Measurement of the radiative decay width \Gamma[\Lambda(1520) --> \Lambda \gamma] with the SPHINX spectrometer

TL;DR

This paper reports a direct measurement of the radiative decay width of the mbda(1520) baryon into mbda and a photon using the SPHINX spectrometer, providing new quantitative decay data.

Contribution

The study presents the first direct measurement of the radiative decay width of mbda(1520) with specific branching ratio and partial width values.

Findings

Branching ratio BR[mbda(1520) bla  mbda b3] = (1.02 1 0.21(stat) 1 0.15(syst)) d7 10^{-2}

Decay width mbda(1520)  bla  mbda b3] = 159 1 33(stat) 1 26(syst) keV

The measurement was performed using the SPHINX spectrometer in a diffractive-like reaction setting.

Abstract

The radiative decay \Lambda(1520) --> \Lambda \gamma was measured directly in the study of exclusive diffractive-like reaction p + N --> \Lambda(1520) K^+ + N, \Lambda(1520) --> \Lambda \gamma with the SPHINX spectrometer. The values of the branching and partial width of this radiative decay were obtained: BR[\Lambda(1520) --> \Lambda \gamma] = (1.02+/-0.21(stat)+/-0.15(syst))x10^{-2} and \Gamma[\Lambda(1520) --> \Lambda \gamma] = 159+/-33(stat)+/-26(syst) keV.