{"id":36549,"date":"2026-06-08T13:16:40","date_gmt":"2026-06-08T13:16:40","guid":{"rendered":"https:\/\/lamarr-institute.org\/publication\/precision-measurement-of-cp-violation-and-branching-fractions-in-bpm-to-k0_mathrms-hpm-h-pi-k-decays-and-search-for-the-rare-decay-b_cpm-to-k0_mathrms-kp\/"},"modified":"2026-06-08T13:16:40","modified_gmt":"2026-06-08T13:16:40","slug":"precision-measurement-of-cp-violation-and-branching-fractions-in-bpm-to-k0_mathrms-hpm-h-pi-k-decays-and-search-for-the-rare-decay-b_cpm-to-k0_mathrms-kp","status":"publish","type":"publication","link":"https:\/\/lamarr-institute.org\/de\/publication\/precision-measurement-of-cp-violation-and-branching-fractions-in-bpm-to-k0_mathrms-hpm-h-pi-k-decays-and-search-for-the-rare-decay-b_cpm-to-k0_mathrms-kp\/","title":{"rendered":"Precision measurement of CP violation and branching fractions in $B^{\\pm} \\to K^0_{\\mathrm{S}} h^{\\pm} (h = \\pi, K)$ decays and search for the rare decay $B_c^{\\pm} \\to K^0_{\\mathrm{S}} K^{\\pm}$"},"content":{"rendered":"<p>The decay $B^{\\pm} \\to K^0_{\\mathrm{S}} \\pi^{\\pm}$, with a CP asymmetry expected to be close to zero in the Standard Model, is theoretically clean and sensitive to potential new physics. An analysis of the decays $B^{\\pm} \\to K^0_{\\mathrm{S}} \\pi^{\\pm}$ and $B^{\\pm} \\to K^0_{\\mathrm{S}} K^{\\pm}$ is performed using proton-proton collision data collected by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 $\\mathrm{fb}^{-1}$. The CP asymmetries are determined to be ${\\cal A}^{CP}(B^{\\pm} \\to K^0_{\\mathrm{S}} \\pi^{\\pm})=-0.028\\pm 0.009\\pm 0.009$ and ${\\cal A}^{CP}(B^{\\pm} \\to K^0_{\\mathrm{S}} K^{\\pm})=0.118\\pm 0.062 \\pm 0.031$, and the branching fraction ratio is measured to be ${\\cal B}(B^{\\pm} \\to K^0_{\\mathrm{S}} K^{\\pm})\/{\\cal B}(B^{\\pm} \\to K^0_{\\mathrm{S}} \\pi^{\\pm})=0.055\\pm 0.004 \\pm 0.002$, where the first uncertainties are statistical and the second are systematic. These results are the most precise measurements of these quantities to date. A search for the rare decay $B_c^{\\pm} \\to K^0_{\\mathrm{S}} K^{\\pm}$ is also performed. No significant signal is observed, and the upper limit on the product of the branching fraction ratio ${\\cal B}(B_c^{\\pm} \\to K^0_{\\mathrm{S}} K^{\\pm})\/{\\cal B}(B^{\\pm} \\to K^0_{\\mathrm{S}} \\pi^{\\pm})$ and the fragmentation-fraction ratio $f_c\/f_u$ is set to be 0.015 (0.016) at the 90\\% (95\\%) confidence level.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The decay $B^{\\pm} \\to K^0_{\\mathrm{S}} \\pi^{\\pm}$, with a CP asymmetry expected to be close to zero in the Standard Model, is theoretically clean and sensitive to potential new physics. An analysis of the decays $B^{\\pm} \\to K^0_{\\mathrm{S}} \\pi^{\\pm}$ and $B^{\\pm} \\to K^0_{\\mathrm{S}} K^{\\pm}$ is performed using proton-proton collision data collected by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 $\\mathrm{fb}^{-1}$. The [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"template":"","meta":{"_acf_changed":false,"footnotes":""},"publication-type":[30],"class_list":["post-36549","publication","type-publication","status-publish","hentry","publication-type-article"],"acf":[],"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication\/36549","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication"}],"about":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/types\/publication"}],"author":[{"embeddable":true,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/users\/12"}],"version-history":[{"count":0,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication\/36549\/revisions"}],"wp:attachment":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/media?parent=36549"}],"wp:term":[{"taxonomy":"publication-type","embeddable":true,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication-type?post=36549"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}