Searches for Λ[0 over b] and Ξ[0 over b] decays to K[0 over s]pπ[superscript -] and K[0 over s]pK[superscript -] final states with first observation of the Λ[0 over b] → K[0 over s]pπ[superscript -] decay
Name
Aaij-2014-Searches for and dec.pdf
Size
795.64 KB
Format
Adobe PDF
Checksum (MD5)
5fe267c551b9046fe61885972b66dac8
Author(s)
Williams, Michael
Ilten, Philip J
Date Issued
April 2014
Journal
Journal of High Energy Physics
Publisher
Springer-Verlag
Citation
Aaij, R., B. Adeva, M. Adinolfi, A. Affolder, Z. Ajaltouni, J. Albrecht, F. Alessio, et al. “Searches for Λ[0 over b] and Ξ[0 over b] decays to K[0 over s]pπ[superscript -] and K[0 over s]pK[superscript -] final states with first observation of the Λ[0 over b] → K[0 over s]pπ[superscript -] decay.” J. High Energ. Phys. 2014, no. 4 (April 2014). © CERN, for the benefit of the LHCb Collaboration
Version
Final published version
Abstract
A search for previously unobserved decays of beauty baryons to the final states K[0 over s]pπ[superscript -] and K[0 over s]pK[superscript -] is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 fb[superscript −1] of pp collisions. The Λ[0 over b] → [bar over K][superscript 0]pπ[superscript -] decay is observed with a significance of 8.6 σ, with branching fraction B(Λ[0 over b] → [bar over K][superscript 0]pπ[superscript -] = (1.26 ± 0.19 ± 0.09 ± 0.34 ± 0.05) × 10 [superscript -5], where the uncertainties are statistical, systematic, from the ratio of fragmentation fractions f [superscript Λ[0 over b]]/f[superscript d] and from the branching fraction of the B[superscript 0] → K[superscript 0]π[superscript +]π[superscript −] normalisation channel, respectively. A first measurement is made of the CP asymmetry, giving A[subscript CP](Λ[0 over b] → [bar over K][superscript 0]pπ[superscript -]) = 0.22 ± 0.13 (stat.) ± 0.03 (syst.). No significant signals are seen for Λ[0 over b] → K[0 over s]pK[superscript -] decays, Ξ[0 over b] decays to both the K[0 over s]pπ[superscript -] and K[0 over s]pK[superscript -] final states, and the Λ[0 over b] → D[bar over s] (→ K[0 over s]K[superscript -])p decay, and upper limits on their branching fractions are reported.
MIT Department
Massachusetts Institute of Technology. Department of Physics
Massachusetts Institute of Technology. Laboratory for Nuclear Science
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1007/jhep04(2014)087
