  The majority of molecules proposed for laser cooling and trapping experiments
have $\Sigma$-type ground states. Specifically, $^2\Sigma$ states have cycling
transitions analogous to D1-lines in alkali-metal atoms while $^1\Sigma$ states
offer both strong and weak cycling transitions analogous to those in
alkaline-earth atoms. Despite this proposed variety, to date, only molecules
with $^2\Sigma$-type ground states have successfully been confined and cooled
in magneto-optical traps. While none of the proposed $^1\Sigma$-type molecules
have been successfully laser cooled and trapped, they are expected to have
various advantages in terms of exhibiting a lower chemical reactivity and an
internal structure that benefits the cooling schemes. Here, we present the
prospects and strategies for optical cycling in AlCl -- a $^1\Sigma$ molecule
-- and report on the characterization of the $A^{1}\Pi$ state hyperfine
structure. Based on these results, we carry out detailed simulations on the
expected capture velocity of a magneto-optical trap for AlCl. Finally, using
{\it ab initio} calculations, we identify the photodissociation via a $3^1\Pi$
state and photoionization process via the $3^1\Sigma^+$ state as possible loss
mechanisms for a magneto-optical trap of AlCl.

Atomic Physics