Strong Isospin Mixing Effects on the Extraction of $\Delta I=3/2$ Non-Leptonic Hyperon Decay Amplitudes

Abstract

The existence of isospin admixtures in the physical $\Lambda$, ${\pi }^o$ complicates the extraction of Delta I=3/2 non-leptonic hyperon decay amplitudes from experimental data, allowing contributions associated with large Delta I=1/2 amplitudes to appear in the (nominally) Delta I=3/2 amplitudes obtained ignoring these admixtures. We show how to correct for this effect to leading order in $(m_d-m_u)$ and extract the true Delta I=3/2 amplitudes. The resulting corrections are modest ($<25\%$) for s-waves, but extremely large, $\simeq 100\%$ and $\simeq 400\%$ for $\Lambda$ and $\Xi$ p-waves, respectively.

Comments: 15 pages, Plain TEX Entire manuscript available as a ps file at http://www.physics.adelaide.edu.au/theory/home.html Also available via anonymous ftp at ftp://adelphi.adelaide.edu.au/pub/theory/ADP-95-4.T171.ps To appear in Physics Letters B