N-to-Δ electromagnetic-transition form factors from lattice QCD -: art. no. 021601

被引：98

作者：

Alexandrou, C ^{[1
]}

de Forcrand, P

Neff, H

Negele, JW

Schroers, W

Tsapalis, A

机构：

[1] Univ Cyprus, Dept Phys, CY-1678 Nicosia, Cyprus

[2] ETH, CH-8093 Zurich, Switzerland

[3] CERN, Div Theory, CH-1211 Geneva 23, Switzerland

[4] Boston Univ, Dept Phys, Boston, MA 02215 USA

[5] MIT, Ctr Theoret Phys, Nucl Sci Lab, Cambridge, MA 02139 USA

[6] MIT, Dept Phys, Cambridge, MA 02139 USA

来源：

PHYSICAL REVIEW LETTERS | 2005年 / 94卷 / 02期

关键词：

D O I：

10.1103/PhysRevLett.94.021601

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The magnetic dipole (M1), the electric quadrupole (E2), and the Coulomb quadrupole (C2) amplitudes for gammaN-->Delta are calculated in quenched lattice QCD. Using a new method, which combines an optimal choice of interpolating fields for the Delta and an overconstrained analysis, we obtain statistically accurate results for the dipole form factor and for the ratios R-EM=E2/M1 and R-SM=C2/M1, up to momentum transfer squared 1.5 GeV2. We show for the first time, using lattice QCD, that both R-EM and R-SM are nonzero and negative, in qualitative agreement with experiment and indicating the presence of deformation in the N/Delta system.

引用

页数：4

共 30 条

[1] PIO ELECTROPRODUCTION AT FIRST RESONANCE AT MOMENTUM-TRANSFERS Q-2=0.6, 1.0 AND 1.56 GEV-2 [J].

ALDER, JC ;

BRASSE, FW ;

CHAZELAS, E ;

MERKWITZ, M ;

MAY, J ;

GAYLER, J ;

GANSSENA.E ;

VALENTIN, J ;

TRISTRAM, G ;

FEHRENBA.W ;

FRANK, KH ;

FLAUGER, W ;

KORBEL, V ;

COURAU, A .

NUCLEAR PHYSICS B, 1972, B 46 (02) :573-&

[2] N to Δ electromagnetic transition form factors from lattice QCD -: art. no. 114506 [J].

Alexandrou, C ;

de Forcrand, P ;

Lippert, T ;

Neff, H ;

Negele, JW ;

Schilling, K ;

Schroers, W ;

Tsapalis, A .

PHYSICAL REVIEW D, 2004, 69 (11)

[3] γN→Δ transition form factors in quenched and NF=2 QCD [J].

Alexandrou, C ;

de Forcrand, P ;

Lippert, T ;

Neff, H ;

Negele, JW ;

Schilling, K ;

Schroers, W ;

Tsapalis, A .

NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS, 2004, 129 :302-304

[4] The matter density distribution for mesons and baryons [J].

Alexandrou, C ;

de Forcrand, P ;

Tsapalis, A .

NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS, 2004, 129 :221-223

[5] Matter and pseudoscalar densities in lattice QCD [J].

Alexandrou, C ;

de Forcrand, P ;

Tsapalis, A .

PHYSICAL REVIEW D, 2003, 68 (07)

[6]

Alexandrou C, 2004, NUCL PHYS B-PROC SUP, V128, P1, DOI [10.1016/S0920-5632(03)02451-4, 10.1016/j.nuclphysbps.2003.12.045]

[7] Hadron wave functions and the issue of nucleon deformation [J].

Alexandrou, C ;

de Forcrand, P ;

Tsapalis, A .

NUCLEAR PHYSICS A, 2003, 721 :907C-910C

[8] Gauge-invariant two- and three- density correlators [J].

Alexandrou, C ;

de Forcrand, P ;

Tsapalis, A .

NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS, 2003, 119 :422-424

[9] Probing hadron wave functions in lattice QCD [J].

Alexandrou, C ;

de Forcrand, P ;

Tsapalis, A .

PHYSICAL REVIEW D, 2002, 66 (09)

[10]

ALEXANDROU C, HEPLAT0408017

← 1 2 3 →