAS detector on beam and target SSA in pion azimuthal distributions in one particle inclusive electroproduction in the DIS regime (Q2> 1GeV 2,W> 2GeV) off a polarized NH3 target.
