Separated flow operation of the SHARAQ spectrometer for in-flight proton decay experiments

Abstract

New operation mode, "separated flow mode", has been developed for in-flight proton decay experiments with the SHARAQ spectrometer. In the separated flow mode, the protons and the heavy-ion products are separated and measured in coincidence at two different focal planes of SHARAQ. The ion-optical properties of the new mode were studied by using a proton beam at $246\mathrm{MeV}$, and the momentum vector was properly reconstructed from the parameters measured in the focal plane of SHARAQ. In the experiment with the $({}^{16}\mathrm{O},{}^{16}\mathrm{F})$ reaction at a beam energy of $247MeV/u$, the outgoing ${}^{15}\mathrm{O}+p$ produced by the decay of ${}^{16}\mathrm{F}$ were measured in coincidence with SHARAQ. High energy resolutions of $100\mathrm{keV}$ (FWHM) and $\sim 2\mathrm{MeV}$ were achieved for the relative energy of $535\mathrm{keV}$, and the ${}^{16}\mathrm{F}$ energy of $3940\mathrm{MeV}$, respectively.

16 pages, 10 figures, submitted to Nucl. Instrum. Methods Phys. Res. A