Test of lepton flavor universality and search for lepton flavor violation in B -> Kll decays
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F21%3A10439861" target="_blank" >RIV/00216208:11320/21:10439861 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=oTKHycOqci" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=oTKHycOqci</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1007/JHEP03(2021)105" target="_blank" >10.1007/JHEP03(2021)105</a>
Alternative languages
Result language
angličtina
Original language name
Test of lepton flavor universality and search for lepton flavor violation in B -> Kll decays
Original language description
We present measurements of the branching fractions for the decays B -> K mu(+)mu(-) and B -> Ke(+)e(-), and their ratio (R-K), using a data sample of 711 fb(-1) that contains 772 x 10(6) B (B) over bar events. The data were collected at the Gamma(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The ratio RK is measured in five bins of dilepton invariant-mass-squared (q(2)): q(2) is an element of (0.1, 4.0), (4.00, 8.12), (1.0, 6.0), (10.2, 12.8) and (> 14.18) GeV2/c(4), along with the whole q(2) region. The R-K value for q(2) is an element of (1.0, 6.0) GeV2/c(4) is 1.03(-0.24)(+0.28) +/- 0.01. The first and second uncertainties listed are statistical and systematic, respectively. All results for R-K are consistent with Standard Model predictions. We also measure CP-averaged isospin asymmetries in the same q(2) bins. The results are consistent with a null asymmetry, with the largest difference of 2.6 standard deviations occurring for the q(2) is an element of (1.0, 6.0) GeV2/c(4) bin in the mode with muon final states. The measured differential branching fractions, dB/dq(2), are consistent with theoretical predictions for charged B decays, while the corresponding values are below the expectations for neutral B decays. We have also searched for lepton-flavor-violating B -> K mu(+/-)e(-/+) decays and set 90% confidence-level upper limits on the branching fraction in the range of 10(-8) for B+ -> K+ mu(+/-)e(-/+), and B-0 -> K-0 mu(+/-) e(-/+) modes.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10300 - Physical sciences
Result continuities
Project
<a href="/en/project/LTT17020" target="_blank" >LTT17020: Study of Beyond Standard Model Physics with the International Experiment Belle II in Japan</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2021
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of High Energy Physics [online]
ISSN
1029-8479
e-ISSN
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Volume of the periodical
Neuveden
Issue of the periodical within the volume
3
Country of publishing house
DE - GERMANY
Number of pages
24
Pages from-to
105
UT code for WoS article
000628215300001
EID of the result in the Scopus database
2-s2.0-85102586238