Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Charged Pion Cross Sections And Double Helicity Asymmetries In Polarized P P Collisions At S
Download Charged Pion Cross Sections And Double Helicity Asymmetries In Polarized P P Collisions At S full books in PDF, epub, and Kindle. Read online Charged Pion Cross Sections And Double Helicity Asymmetries In Polarized P P Collisions At S ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Charged-pion Cross Sections and Double-helicity Asymmetries in Polarized P+p Collisions at S by :
Download or read book Charged-pion Cross Sections and Double-helicity Asymmetries in Polarized P+p Collisions at S written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper, we present midrapidity charged-pion invariant cross sections, the ratio of the ?- to ?+ cross sections and the charge-separated double-spin asymmetries in polarized p+p collisions at s=200 GeV. While the cross section measurements are consistent within the errors of next-to-leading-order (NLO) perturbative quantum chromodynamics predictions (pQCD), the same calculations overestimate the ratio of the charged-pion cross sections. This discrepancy arises from the cancellation of the substantial systematic errors associated with the NLO-pQCD predictions in the ratio and highlights the constraints these data will place on flavor-dependent pion fragmentation functions. Lastly, the charge-separated pion asymmetries presented here sample an x range of 0̃.03–0.16 and provide unique information on the sign of the gluon-helicity distribution.
Book Synopsis Charged-pion Cross Sections and Double-helicity Asymmetries in Polarized [math Display by :
Download or read book Charged-pion Cross Sections and Double-helicity Asymmetries in Polarized [math Display written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper, we present midrapidity charged-pion invariant cross sections, the ratio of the [pi]- to [pi]+ cross sections and the charge-separated double-spin asymmetries in polarized p+p collisions at s=200 GeV. While the cross section measurements are consistent within the errors of next-to-leading-order (NLO) perturbative quantum chromodynamics predictions (pQCD), the same calculations overestimate the ratio of the charged-pion cross sections. This discrepancy arises from the cancellation of the substantial systematic errors associated with the NLO-pQCD predictions in the ratio and highlights the constraints these data will place on flavor-dependent pion fragmentation functions. Lastly, the charge-separated pion asymmetries presented here sample an x range of ~0.03-0.16 and provide unique information on the sign of the gluon-helicity distribution.
Book Synopsis Measurement of Double Longitudinal Spin Asymmetry of Jet-[pi] +/- Correlations in Polarized Proton-proton Collisions at [square Root Of] S by : James Prewitt Hays-Wehle
Download or read book Measurement of Double Longitudinal Spin Asymmetry of Jet-[pi] +/- Correlations in Polarized Proton-proton Collisions at [square Root Of] S written by James Prewitt Hays-Wehle and published by . This book was released on 2013 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inclusive measurements from polarized proton-proton collisions at RHIC have constrained [Delta]g, the polarized gluon distribution function of the proton. Correlation observables, such as this pion+jet measurement, allow for reconstruction of initial parton kinematics and are thus sensitive to the x dependence of [Delta]g. By measuring charged pions opposite a jet, this particular measurement can be sensitive to the flavor of the struck parton. This measurement, which is dominated by the quark-gluon subprocess, can be divided into terms proportional to [Delta]u[Delta]g and [Delta]d[Delta]g. The relatively larger quark polarization amplifies the measured asymmetry thereby enhancing the statistical power. This thesis presents the result of the mid-rapidity pion+jet longitudinal double spin asymmetry analysis from 10.6 pb-1 of luminosity collected in the 2009 200 GeV p+p run.
Book Synopsis Beam-Helicity Asymmetries in Double-Charged-Pion Photoproduction on the Proton by :
Download or read book Beam-Helicity Asymmetries in Double-Charged-Pion Photoproduction on the Proton written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Beam-helicity asymmetries for the two-pion-photoproduction reaction gamma + p --> p pi+ pi- have been studied for the first time in the resonance region for center-of-mass energies between 1.35 GeV and 2.30 GeV. The experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer using circularly polarized tagged photons incident on an unpolarized hydrogen target. Beam-helicity-dependent angular distributions of the final-state particles were measured. The large cross-section asymmetries exhibit strong sensitivity to the kinematics and dynamics of the reaction. The data are compared with the results of various phenomenological model calculations, and show that these models currently do not provide an adequate description for the behavior of this new observable.
Book Synopsis Neutral Pion Double Helicity Asymmetry in Polarized Proton-Proton Collisions at [the Square Root of Sigma] by : William Axel Leight
Download or read book Neutral Pion Double Helicity Asymmetry in Polarized Proton-Proton Collisions at [the Square Root of Sigma] written by William Axel Leight and published by . This book was released on 2012 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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].
Book Synopsis Measurement of Longitudinal Double Spin Asymmetries of [pi]+/- Production in P[over-arrow] + P[over-arrow] Collisions at [sqrt]s by : Adam Philip Kocoloski
Download or read book Measurement of Longitudinal Double Spin Asymmetries of [pi]+/- Production in P[over-arrow] + P[over-arrow] Collisions at [sqrt]s written by Adam Philip Kocoloski and published by . This book was released on 2010 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis Longitudinal Double-spin Asymmetry and Cross Section for Inclusive Neutral Pion Production in Polarized Proton Collisions at [the Square Root of Sigma] by : Alan Michael Hoffman
Download or read book Longitudinal Double-spin Asymmetry and Cross Section for Inclusive Neutral Pion Production in Polarized Proton Collisions at [the Square Root of Sigma] written by Alan Michael Hoffman and published by . This book was released on 2009 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Twenty years of polarized lepton-nucleon scattering experiments have found that the contribution from quark spins (1/2[delta] [sigma]) to the spin of the proton is only ~ 35%. This has lead researchers to look elsewhere, specifically to gluon spin ([delta sigma]) for a large contribution to proton spin. [delta sigma] has been only loosely constrained in polarized DIS and SIDIS experiments. Polarized proton-proton collisions at RHIC provide sensitivity to [delta sigma] through measurements of the longitudinal double-spin asymmetry, ALL. This work presents a measurement of ALL for inclusive 7ro production in polarized proton-proton collisions using the STAR detector and data from RHIC Run 6. 7r0s are abundantly produced at mid-rapidity in proton-proton collisions, making them natural candidates for studies of [delta] [sigma]. Novel techniques for reconstructing 7ros at STAR are discussed, and a measurement of the unpolarized cross section presented. Finally, the measured ALL is compared to perturbative QCD predictions and from this comparison constraints are placed on [delta] [sigma].
Book Synopsis Inclusive Cross Section and Double-helicity Asymmetry for [math Display by :
Download or read book Inclusive Cross Section and Double-helicity Asymmetry for [math Display written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present PHENIX measurements for the cross section and double-helicity asymmetry (ALL) in inclusive [pi]0 production at midrapidity from p + p collisions at √s = 510 GeV from data taken in 2012 and 2013 at the Relativistic Heavy Ion Collider. The next-to-leading-order perturbative-quantum-chromodynamics theory calculation is in excellent agreement with the presented cross section results. The calculation utilized parton-to-pion fragmentation functions from the recent DSS14 global analysis, which prefer a smaller gluon-to-pion fragmentation function. Our [pi]0ALL results follow an increasingly positive asymmetry trend with pT and √s with respect to the predictions and are in excellent agreement with the latest global analysis results. This analysis incorporated earlier results on [pi]0 and jet ALL and suggested a positive contribution of gluon polarization to the spin of the proton [Delta]G for the gluon momentum fraction range x > 0.05. Finally, the data presented here extend to a currently unexplored region, down to x similar to 0.01, and thus provide additional constraints on the value of [Delta]G.
Book Synopsis Measurements of the W Boson Rapidity, Helicity, Double-differential Cross Sections, and Charge Asymmetry in Pp Collisions at √s by : Albert M. Sirunyan
Download or read book Measurements of the W Boson Rapidity, Helicity, Double-differential Cross Sections, and Charge Asymmetry in Pp Collisions at √s written by Albert M. Sirunyan and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Measurements of the Double Helicity Asymmetry in Pion Production in Proton Collisions at [square Root Of] by :
Download or read book Measurements of the Double Helicity Asymmetry in Pion Production in Proton Collisions at [square Root Of] written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Longitudinal Double-spin Asymmetry and Cross Section for Inclusivejet Production in Polarized Proton Collisions at Sqrt(s) by :
Download or read book Longitudinal Double-spin Asymmetry and Cross Section for Inclusivejet Production in Polarized Proton Collisions at Sqrt(s) written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report a measurement of the longitudinal double-spinasymmetry A_LL and the differential cross section for inclusivemidrapidity jet production in polarized proton collisions at sqrt(s)=200GeV. The cross section data cover transverse momenta 5
Book Synopsis The Spin Structure of the Proton by : Steven D. Bass
Download or read book The Spin Structure of the Proton written by Steven D. Bass and published by World Scientific. This book was released on 2008 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the main challenges in nuclear and particle physics in the last 20 years has been to understand how the proton''s spin is built up from its quark and gluon constituents. Quark models generally predict that about 60% of the proton''s spin should be carried by the spin of the quarks inside, whereas high energy scattering experiments have shown that the quark spin contribution is small OCo only about 30%. This result has been the underlying motivation for about 1000 theoretical papers and a global program of dedicated spin experiments at BNL, CERN, DESY and Jefferson Laboratory to map the individual quark and gluon angular momentum contributions to the proton''s spin, which are now yielding exciting results. This book gives an overview of the present status of the field: what is new in the data and what can be expected in the next few years. The emphasis is on the main physical ideas and the interpretation of spin data. The interface between QCD spin physics and the famous axial U(1) problem of QCD (eta and etaprime meson physics) is also highlighted. Sample Chapter(s). Chapter 1: Introduction (159 KB). Contents: Spin Experiments and Data; Dispersion Relations and Spin Sum Rules; g 1 Spin Sum Rules; Fixed Poles; The Axial Anomaly, Gluon topology and g (0) A; Chiral Symmetry and Axial U(1) Dynamics; QCD Inspired Models of the Proton Spin Problem; The Spin-Flavour Structure of the Proton; QCD Fits to g 1 Data; Polarized Quark Distributions; Polarized Glue o g(x, Q 2 ); Transversity; Deeply Virtual Compton Scattering and Exclusive Processes; Polarized Photon Structure Functions; Conclusions and Open Questions: How Does the Proton Spin?. Readership: Academics, as well as physicists working on particle and nuclear physics at the interface of theory and experiment.
Book Synopsis W Boson Cross Sections and Single Spin Asymmetries in Polarized Proton-proton Collisions at [square Root Of] S by : Ross Cameron Corliss
Download or read book W Boson Cross Sections and Single Spin Asymmetries in Polarized Proton-proton Collisions at [square Root Of] S written by Ross Cameron Corliss and published by . This book was released on 2012 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the structure of the proton is an ongoing effort in the particle physics community. Existing in the region of nonperturbative QCD, the various models for proton structure must be informed and constrained by experimental data. In 2009, the STAR experiment at Brookhaven National Lab recorded over 12 pb-1 of data from polarized p+p collisions at 500 GeV center-of-mass energy provided by the RHIC accelerator. This has offered a first look at the spin-dependent production of W+(-) bosons, and hence at the spin-flavor structure of the proton, where the main production mode is through d+u (u+d) annihilation. Using STAR's large Time Projection Chamber and its wide-acceptance electromagnetic calorimeters, it is possible to identify the e+ + v (e- + v) decay mode of the W bosons produced. This thesis presents the first STAR measurement of charge-separated W production, both the pseudorapidity-dependent ratio and the longitudinal single-spin asymmetry. These results show good agreement with theoretical expectations, validating the methods used and paving the way for the analysis of larger datasets that will be available soon. In the near future the range of this measurement will be augmented with the Forward GEM Tracker. A discussion of the design and implementation of this upgrade is also included, along with projections for its impact.
Book Synopsis Helicity-Dependent Angular Distributions for Double-Charged-Pion Photoproduction by :
Download or read book Helicity-Dependent Angular Distributions for Double-Charged-Pion Photoproduction written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-pion photoproduction in the reaction [rvec [gamma]]p [yields] p[pi][sup +][pi][sup -] has been studied at Jefferson Lab Hall B using a circularly-polarized tagged photon beam in the energy range between 0.6 GeV and 2.3 GeV. Beam-helicity-dependent angular distributions of the final-state particles were measured. The large cross-section asymmetries that have been found exhibit strong sensitivity to the kinematics of the reaction, and are compared with preliminary model calculations by Mokeev and Roberts.
Book Synopsis Inclusive Jet and Dijet Production in Polarized Proton-proton Collisions at [the Square Root of Sigma] by : Tai Sakuma
Download or read book Inclusive Jet and Dijet Production in Polarized Proton-proton Collisions at [the Square Root of Sigma] written by Tai Sakuma and published by . This book was released on 2010 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The inclusive jet cross section, the dijet cross section, and the dijet longitudinal double spin asymmetry ALL in polarized proton-proton collisions at [square root of sigma] = 200 GeV are measured with a data sample of 5.4 pbm collected with the STAR detector during RHIC Run-6. The inclusive cross section is measured as a function of jet transverse momentum PT in the range of 10
Book Synopsis Beam-Target Double Spin Asymmetry A[sub]LT[/sub] in Charged Pion Production from Deep Inelastic Scattering on a Transversely Polarized [sup]3[/sup]He Target at 1.4[Q[sup]2[/sup][2.7 GeV[sup]2[/sup]. by :
Download or read book Beam-Target Double Spin Asymmetry A[sub]LT[/sub] in Charged Pion Production from Deep Inelastic Scattering on a Transversely Polarized [sup]3[/sup]He Target at 1.4[Q[sup]2[/sup][2.7 GeV[sup]2[/sup]. written by and published by . This book was released on 2012 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the first measurement of the double-spin asymmetry ALT for charged pion electroproduction in semi-inclusive deep inelastic electron scattering on a transversely polarized 3He target. The kinematics focused on the valence quark region, 0.16 x 0.35 with 1.4 Qsup2/sup 2.7 GeVsup2/sup. The corresponding neutron AsubLT/sub asymmetries were extracted from the measured sup3/supHe asymmetries and proton/sup3/supHe cross section ratios using the effective polarization approximation. These new data probe the transverse momentum dependent parton distribution function gsub 1T/subsupq/sup and therefore provide access to quark spin-orbit correlations. Our results indicate a positive azimuthal asymmetry for?sup-
Author :National Aeronautics and Space Administration (NASA) Publisher :Createspace Independent Publishing Platform ISBN 13 :9781720657910 Total Pages :86 pages Book Rating :4.6/5 (579 download)
Book Synopsis Parameterized Cross Sections for Pion Production in Proton-Proton Collisions by : National Aeronautics and Space Administration (NASA)
Download or read book Parameterized Cross Sections for Pion Production in Proton-Proton Collisions written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-03 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: An accurate knowledge of cross sections for pion production in proton-proton collisions finds wide application in particle physics, astrophysics, cosmic ray physics, and space radiation problems, especially in situations where an incident proton is transported through some medium and knowledge of the output particle spectrum is required when given the input spectrum. In these cases, accurate parameterizations of the cross sections are desired. In this paper much of the experimental data are reviewed and compared with a wide variety of different cross section parameterizations. Therefore, parameterizations of neutral and charged pion cross sections are provided that give a very accurate description of the experimental data. Lorentz invariant differential cross sections, spectral distributions, and total cross section parameterizations are presented.Blattnig, Steve R. and Swaminathan, Sudha R. and Kruger, Adam T. and Ngom, Moussa and Norbury, John W. and Tripathi, R. K.Langley Research CenterPIONS; SCATTERING CROSS SECTIONS; PARTICLE PRODUCTION; PROTONS; PARTICLE COLLISIONS; PROTON-PROTON REACTIONS; SPECTRA; PARAMETERIZATION; EXTRATERRESTRIAL RADIATION; COSMIC RAYS; ASTROPHYSICS
![Download Measurement of Double Longitudinal Spin Asymmetry of Jet-[pi] +/- Correlations in Polarized Proton-proton Collisions at [square Root Of] S PDF Online Free](https://books.google.com/books/content/images/frontcover/5hNWnwEACAAJ?fife=w200-h370)
![Download Neutral Pion Double Helicity Asymmetry in Polarized Proton-Proton Collisions at [the Square Root of Sigma] PDF Online Free](https://books.google.com/books/content/images/frontcover/JPIHlwEACAAJ?fife=w200-h370)
![Download Measurement of Longitudinal Double Spin Asymmetries of [pi]+/- Production in P[over-arrow] + P[over-arrow] Collisions at [sqrt]s PDF Online Free](https://books.google.com/books/content/images/frontcover/fGvpZwEACAAJ?fife=w200-h370)
![Download Longitudinal Double-spin Asymmetry and Cross Section for Inclusive Neutral Pion Production in Polarized Proton Collisions at [the Square Root of Sigma] PDF Online Free](https://books.google.com/books/content/images/frontcover/ZBvxSAAACAAJ?fife=w200-h370)
![Download Measurements of the Double Helicity Asymmetry in Pion Production in Proton Collisions at [square Root Of] PDF Online Free](https://books.google.com/books/content/images/frontcover/EVahDAEACAAJ?fife=w200-h370)
![Download W Boson Cross Sections and Single Spin Asymmetries in Polarized Proton-proton Collisions at [square Root Of] S PDF Online Free](https://books.google.com/books/content/images/frontcover/BdzsoAEACAAJ?fife=w200-h370)
![Download Inclusive Jet and Dijet Production in Polarized Proton-proton Collisions at [the Square Root of Sigma] PDF Online Free](https://books.google.com/books/content/images/frontcover/HZS8ZwEACAAJ?fife=w200-h370)
![Download Beam-Target Double Spin Asymmetry A[sub]LT[/sub] in Charged Pion Production from Deep Inelastic Scattering on a Transversely Polarized [sup]3[/sup]He Target at 1.4[Q[sup]2[/sup][2.7 GeV[sup]2[/sup]. PDF Online Free](https://books.google.com/books/content/images/frontcover/rtr1wQEACAAJ?fife=w200-h370)
