  We report Zn abundances for 18 very metal-poor stars studied in our previous
work, covering the metallicity range -3.2 < [Fe/H] < -2.5. The [Zn/Fe] values
of most stars show an increasing trend with decreasing [Fe/H] in this
metallicity range, confirming the results found by previous studies. However,
the extremely metal-poor star BS 16920-017 ([Fe/H] = -3.2) exhibits a
significantly high [Zn/Fe] ratio ([Zn/Fe] = +1.0). Comparison of the chemical
abundances of this object with HD 4306, which has similar atmospheric
parameters to BS 16920-017, clearly demonstrates a deficiency of alpha elements
and neutron-capture elements in this star, along with enhancements of Mn and
Ni, as well as Zn. The association with a hypernova explosion that has been
proposed to explain the high Zn abundance ratios found in extremely metal-poor
stars is a possible explanation, although further studies are required to fully
interpret the abundance pattern of this object.
