High Resolution Spectroscopic Study of $^{10}_{\Lambda}$Be

TL;DR

This study used high-resolution spectroscopy at JLab to precisely measure the energy levels of the $^{10}_{\Lambda}$Be hypernucleus, providing new insights into charge symmetry breaking in the $\Lambda N$ interaction.

Contribution

It presents the first high-resolution spectroscopic measurement of $^{10}_{\Lambda}$Be using a novel spectrometer system, improving the precision of hypernuclear energy level determinations.

Findings

Ground state binding energy measured as 8.55 MeV

Ground state energy shallower than previous emulsion studies by about 0.5 MeV

Provides experimental data on charge symmetry breaking in $\Lambda N$ interaction

Abstract

Spectroscopy of a $^{10}_{\Lambda}$Be hypernucleus was carried out at JLab Hall C using the $(e,e^{\prime}K^{+})$ reaction. A new magnetic spectrometer system (SPL+HES+HKS), specifically designed for high resolution hypernuclear spectroscopy, was used to obtain an energy spectrum with a resolution of 0.78 MeV (FWHM). The well-calibrated spectrometer system of the present experiment using the $p(e,e^{\prime}K^{+})\Lambda,\Sigma^{0}$ reactions allowed us to determine the energy levels, and the binding energy of the ground state peak (mixture of 1$^{-}$ and 2$^{-}$ states) was obtained to be B$_{\Lambda}$=8.55$\pm$0.07(stat.)$\pm$0.11(sys.) MeV. The result indicates that the ground state energy is shallower than that of an emulsion study by about 0.5 MeV which provides valuable experimental information on charge symmetry breaking effect in the $\Lambda N$ interaction.