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The $A~2A1$ - $\backslash tilde\{X\}\; ^2\{B\}\_1\; \}$ electronic transition of the jet-cooled AsH$2$ free radical has been studied by laser-induced fluorescence (LIF), wavelength-resolved emission, and fluorescence lifetime measurements. The radical was produced by a pulsed electric discharge through a mixture of arsine (AsH$3$) and high-pressure argon at the exit of a pulsed valve. Nine vibronic bands were identified by LIF spectroscopy in the 505-400 nm region, including a long progression in the bending mode and two bands ($101$ and $101$$201$) involving the excited state As-H symmetric stretch. Single vibronic level emission spectra showed similar activity in the bending and symmetric stretching frequencies of the ground state. High- resolution spectra of the $000$ band exhibited large spin-splittings and small, resolved arsenic hyperfine splittings, due to a substantial Fermi contact interaction in the excited state. The rotational constants obtained in the analysis gave effective molecular structures of $r0\prime \prime$ = 1.5183(1) \AA, $\theta 0\prime \prime$ = 90.75(1) and $r0\prime$ = 1.4830(1) \AA, $\theta 0\prime$ = 123.10(2). The excited state fluorescence lifetimes vary dramatically with rovibronic state, from a single value of 1.4 $\mu$s to many with lifetimes less than 10 ns, behavior which we interpret as signaling the onset of a predissociative process in the excited state.