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Author 
BABAR and Belle Collaborations (Adachi, I.. et al); MartinezVidal, F.; Oyanguren, A. 


Title 
First Evidence for cos 2 beta > 0 and Resolution of the CabibboKobayashiMaskawa QuarkMixing Unitarity Triangle Ambiguity 
Type 
Journal Article 

Year 
2018 
Publication 
Physical Review Letters 
Abbreviated Journal 
Phys. Rev. Lett. 


Volume 
121 
Issue 
26 
Pages 
261801  11pp 


Keywords 



Abstract 
We present first evidence that the cosine of the CPviolating weak phase 2 beta is positive, and hence exclude trigonometric multifold solutions of the CabibboKobayashiMaskawa (CKM) Unitarity Triangle using a timedependent Dalitz plot analysis of B0 > D(*) h(0) with D > KS(0)pi(+)pi() decays, where h(0) is an element of {pi(0), eta, omega} denotes a light unflavored and neutral hadron. The measurement is performed combining the final data sets of the BABAR and Belle experiments collected at the (sic)(4S) resonance at the asymmetricenergy B factories PEPII at SLAC and KEKB at KEK, respectively. The data samples contain (471 +/ 3) x 10(6) B (B) over bar pairs recorded by the BABAR detector and (772 +/ 11) x 10(6) B (B) over bar pairs recorded by the Belle detector. The results of the measurement are sin 2 beta = 0.80 +/ 0.14 (stat) +/ 0.06 (syst) +/ 0.03 (model) and cos 2 beta = 0.91 +/ 0.22(stat) +/ 0.09 (syst) +/ 0.07(model). The result for the direct measurement of the angle beta of the CKM Unitarity Triangle is beta = [22.5 +/ 4.4 (stat) +/ 1.2 (syst) +/ 0.6(model)]degrees. The measurement assumes no direct CP violation in B0 > D(*) h(0) decays. The quoted model uncertainties are due to the composition of the D0 > KS(0)pi(+)pi() decay amplitude model, which is newly established by performing a Dalitz plot amplitude analysis using a highstatistics e(+)e() > c (c) over bar data sample. CP violation is observed in B0 > D(*) h(0) decays at the level of 5.1 standard deviations. The significance for cos 2 beta > 0 is 3.7 standard deviations. The trigonometric multifold solution pi/2 – beta = (68.1 +/ 0.7)degrees is excluded at the level of 7.3 standard deviations. The measurement resolves an ambiguity in the determination of the apex of the CKM Unitarity Triangle. 


Address 
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS IN2P3, LAPP, F74941 Annecy Le Vieux, France 


Corporate Author 

Thesis 



Publisher 
Amer Physical Soc 
Place of Publication 

Editor 



Language 
English 
Summary Language 

Original Title 



Series Editor 

Series Title 

Abbreviated Series Title 



Series Volume 

Series Issue 

Edition 



ISSN 
00319007 
ISBN 

Medium 



Area 

Expedition 

Conference 



Notes 
WOS:000454432900004 
Approved 
no 


Is ISI 
yes 
International Collaboration 
yes 


Call Number 
IFIC @ pastor @ 
Serial 
3858 

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