Measurement of the Radiative Width of theK*+(890)

Abstract

Coherent production of Kir systems observed in the excitation of 200-GeV/c positive kaons on nuclear targets has been analyzed, including both electromagnetic and strong contributions, to yield a new value for the radiative width for the process K* + (89Q)-+K + y of 51±5keV.PACS numbers: 13.40.Hq, 14.40.EvRadiative decays of vector mesons present one of the simplest regimes for testing unitary symmetry schemes and quark models of hadrons. In particular, the decay (vector meson) -(pseudoscalar meson) + y, which can be interpreted as a magnetic dipole transition between two quark levels, provides a rather sensitive probe of the symmetry of quark-antiquark systems. Much theoretical work has been devoted to the phenomenology of such decays from the viewpoint of unitary symmetry, simple quark models, and vector-dominance ideas.

Excited meson radiative transitions from lattice QCD using variationally optimized operators

“…The calculation performed here uses three degenerate quark flavors tuned to approximate the physical strange quark mass and as such our photocoupling determination cannot be directly compared with experiment. For orientation we show in Figure 18, the experimental values, F ρπ (0) = 0.33(2) and F K * K (0) = 0.57(3) extracted from the corresponding decay rates obtained via the Primakoff effect for pions and kaons incident on nuclear targets [56][57][58].…”

Meson decays in an extended Nambu—Jona-Lasinio model with heavy quark flavors

“…The strong and radiative decays provide us important information about hadron struc-ture. Experimentally, the decay widths of light vector mesons have been well measured [14][15][16][17][18][19] and so far some of decay widths or ratios of the charmed and bottomed heavy vector mesons were reported [20][21][22].…”

Primakoff production ofπ0,η, andη′in the Coulomb field of a nucleus

“…The Primakoff effect has been observed in the high energy reactions involving the hadronic probes where it was used to measure the radiative decay widths of mesons and baryons. The most important applications of the Primakoff process are the measurements of radiative life times of vector ρ ± (770) [2][3][4][5], K * ± (890) [6][7][8] and axialvector a 1 (1260) [9], b 1 (1235) [10] mesons in the coherent high energy π(K) → meson excitation on nuclear targets. The measurement of the Λ to γΣ 0 transition is another well known example [11,12].…”