The mass of the vector-meson and the slope of the forward differential cross section in the photo-production process

When tunneling events induced by nontrivial configurations of the quantum chromodynamics gauge fields are taken into consideration, parity violating quantities emerge. Based on this consideration, parity-odd fragmentation functions can be introduced in the high energy reactions. In this paper, we calculate the differential cross-section in terms of both the parity-even and parity-odd fragmentation functions in semi-inclusive electron positron annihilation process. Semi-inclusive implies that not only a vector meson in one jet but also the back-to-back jet is measured in this reaction. According to the differential cross-section, we further calculate the azimuthal asymmetries and hadron polarizations in terms of fragmentation functions. A method of measuring the parity violating effects in the semi-inclusive annihilation process is suggested.

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VECTOR MESON PRODUCTION ABOVE THE RESONANCE REGION

International Journal of Modern Physics A ◽

10.1142/s0217751x0502330x ◽

2005 ◽

Vol 20 (08n09) ◽

pp. 1765-1771

Author(s):

◽

MARCO BATTAGLIERI

Keyword(s):

Differential Cross Section ◽

Vector Meson ◽

Cross Section ◽

Differential Cross ◽

Degrees Of Freedom ◽

Meson Production ◽

Resonance Region ◽

Kinematic Range ◽

Vector Meson Production

The total and differential cross section for exclusive vector meson electro- and photoproduction above the resonance region (2<W<3 GeV ) were measured at Jefferson Laboratory covering a wide kinematic range (0<Q2<5 GeV 2/c2 and 0<-t<5 GeV 2). These measurements provide a unique tool to investigate the transition between soft and hard physics. Our data indicates that this regime can be successfully and consistently described by using the so called effective partonic degrees of freedom.

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On the differential cross section and the slope of vector meson electroproduction

Nuclear Physics B ◽

10.1016/0550-3213(75)90283-7 ◽

1975 ◽

Vol 88 (2) ◽

pp. 301-317 ◽

Cited By ~ 21

Author(s):

H. Fraas ◽

B.J. Read ◽

D. Schildknecht

Keyword(s):

Differential Cross Section ◽

Vector Meson ◽

Cross Section ◽

Differential Cross ◽

Meson Electroproduction

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Study of nucleon resonances in the photoproduction γp → K*+Λ

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194514602452 ◽

2014 ◽

Vol 29 ◽

pp. 1460245

Author(s):

Sang-Ho Kim ◽

Atsushi Hosaka ◽

Hyun-Chul Kim

Keyword(s):

Theoretical Analysis ◽

Differential Cross Section ◽

Vector Meson ◽

Cross Section ◽

Differential Cross ◽

Lagrangian Method ◽

Proton Target ◽

Meson Photoproduction ◽

Nucleon Resonances ◽

Effective Lagrangian

The mechanism of K* vector meson photoproduction off the proton target, γp → K*+Λ, is deeply studied by using an effective Lagrangian method. Based on the (t,s,u)-channel Born diagrams, we included higher resonance terms, i.e., S11(2090) and G17(2190), along with the D13(2080) and D15(2200), which are already considered in a previous theoretical analysis. The total and differential cross section are computed and we obtain quite precise results in comparison with the recent CLAS data.

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