Search for $CP$ violation in $D_{(s)}^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$ decays using triple and quadruple products

Abstract

We perform the first search for $CP$ violation in $D_{(s)}^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$ decays. We use a combined data set from the Belle and Belle II experiments, which study $e^{+}{e}^{-}$ collisions at center-of-mass energies at or near the ${\rm Y}(4S)$ resonance. We use 980 fb${}^{-1}$ of data from Belle and 428 fb${}^{-1}$ of data from Belle~II. We measure six $CP$-violating asymmetries that are based on triple products and quadruple products of the momenta of final-state particles, and also the particles' helicity angles. We obtain a precision at the level of 0.5% for $D^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$ decays, and better than 0.3% for $D_s^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$ decays. No evidence of $CP$ violation is found. Our results for the triple-product asymmetries are the most precise to date for singly-Cabibbo-suppressed $D^{+}$ decays. Our results for the other asymmetries are the first such measurements performed for charm decays.

21 pages, 10 figures

References in corpus (8)

• PYTHIA 6.4 Physics and Manual
• An Introduction to PYTHIA 8.2
• Charm CPV: observation and prospects
• Final-state interactions in the CP asymmetries of charm-meson two-body decays
• A $U$-Spin Anomaly in Charm CP Violation
• Enhanced charm CP asymmetries from final state interactions
• CP violation in multibody decays of beauty baryons
• Searching for $CP$ violation through two-dimensional angular distributions in four-body decays of bottom and charmed baryons