Measurement of longitudinal double spin asymmetries of [pi]+/- production in p[over-arrow] + p[over-arrow] collisions at [sqrt]s = 200 GeV at RHIC

Spin dependent measurements provide incisive tests for modern theories of particle physics. The discovery that the integral of the quark helicity distribution is much too small to account for the spin of the proton is an excellent case in point. It inspired an intense period of theoretical scrutiny and a new generation of experiments to study [Delta]g, the helicity distribution of gluons in the nucleon. In particular, the unique polarized proton collider at RHIC enables a class of asymmetry measurements that are directly sensitive to gluon polarization. The STAR experiment at RHIC measures the double spin asymmetry A[subscript LL] for a variety of final states in collisions of longitudinally polarized protons in order to constrain [Delta]g. Asymmetries for mid-rapidity charged pion production benefit from large cross sections and the excellent tracking and particle identification capabilities of the STAR Time Projection Chamber. This thesis presents the first measurements of charged pion A[subscript LL] at STAR. The measurements are compared to predictions based on perturbative QCD calculations and from this comparison model-dependent constraints are placed on the integral gluon polarization [Delta]G.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2010

Author dc:creator

• Kocoloski, Adam (Adam Philip)

Advisor dc:contributor.advisor

• Bernd Surrow.

• Physics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/62647

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/62647