[SLAC] [SLAC Pubs and Reports] SLAC-PUB-7713Bounding the effect of penguin diagrams in alphaCP(B0 --> pi+pi-) Abstract A clean determination of the angle $\alpha$ of the unitary triangle from $B\to \pi\pi$ decays requires an isospin analysis. If the $B \to \pi^0\pi^0$ and $\bar B \to \pi^0\pi^0$ decay rates are small it may be hard to carry out this analysis. Here we show that an upper bound on the error on $\sin 2\alpha$ due to penguin diagram effects can be obtained using only the measured rate $\BR(B^\pm \to \pi^\pm \pi^0)$ and an upper bound on the combined rate $\BR(B \to \pi^0 \pi^0) + \BR(\bar B \to \pi^0 \pi^0)$. Since no $b$ flavor tagging is needed to measure this combined rate, the bound that can be achieved may be significantly better than any approach which requires separate flavor-tagged neutral pion information. (Equations render on Windows, Mac OS, AIX, Linux, Solaris, and IRIX with the techexplorer plug-in.) Full Text PDF slac-pub-7713 (547 KB) Compressed PostScript Not available for this document. techexplorer slac-pub-7713 (3.79 KB) More Information Full bibliographic data for this document, including its complete author list, is (or soon will be) available from SLAC's SPIRES-HEP Database. Please report problems with this file to posting@slac.stanford.edu. The SLAC preprint inventory is provided by the SLAC Technical Publications Department. Page generated 04 Apr 2001 @ 15:10 PDT by htmlme.pl
A clean determination of the angle $\alpha$ of the unitary triangle from $B\to \pi\pi$ decays requires an isospin analysis. If the $B \to \pi^0\pi^0$ and $\bar B \to \pi^0\pi^0$ decay rates are small it may be hard to carry out this analysis. Here we show that an upper bound on the error on $\sin 2\alpha$ due to penguin diagram effects can be obtained using only the measured rate $\BR(B^\pm \to \pi^\pm \pi^0)$ and an upper bound on the combined rate $\BR(B \to \pi^0 \pi^0) + \BR(\bar B \to \pi^0 \pi^0)$. Since no $b$ flavor tagging is needed to measure this combined rate, the bound that can be achieved may be significantly better than any approach which requires separate flavor-tagged neutral pion information. (Equations render on Windows, Mac OS, AIX, Linux, Solaris, and IRIX with the techexplorer plug-in.)
(Equations render on Windows, Mac OS, AIX, Linux, Solaris, and IRIX with the techexplorer plug-in.)
PDF slac-pub-7713 (547 KB) Compressed PostScript Not available for this document. techexplorer slac-pub-7713 (3.79 KB)
Not available for this document.
Full bibliographic data for this document, including its complete author list, is (or soon will be) available from SLAC's SPIRES-HEP Database.