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We present the first results from the Small Magellanic Cloud portion of a newAustralia Telescope Compact Array (ATCA) HI absorption survey of both of theMagellanic Clouds, comprising over 800 hours of observations. Our new HIabsorption line data allow us to measure the temperature and fraction of coldneutral gas in a low metallicity environment. We observed 22 separate fields,targeting a total of 55 continuum sources against 37 of which we detected HIabsorption; from this we measure a column density weighted mean average spintemperature of $<T_{s}>=150$ K. Splitting the spectra into individualabsorption line features, we estimate the temperatures of different gascomponents and find an average cold gas temperature of $\sim{30}$ K for thissample, lower than the average of $\sim{40}$ K in the Milky Way. The HI appearsto be evenly distributed throughout the SMC and we detect absorption in $67\%$of the lines of sight in our sample, including some outside the main body ofthe galaxy ($N_{\text{HI}}>2\times{10^{21}}$ cm$^{-2}$). The optical depth andtemperature of the cold neutral atomic gas shows no strong trend with locationspatially or in velocity. Despite the low metallicity environment, we find anaverage cold gas fraction of $\sim{20\%}$, not dissimilar from that of theMilky Way.

An ATCA Survey of HI Absorption in the Magellanic Clouds I: HI Gas Temperature Measurements in the Small Magellanic Cloud