The proton's spin: A quark model perspective Page: 2 of 14
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
THE PROTON'S SPIN: A QUARK MODEL PERSPECTIVE
F. E. Close
Oak Ridge National Laboratory*, Oak Ridge, TN 37831-6373
University of Tenaessee, Knoxville, TN 37996-1200
Magnetic moments and gA V provide information on the correla-
tions among quark spins and flavors in the proton. I compare this
information with the deep inelastic polarized data from EMC which has
been claimed to show that very little of the proton's spin is due to
the quarks. The possibility that there is significant polarization of
strange quarks within protons is discussed.
Inelastic lepton scattering from nucleons at high momentum transfer meas-
ures the number densities of charged constituents, q(x), q(x), as a function of
the Bjorken variable x (essentially the ratio of the constituent and target
longitudinal momenta in an infinite momentum frame). There is a weak dependence
of these distributions on the momentum transfer, Q2, but I shall suppress this
in much of what follows.
If the beam and target are polarized, one can extract the helicity-
dependent distributions for quarks or antiquarks polarized parallel (q*(x)) or
antiparallel (q+(x)) to the target polarization. I shall define Aq(x) Eq (x) -
q+(x); q(x) E qt(x) + qg(x), and similarly for antiquarks, q.
Data are presented in two ways.1-3) One is in terms of the polarization
A(x) - e 2 (Aq (x) + Al (x))/ e12 (qi(x) + 9 (x)), (1)
*Operated by Martin Marietta Energy Systems, Inc. under Contract
DE-AC05-840R21400 with the U.S.D.O.E.
Here’s what’s next.
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Close, F. E. The proton's spin: A quark model perspective, article, January 1, 1989; Tennessee. (https://digital.library.unt.edu/ark:/67531/metadc1059459/m1/2/: accessed March 20, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.