Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7
Book Description
Single-spin Azimuthal Asymmetry in Exclusive Electroproduction of Π+ [Pi +] Mesons on Transversely Polarized Protons
Single-spin Azimuthal Asymmetry in Exclusive Electroproduction of [pi]+ Mesons on Transversely Polarized Protons
Single-spin Azimuthal Asymmetry in Exclusive Electroproduction of [pi] + Mesons
Single Spin Azimuthal Asymmetry in Exclusive Electroproduction of Π+ [pi] Mesons
Single Spin Azimuthal Asymmetry in Exclusive Electroproduction of _p63_1hn+ [pi] Mesons
Single Spin Azimuthal Asymmetry in Exclusive Electroproduction of P+ [pi] Mesons
Transverse-target Single-spin Azimuthal Asymmetry in Hard Exclusive Electroproduction of Single Pions at HERMES
Measurement of the Single Spin Azimuthal Asymmetry in the Predominantly Exclusive Electroproduction of Photons from the Proton
Author: James H. Ely
Publisher:
ISBN:
Category : Compton effect
Languages : en
Pages : 394
Book Description
Publisher:
ISBN:
Category : Compton effect
Languages : en
Pages : 394
Book Description
Azimuthal Asymmetries in Hard Exclusive Meson Muoproduction Off Transversely Polarized Protons
Author: Johannes ter Wolbeek
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Zusammenfassung: In 2010, the COMPASS experiment at CERN took data with a 160 GeV muon beam and a transversely polarized ammonia target. In this thesis, this data is analyzed for azimuthal target spin asymmetries, including five single spin and three double spin asymmetries in hard exclusive omega meson production.For the asymmetry extraction an extended unbinned maximum likelyhood fit, is used. With this method the eight azimuthal asymmetries from hard exclusive omega meson production plus eight additional asymmetries of the same azimuthal angle modulation from semi-inclusive background events are calculated simultaneously. Therefore every event from the signal region is assigned with the probabilities obtained with the fit to the missing energy distribution.The asymmetries obtained in this analysis can help to constrain Generalized Parton Distributions (GPDs). This is done by comparing the measurements to model calculations of the asymmetries in the COMPASS kinematics. In this thesis the results are compared to the model from Goloskokov and Kroll, which is in good agreement with the data. Especially in combination with results from other vector meson channels, as for example the rho meson, which has already been analyzed, additional constrains on the GPDs E for u and d quarks are enabled
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Zusammenfassung: In 2010, the COMPASS experiment at CERN took data with a 160 GeV muon beam and a transversely polarized ammonia target. In this thesis, this data is analyzed for azimuthal target spin asymmetries, including five single spin and three double spin asymmetries in hard exclusive omega meson production.For the asymmetry extraction an extended unbinned maximum likelyhood fit, is used. With this method the eight azimuthal asymmetries from hard exclusive omega meson production plus eight additional asymmetries of the same azimuthal angle modulation from semi-inclusive background events are calculated simultaneously. Therefore every event from the signal region is assigned with the probabilities obtained with the fit to the missing energy distribution.The asymmetries obtained in this analysis can help to constrain Generalized Parton Distributions (GPDs). This is done by comparing the measurements to model calculations of the asymmetries in the COMPASS kinematics. In this thesis the results are compared to the model from Goloskokov and Kroll, which is in good agreement with the data. Especially in combination with results from other vector meson channels, as for example the rho meson, which has already been analyzed, additional constrains on the GPDs E for u and d quarks are enabled
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
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 284
Book Description
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.
Publisher:
ISBN:
Category :
Languages : en
Pages : 284
Book Description
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.