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We report the laser excitation and dispensed fluorescence spectra of the $MgCH3A~2E\leftarrow X~2A1$ transition. Improvements to the experiment have allowed the observation of important vibronic features not previously observed. The radical was produced in a free jet expansion from the simultaneous photolysis of $Hg(CH3)2$ and the laser vaporization of solid Mg. The use of $Hg(CH3)2$ as a precursor substancially improves production of the radical. A $0.1cm-1$ resolution laser was used to obtain the partially rotationally resolved LIF spectra of the $601$, and $201$ transitions. Analysis of these spectra, along with the previously $reportedg 000$ band yield structural parameters which provide information about the radical’s $A¯2E$ state. Besides the usual rotational constants, we have obtained information about the Jahn-Teller effect, which is dynamic and relatively weak. We have also obtained the values of the Coriolis coupling and the spin-orbit coupling constants. The fluorescence lifetime was found to be 60(7) ns for the vibrationless level of the $A¯$ state and less than 15 ns for transitions involving vibrational excitation. The dispersed fluorescence spectra of the jet-cooled $MgCH3$ was analyzed, and all observed $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}A1$ state vibrational features were assigned.