Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Pion form factor in QCD at intermediate momentum transfers - art. no. 073004
Autore:
Braun, VM; Khodjamirian, A; Maul, M;
Indirizzi:
Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany Univ Regensburg Regensburg Germany D-93040 , D-93040 Regensburg, Germany Univ Wurzburg, Inst Theoret Phys, D-97074 Wurzburg, Germany Univ WurzburgWurzburg Germany D-97074 t Phys, D-97074 Wurzburg, Germany NORDITA, DK-2100 Copenhagen, Denmark NORDITA Copenhagen Denmark DK-2100NORDITA, DK-2100 Copenhagen, Denmark
Titolo Testata:
PHYSICAL REVIEW D
fascicolo: 7, volume: 6107, anno: 2000,
pagine: 3004 -
SICI:
0556-2821(20000401)6107:7<3004:PFFIQA>2.0.ZU;2-W
Fonte:
ISI
Lingua:
ENG
Soggetto:
SUM-RULES; QUANTUM CHROMODYNAMICS; EXCLUSIVE PROCESSES; PERTURBATIVE QCD; DISTRIBUTION AMPLITUDE; RADIATIVE-CORRECTIONS; EVOLUTION-EQUATIONS; ASYMPTOTIC-BEHAVIOR; TRANSVERSE-MOMENTUM; NONLEADING TWIST;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
--discip_EC--
Citazioni:
66
Recensione:
Indirizzi per estratti:
Indirizzo: Braun, VM Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany Univ Regensburg Regensburg Germany D-93040 Regensburg, Germany
Citazione:
V.M. Braun et al., "Pion form factor in QCD at intermediate momentum transfers - art. no. 073004", PHYS REV D, 6107(7), 2000, pp. 3004

Abstract

We present a quantitative analysis of the electromagnetic pion form factorin the light-cone sum rule approach, including radiative corrections and higher-twist effects. The comparison to the existing data favors the asymptotic profile of the pion distribution amplitude and allows us to estimate the deviation: [integral dulu phi(pi)(u)]/[integral dulu phi(pi)(as)(u)] = 1.1+/- 0.1 at the scale of 1 GeV. Special attention is paid to the precise definition and interplay of soft and hard contributions at intermediate momentum transfer, and to the matching of the sum rule to the perturbative QCD prediction. We observe a strong numerical cancellation between the soft (end-point) contribution and power-suppressed hard contributions of higher twist, so that the total nonperturbative correction to the usual PQCD result turns out to be of the order of 30% for Q(2) similar to 1 GeV2.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 09/04/20 alle ore 07:42:11