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Title: Combined analysis of Belle and Belle II data to determine the CKM angle ϕ3 using B+ → D($$ {K}_S^0 $$h+h−)h+ decays
A bstract We present a measurement of the Cabibbo-Kobayashi-Maskawa unitarity triangle angle ϕ 3 (also known as γ ) using a model-independent Dalitz plot analysis of B + → D ( $$ {K}_S^0 $$ K S 0 h + h − ) h + , where D is either a D 0 or $$ \overline{D} $$ D ¯ 0 meson and h is either a π or K . This is the first measurement that simultaneously uses Belle and Belle II data, combining samples corresponding to integrated luminosities of 711 fb − 1 and 128 fb − 1 , respectively. All data were accumulated from energy-asymmetric e + e − collisions at a centre-of-mass energy corresponding to the mass of the Υ(4 S ) resonance. We measure ϕ 3 = (78 . 4 ± 11 . 4 ± 0 . 5 ± 1 . 0)°, where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is from the uncertainties on external measurements of the D -decay strong-phase parameters.
Authors:
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Award ID(s):
1913789
Publication Date:
NSF-PAR ID:
10345617
Journal Name:
Journal of High Energy Physics
Volume:
2022
Issue:
2
ISSN:
1029-8479
Sponsoring Org:
National Science Foundation
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