Knowledge Bank

A gas phase study of the $\mathrm{<mrow\; data-mjx-texclass="ORD">4</mrow>}\Gamma 2.5$ - A$\mathrm{<mrow\; data-mjx-texclass="ORD">4</mrow>}\Phi 1.5$ (0, 0) band in the astrophysically important titanium hydride molecule, TiH, has recently been undertaken. Low resolution dispersed fluorescence spectra of TiH and TiD have yielded information on the vibrational structure. A high resolution study at a linewidth of $\approx$40 MHz has shown doubling due to resolved hydrogen hyperfine structure in the main $\mathrm{<mrow\; data-mjx-texclass="ORD">48</mrow>}$TiH (74% abundance) isotopologue, and the much weaker $\mathrm{<mrow\; data-mjx-texclass="ORD">46</mrow>}$TiH (8%) and $\mathrm{<mrow\; data-mjx-texclass="ORD">50</mrow>}$TiH (5%) species. Titanium hyperfine structure was also resolved in the weak $\mathrm{<mrow\; data-mjx-texclass="ORD">47</mrow>}$TiH (8%, I = 2.5) and $\mathrm{<mrow\; data-mjx-texclass="ORD">49</mrow>}$TiH (5%, I = 3.5) isotopologues. The magnetic tuning properties of TiH have been examined by studying the Zeeman effect on the low-J lines. The analysis is presently in progress and the latest results will be presented at the symposium.