Cross Sections and Beam Asymmetries for K+ Sigma*- photoproduction from the deuteron at 1.5-2.4 GeV

Abstract

The $\Sigma(1385)$ resonance, or $\Sigma^*$, is well-known as part of the standard baryon decuplet with spin $J=3/2$. Measurements of the reaction $\gamma p \to K^+ \Sigma^{*0}$ are difficult to extract due to overlap with the nearby $\Lambda(1405)$ resonance. However, the reaction $\gamma n \to K^+ \Sigma^{*-}$ has no overlap with the $\Lambda(1405)$ due to its charge. Here we report the first measurement of cross sections and beam asymmetries for photoproduction of the \sigs from a deuteron target. % where the $K^+$ and $\pi^-$ are detected in the LEPS spectrometer. The cross sections at forward angles range from 0.4 to 1.2 $\mu$b, with a broad maximum near $E_\gamma \simeq 1.8$ GeV. The beam asymmetries are negative, in contrast to postive values for the $\gamma n \to K^+\Sigma^-$ reaction.