Download or read book First Observation of the Cabibbo-suppressed Decays Xi+(c) ---] Sigma+ Pi- Pi+ and Xi+(c) ---] Sigma- Pi+ Pi+ and Measurement of Their Branching Ratios written by and published by . This book was released on 2008 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors report the first observation of two Cabibbo-suppressed decay modes,?{sub c} →?+?−?+ and?{sub c}+ →?−?+?+. They observe 56 ± 13 over a background of 21, and 23 ± 7 over a background of 12 events, respectively, for the signals. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c?− beam. The branching ratios of the decays relative to the Cabibbo-favored?{sub c}+ →?−?+?+ are measured to be B(?{sub c}+ →?+?−?+)/B(?{sub c}+ →?−?+?+) = 0.50 ± 0.20, and B(?{sub c}+ →?−?+?+)/B(?{sub c}+ →?−?+?+) = 0.23 ± 0.11, respectively. They also report branching ratios for the same decay modes of the?{sub c}+ relative to?{sub c}+ → pK−?+.