Spectroscopic Study of $\Lambda $ Hypernuclei using the (e,e'K$^{+})$ Reaction

The ``Spectroscopic Study of $\Lambda $ Hypernuclei up to the Medium-Heavy Mass Region Through the (e,e'K$^{+})$ Reaction'' (HKS Experiment) was successfully completed during the summer of 2005 at Jefferson Laboratory. It utilized a new High Resolution Kaon Spectrometer (HKS) and a ``Tilt Method'' to the electron arm aiming to achieve the best ever resolution and the highest possible production yield of $\Lambda $Hypernuclei. The goal of the experiment is to investigate $\Lambda $ hypernuclear structures with precise measurements of the mass spectra from light to medium-heavy mass region. Such precise spectroscopy will provide valuable information on the single-particle behavior of $\Lambda $ hyperon in a nuclear medium, gain knowledge on the effective $\Lambda $-N interaction, and nuclear structure probed by the $\Lambda $ hyperon. An overview of HKS experiment will be presented and preliminary results of the excitation spectra from various targets will be showcased.