First observation of the Cabibbo-suppressed decays Xi(+)(c)->Sigma(+)pi(-)pi(+) and Xi(+)(c)->Sigma(-)pi(+)pi(+) and measurement of their branching ratios

Vazquez-Jauregui E., Engelfried J., Akgun U., Alkhazov G., Amaro-Reyes J., Atamantchouk A. G., ...More

PHYSICS LETTERS B, vol.666, no.4, pp.299-304, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 666 Issue: 4
  • Publication Date: 2008
  • Doi Number: 10.1016/j.physletb.2008.07.072
  • Journal Name: PHYSICS LETTERS B
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.299-304
  • Istanbul University Affiliated: No


We report the first observation of two Cabibbo-suppressed ecay modes, Xi(+)(c) -> Sigma(+)pi(-)pi(+) and Xi c+ -> Sigma(-)pi(+)pi(+). We observe 59 +/- 14 over a background of 87, and 22 +/- 8 over a background of 13 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 Sigma(-) beam. The branching ratios of the decays relative to the Cabibbo-favored Xi c+ -> Xi(-)pi(+)pi(+) are measured to be B(Xi(+)(c) -> Sigma(+)pi(-)pi(+))/B(Xi(+)(c) -> Xi(-)pi(+)pi(+)) = 0.48 +/- 0.20, and B(Xi(+)(c) -> Sigma(-)pi(+)pi(+))/B(Xi(+)(c) -> Sigma(-)pi(+)pi(+)) = 0.18 +/- 0.09, respectively. We also report branching ratios for the same decay modes of the Delta(+)(c) relative to Delta(+)(c) -> pK(-)pi(+.) (C) 2008 Elsevier B.V. All rights reserved.