Abstract/Details

The spin structure of the neutron


1998 1998

Other formats: Order a copy

Abstract (summary)

A description of SLAC experiment E154, a precision measurement of the neutron's longitudinal spin structure function $g\sbsp{1}{n},$ is presented. Deep inelastic electron scattering was used to measure the structure function in the kinematic range $0.014<x<0.7,$ and $1<Q\sp2<17$ GeV$\sp2.$ A measurement of the transverse spin structure function $g\sbsp{2}{n}$ was also made, but with significantly lower statistical precision. Electrons with an average polarization of $82\pm2$% and an energy of 48.3 GeV were scattered off polarized $\sp3$He nuclei having an average polarization of 38%. Two independent magnetic spectrometers set at scattering angles of 2.75$\sp\circ$ and 5.5$\sp\circ$ were used to acquire about 100 million events during a two month run in late 1995. The data were analyzed to yield the integral over the measured region: $\int\sbsp{0.014}{0.7}\ g\sbsp{1}{n}(x)dx=$ ${-}$0.036 $\pm$ 0.004(stat) $\pm$ 0.005(syst), which is several standard deviations below the Ellis-Jaffe sum rule predictions. When these data were combined with the proton $g\sbsp{1}{p}$ structure function data from the SMC and E143 experiments, the Bjorken sum rule over the measured x range was found to be within 10% of the predicted value. The integral of the $g\sbsp{2}{n}$ data, dominated by the statistical uncertainty, was found to be $\int\sbsp{0.014}{0.7}\ g\sbsp{2}{n}(x)dx=$ 0.19 $\pm$ 0.17(stat) $\pm$ 0.02(syst), in agreement with the Burkhardt-Cottingham sum rule prediction. The $g\sbsp{1}{n}$ structure function data at low x were found to be inconsistent with the traditional asymptotic forms, bringing into question the methods used in the past.

Indexing (details)


Subject
Particle physics
Classification
0798: Particle physics
Identifier / keyword
Pure sciences; Bjorken sum rule; deep inelastic scattering
Title
The spin structure of the neutron
Author
Churchwell, Steven T.
Number of pages
174
Publication year
1998
Degree date
1998
School code
0118
Source
DAI-B 59/02, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
ISBN
9780591758498, 0591758490
Advisor
Peterson, Gerald A.
University/institution
University of Massachusetts Amherst
University location
United States -- Massachusetts
Degree
Ph.D.
Source type
Dissertations & Theses
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
9823726
ProQuest document ID
304431068
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
http://search.proquest.com/docview/304431068
Access the complete full text

You can get the full text of this document if it is part of your institution's ProQuest subscription.

Try one of the following:

  • Connect to ProQuest through your library network and search for the document from there.
  • Request the document from your library.
  • Go to the ProQuest login page and enter a ProQuest or My Research username / password.