The carbon-enhanced metal-poor star BD + 44 ^ { \circ } 493 ( [ Fe/H ] = - 3.9 ) has been proposed as a candidate second-generation star enriched by metals from a single Pop III star .
We report the first detections of P and S and the second detection of Zn in any extremely metal-poor carbon-enhanced star , using new spectra of BD + 44 ^ { \circ } 493 collected by the Cosmic Origins Spectrograph on the Hubble Space Telescope .
We derive [ P/Fe ] = - 0.34 \pm 0.21 , [ S/Fe ] = + 0.07 \pm 0.41 , and [ Zn/Fe ] = - 0.10 \pm 0.24 .
We increase by ten-fold the number of Si i lines detected in BD + 44 ^ { \circ } 493 , yielding [ Si/Fe ] = + 0.15 \pm 0.22 .
The [ S/Fe ] and [ Zn/Fe ] ratios exclude the hypothesis that the abundance pattern in BD + 44 ^ { \circ } 493 results from depletion of refractory elements onto dust grains .
Comparison with zero-metallicity supernova models suggests that the stellar progenitor that enriched BD + 44 ^ { \circ } 493 was massive and ejected much less than 0.07 M _ { \odot } of ^ { 56 } Ni , characteristic of a faint supernova .