2016ApJ...824L..19R

The carbon-enhanced metal-poor star BD+44°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°493 collected by the Cosmic Origins Spectrograph on the Hubble Space Telescope. We derive [P/Fe]=-0.34±0.21, [S/Fe]=+0.07±0.41, and [Zn/Fe]=-0.10±0.24. We increase by 10-fold the number of Si i lines detected in BD+44°493, yielding [Si/Fe]=+0.15±0.22. The [S/Fe] and [Zn/Fe] ratios exclude the hypothesis that the abundance pattern in BD+44°493 results from depletion of refractory elements onto dust grains. Comparison with zero-metallicity supernova (SN) models suggests that the stellar progenitor that enriched BD+44°493 was massive and ejected much less than 0.07 M_☉ of ⁵⁶Ni, characteristic of a faint SN.