S-waves and the measurement ofCPviolating phases inBsdecays

2008/12/31 by Sheldon Stone, S. Stone, L. Zhang +1 · 5 citations
Chemistry · Physics and Astronomy · #Analytical Chemistry (journal) #Bar (unit) #CP violation #Chemistry #Meson #Mixing (physics) #Neutrino Physics Research #Order (exchange) #Particle physics #Particle physics theoretical and experimental studies #Phase (matter) #Physics #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #hep-ex #hep-ph

paper · pdf · doi:10.1103/physrevd.79.074024

published as Phys.Rev.D79:074024,2009 · To be published in Physical Review D; 7 pages, 5 figures, v2-3 fixed typo's; response to reviewers

arxiv created 2009/04/01 · openalex publication_date 2009/04/29 · arxiv updated 2014/11/18 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

Heavy, as yet undiscovered particles, can affect measurements of CP violation in the B system. Measuring CP violation in the B_s system provides an excellent place to observe such effects since standard model sources are predicted to produce very small effects. The angle \ensuremath-2\ensuremathβ_s, the ``phase of B_s\ensuremath-B_s mixing,'' thought to be best measured in B_s\ensuremath→J/\ensuremathψ\ensuremathφ decays is of order \ensuremath-0.04, while the CP violating asymmetry in B_s\ensuremath→\ensuremathφ\ensuremathφ is predicted to be zero, due to the cancellation of the mixing phase with the decay phase. Recent measurements of \ensuremathβ_s in J/\ensuremathψ\ensuremathφ, while not definitive, are much larger than the standard model predictions. Measurements in the B⁰ and D_s⁺ systems of analogous modes point toward a 5--10% contamination of S-wave K⁺K^\ensuremath- under the \ensuremathφ peak. This S-wave was not taken into account in these recent analyses. Furthermore this S-wave can also materialize as a f₀(980) meson that decays to \ensuremathπ⁺\ensuremathπ^\ensuremath-, making the final state J/\ensuremathψf₀ useful for measuring \ensuremathβ_s with the added advantage of not requiring an angular analysis. Rate estimates, while not precise, predict four to five times fewer such events than those in the J/\ensuremathψ\ensuremathφ mode. The error on \ensuremathβ_s, however, may be similar. We also remark on S-wave problems with the B_s\ensuremath→\ensuremathφ\ensuremathφ mode, and possible systematic checks using B_s\ensuremath→\ensuremathφf₀.

Citations

• CP violation and the CKM matrix: assessing the impact of the asymmetric B factories

Cited by

• Measurement of theCP-violating phaseβsJ/ψϕinBs0→J/ψϕdecays with the CDF II detector
• Dalitz plot analysis ofDs+→K+K−π+
• Measurement of the CP-violating phase φ _s in B_s⁰ → J/ψ φ decays in ATLAS at 13 TeV
• Measurement of the CP -violating phaseϕsinB¯s0→J/ψπ+π−decays
• Time-dependent Dalitz-plot formalism for Bq0→J/ψh+h−

Related

• CP Violation in the B_s⁰ system
• Determination of the Sign of the Decay Width Difference in theBs0System
• Determination of 2βsin Bs0→ J/ψK+K−decays in the presence of a K+K−S-wave contribution
• Measurement of theCP-violating phaseβsJ/ψϕinBs0→J/ψϕdecays with the CDF II detector
• Measurements of CP violation in B mixing through B → J/ψX decays at LHCb