First Monte Carlo Global QCD Analysis of Pion Parton Distributions

被引:123
作者
Barry, P. C. [1 ]
Sato, N. [2 ]
Melnitchouk, W.
Ji, Chueng-Ryong [1 ,3 ]
机构
[1] North Carolina State Univ, Raleigh, NC 27607 USA
[2] Univ Connecticut, Storrs, CT 06269 USA
[3] Jefferson Lab, Newport News, VA 23606 USA
关键词
GENERAL BAYESIAN COMPUTATION; LEADING NEUTRON-PRODUCTION; DRELL-YAN; NUCLEON; MODEL; COLLISIONS; BREAKING; TUNGSTEN; MESONS; HERA;
D O I
10.1103/PhysRevLett.121.152001
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
We perform the first global QCD analysis of parton distribution functions (PDFs) in the pion, combining pi A Drell-Yan data with leading neutron electroproduction from HERA within a Monte Carlo approach based on nested sampling. Inclusion of the HERA data allows the pion PDFs to be determined down to much lower values of x, with relatively weak model dependence from uncertainties in the chiral splitting function. The combined analysis reveals that gluons cany a significantly higher pion momentum fraction, similar to 30%, than that inferred from Drell-Yan data alone, with sea quarks carrying a somewhat smaller fraction, similar to 15%, at the input scale. Within the same effective theory framework, the chiral splitting function and pion PDFs can be used to describe the (d) over bar - (u) over bar asymmetry in the proton.
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页数:6
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共 59 条
[1]   Measurement of leading neutron production in deep-inelastic scattering at HERA [J].
Aaron, F. D. ;
Alexa, C. ;
Andreev, V. ;
Antunovic, B. ;
Backovic, S. ;
Baghdasaryan, A. ;
Barrelet, E. ;
Bartel, W. ;
Begzsuren, K. ;
Belousov, A. ;
Bizot, J. C. ;
Boudry, V. ;
Bozovic-Jelisavcic, I. ;
Bracinik, J. ;
Brandt, G. ;
Brinkmann, M. ;
Brisson, V. ;
Bruncko, D. ;
Bunyatyan, A. ;
Buschhorn, G. ;
Bystritskaya, L. ;
Campbell, A. J. ;
Avila, K. B. Cantun ;
Cerny, K. ;
Cerny, V. ;
Chekelian, V. ;
Cholewa, A. ;
Contreras, J. G. ;
Coughlan, J. A. ;
Cozzika, G. ;
Cvach, J. ;
Dainton, J. B. ;
Daum, K. ;
Deak, M. ;
Delcourt, B. ;
Delvax, J. ;
De Wolf, E. A. ;
Diaconu, C. ;
Dodonov, V. ;
Dossanov, A. ;
Dubak, A. ;
Eckerlin, G. ;
Efremenko, V. ;
Egli, S. ;
Eliseev, A. ;
Elsen, E. ;
Falkiewicz, A. ;
Favart, L. ;
Fedotov, A. ;
Felst, R. .
EUROPEAN PHYSICAL JOURNAL C, 2010, 68 (3-4) :381-399
[2]   Soft-Gluon Resummation and the Valence Parton Distribution Function of the Pion [J].
Aicher, Matthias ;
Schaefer, Andreas ;
Vogelsang, Werner .
PHYSICAL REVIEW LETTERS, 2010, 105 (25)
[3]   Dilepton rapidity distribution in the Drell-Yan process at next-to-next-to-leading order in QCD [J].
Anastasiou, C ;
Dixon, L ;
Melnikov, K ;
Petriello, F .
PHYSICAL REVIEW LETTERS, 2003, 91 (18)
[4]  
Annand J., E1215006 JEFF LAB
[5]  
[Anonymous], 2008, J HIGH ENERGY PHYS
[6]   Chiral corrections to matrix elements of twist-2 operators [J].
Arndt, D ;
Savage, MJ .
NUCLEAR PHYSICS A, 2002, 697 (1-2) :429-439
[7]   THE GLUON CONTENT OF THE PION FROM HIGH-PT DIRECT PHOTON PRODUCTION [J].
AURENCHE, P ;
BAIER, R ;
FONTANNAZ, M ;
KIENZLEFOCACCI, MN ;
WERLEN, M .
PHYSICS LETTERS B, 1989, 233 (3-4) :517-521
[8]  
BADIER J, 1983, Z PHYS C PART FIELDS, V18, P281, DOI 10.1007/BF01573728
[9]  
Barry P. C., IN PRESS
[10]   QUARK STRUCTURE FUNCTIONS OF MESONS AND THE DRELL-YAN PROCESS [J].
BERGER, EL ;
BRODSKY, SJ .
PHYSICAL REVIEW LETTERS, 1979, 42 (15) :940-944