Author: Lawrence Henry O'Neill
Publisher:
ISBN:
Category : Collisions (Nuclear physics)
Languages : en
Pages : 540
Book Description
Inclusive Observation of Neutral Pions from Pion-proton Collisions at 14 GeV/c
Nuclear Science Abstracts
Author:
Publisher:
ISBN:
Category : Nuclear energy
Languages : en
Pages : 934
Book Description
Publisher:
ISBN:
Category : Nuclear energy
Languages : en
Pages : 934
Book Description
High Multiplicity Pion Production in 25 GeV/c Pi-minus-proton Collisions
Author: Jerome William Elbert
Publisher:
ISBN:
Category :
Languages : en
Pages : 638
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 638
Book Description
Neutral Pion Double Helicity Asymmetry in Polarized Proton-Proton Collisions at [the Square Root of Sigma]
Author: William Axel Leight
Publisher:
ISBN:
Category :
Languages : en
Pages : 112
Book Description
One of the primary goals of the spin physics program at the STAR experiment is to constrain the polarized gluon distribution function, [delta]g(X,Q2), by measuring the double longitudinal spin asymmetry, ALL, of various final-state channels. Neutral pions provide a potentially powerful final state because they are copiously produced in p+p collisions and have few backgrounds. In 2009, STAR took 14 pb-1 of integrated luminosity of 200 GeV p+p collisions, with average beam longitudinal polarization of 59%. Neutral pions produced in these collisions can be identified using STAR's large-acceptance electromagnetic calorimeter, with help from tracking from the STAR Time Projection Chamber. This work presents a measurement of the inclusive neutral pion ALL from this data, based on a new [pi]0 reconstruction algorithm. A comparison to theoretical predictions and other experimental results suggests that the current best-fit value of AG, the gluon contribution to the proton spin, is too small and that [delta]G is actually comparable in magnitude to the quark contribution to the proton spin [delta][sigma].
Publisher:
ISBN:
Category :
Languages : en
Pages : 112
Book Description
One of the primary goals of the spin physics program at the STAR experiment is to constrain the polarized gluon distribution function, [delta]g(X,Q2), by measuring the double longitudinal spin asymmetry, ALL, of various final-state channels. Neutral pions provide a potentially powerful final state because they are copiously produced in p+p collisions and have few backgrounds. In 2009, STAR took 14 pb-1 of integrated luminosity of 200 GeV p+p collisions, with average beam longitudinal polarization of 59%. Neutral pions produced in these collisions can be identified using STAR's large-acceptance electromagnetic calorimeter, with help from tracking from the STAR Time Projection Chamber. This work presents a measurement of the inclusive neutral pion ALL from this data, based on a new [pi]0 reconstruction algorithm. A comparison to theoretical predictions and other experimental results suggests that the current best-fit value of AG, the gluon contribution to the proton spin, is too small and that [delta]G is actually comparable in magnitude to the quark contribution to the proton spin [delta][sigma].
Measurement of Inclusive Forward Neutral Pion Production in 200 GeV Polarized Proton-proton Collisions at RHIC
Author: Yiqun Wang
Publisher:
ISBN:
Category : Detectors
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category : Detectors
Languages : en
Pages :
Book Description
A Guide to Data in Elementary Particle Physics
Author: G. P. Yost
Publisher:
ISBN:
Category : Information storage and retrieval systems
Languages : en
Pages : 604
Book Description
Publisher:
ISBN:
Category : Information storage and retrieval systems
Languages : en
Pages : 604
Book Description
Energy Research Abstracts
Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 640
Book Description
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 640
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1330
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1330
Book Description
Measurement of Inclusive Production of Neutral Pions at High Transverse Momentum. [100 to 300 GeV/c, Scaling]
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
These are the results of a measurement of inclusive production at high transverse momentum (P perpendicular to) of neutral pions (.pi./sup 0/) from protons by beams of proton (p), kaon (K), pion (.pi.), and antiproton (antiproton) particles. The experiment used the Fermilab M2 beam line at momenta of 100, 200 and 300 GeV/c striking a liquid hydrogen target. The data include center of mass (cm) production angles of the .pi./sup 0/ between 2/sup 0/ and 115/sup 0/ for P perpendicular to greater than 1 GeV/c. A pair of differential Cherenkov counters distinguished the types of beam particles. The photon (.gamma.) detector of a lead and scintillator sandwich measured both photons from the .pi./sup 0/ .-->. 2.gamma. decay and enabled a reconstruction of the .pi./sup 0/ kinematics. The measurements show several remarkable features distinguishing the production rates for these different beams, including a forward peak in the cm for .pi.p collisions and much less .pi./sup 0/ production at high P perpendicular to in pp than in .pi.p or Kp collisions. A simple parametrization accurately represents the data over most of its range, showing approximate scaling in the radial variable x/sub R/ = 2P/.sqrt.s (in the cm). Several parton models are compared with the data. A heuristic picture in terms of the quark constituents of the interacting hadrons accounts for many features of the data in an intuitive way. 62 references.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
These are the results of a measurement of inclusive production at high transverse momentum (P perpendicular to) of neutral pions (.pi./sup 0/) from protons by beams of proton (p), kaon (K), pion (.pi.), and antiproton (antiproton) particles. The experiment used the Fermilab M2 beam line at momenta of 100, 200 and 300 GeV/c striking a liquid hydrogen target. The data include center of mass (cm) production angles of the .pi./sup 0/ between 2/sup 0/ and 115/sup 0/ for P perpendicular to greater than 1 GeV/c. A pair of differential Cherenkov counters distinguished the types of beam particles. The photon (.gamma.) detector of a lead and scintillator sandwich measured both photons from the .pi./sup 0/ .-->. 2.gamma. decay and enabled a reconstruction of the .pi./sup 0/ kinematics. The measurements show several remarkable features distinguishing the production rates for these different beams, including a forward peak in the cm for .pi.p collisions and much less .pi./sup 0/ production at high P perpendicular to in pp than in .pi.p or Kp collisions. A simple parametrization accurately represents the data over most of its range, showing approximate scaling in the radial variable x/sub R/ = 2P/.sqrt.s (in the cm). Several parton models are compared with the data. A heuristic picture in terms of the quark constituents of the interacting hadrons accounts for many features of the data in an intuitive way. 62 references.
Physics Briefs
Author:
Publisher:
ISBN:
Category : Physics
Languages : en
Pages : 1058
Book Description
Publisher:
ISBN:
Category : Physics
Languages : en
Pages : 1058
Book Description