Mon. Not. R. Astron. Soc. 000, 1{?? (2001) Printed 22 May 2002 (MN L A T E X style

Analyses of the abundances of neutron-capture elements have led to the belief that these elements in metal-poor stars are r-process products with relative abundances closely resembling those found in the solar system. This picture was challenged by Magain (1995), who found that a pure r-process mix of the barium isotopes was inconsistent with the mix of odd to even barium isotopes derived from analysis of the Ba ii line at 4554 A in the spectrum of the metal-poor subgiant HD 140283. In this paper, we address Magain's challenge using new high resolution high signal-to-noise spectra of HD 140283, and nd, in contrast to his result, that a solar-like r-process isotopic mixture provides a fair t to the observed 4554 A pro le