High Resolution Hypernuclear Spectroscopy at Jefferson Lab Hall A

TL;DR

This paper reports high-resolution hypernuclear spectroscopy experiments at Jefferson Lab, revealing new spectral features and precise binding energies for various hypernuclei, advancing understanding of hypernuclear structure.

Contribution

First measurements of core-excited states and high-quality spectra for several hypernuclei, with improved energy resolution and calibration, providing new data for hypernuclear physics.

Findings

Measurable strength in the core-excited spectrum of $^{12}_{\Lambda}B$

First high-quality spectrum of $^{16}_{\Lambda}N$ with sub-MeV resolution

Precise $\Lambda$ binding energy for $^{16}_{\Lambda}N$

Abstract

The characteristics of the Jefferson Lab electron beam, together with those of the experimental equipment, offer a unique opportunity to study hypernuclear spectroscopy via electromagnetic induced reactions. Experiment 94-107 started a systematic study on 1p-shell targets, $^{12}C$, $^{9}Be$ and $^{16}O$. For $^{12}C$ for the first time measurable strength in the core-excited part of the spectrum between the ground state and the p state was shown in $^{12}_{\Lambda}B$ spectrum. A high-quality $^{16}_{\Lambda}N$ spectrum was produced for the first time with sub-MeV energy resolution. A very precise $\Lambda$ binding energy value for $^{16}_{\Lambda}N$, calibrated against the elementary $(e,e'K^+)$ reaction on hydrogen, has also been obtained. $^{9}_{\Lambda}Li$ spectrum shows some disagreement in strength for the second and third doublet with respect to the theory.