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Title: Constraining electroweak penguin graph contributions in measurements of the CKM phase alpha using B π π and B ρ ρ decays

Abstract

The unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix has been well established by both direct and indirect measurements without any evidence of discrepancy. The CKM weak phase α is directly measured using an isospin analysis in $$\textit{B → ππ}$$ and $$\textit{B → ρρ}$$ assuming that electroweak penguin contributions are ignorable. However, electroweak penguins are sensitive to NP, hence, it is important to experimentally estimate their effects. We determine the size of both electroweak penguin and isospin amplitudes, directly from $$\textit{B → ππ}$$ and $$\textit{B → ρρ}$$ experimental data, using in addition the indirectly measured value of α. We find that electroweak penguin contribution are indeed small and agree with SM expectations within 1σ. We also find that there is a mild enhancement of the $$ΔI = \frac{1}{2}$$ transition amplitude.

Authors:
ORCiD logo; ORCiD logo; ORCiD logo; ORCiD logo
Publication Date:
Research Org.:
Univ. of California, San Diego, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC); Science and Engineering Research Board (SERB); Innovation, Science and Economic Development Canada (ISED); Ministry of Research, Innovation and Science
OSTI Identifier:
1632921
Alternate Identifier(s):
OSTI ID: 1801926
Grant/Contract Number:  
de-sc0009919; SC0009919; SERB/PHY/F181/2018-19/G210
Resource Type:
Published Article
Journal Name:
Physical Review D
Additional Journal Information:
Journal Name: Physical Review D Journal Volume: 101 Journal Issue: 7; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; Astronomy & Astrophysics; Physics

Citation Formats

Nayak, Abinash Kumar, Sinha, Rahul, Karan, Anirban, and Grinstein, Benjamin. Constraining electroweak penguin graph contributions in measurements of the CKM phase alpha using B → π π and B → ρ ρ decays. United States: N. p., 2020. Web. doi:10.1103/PhysRevD.101.073001.
Nayak, Abinash Kumar, Sinha, Rahul, Karan, Anirban, & Grinstein, Benjamin. Constraining electroweak penguin graph contributions in measurements of the CKM phase alpha using B → π π and B → ρ ρ decays. United States. https://doi.org/10.1103/PhysRevD.101.073001
Nayak, Abinash Kumar, Sinha, Rahul, Karan, Anirban, and Grinstein, Benjamin. Wed . "Constraining electroweak penguin graph contributions in measurements of the CKM phase alpha using B → π π and B → ρ ρ decays". United States. https://doi.org/10.1103/PhysRevD.101.073001.
@article{osti_1632921,
title = {Constraining electroweak penguin graph contributions in measurements of the CKM phase alpha using B → π π and B → ρ ρ decays},
author = {Nayak, Abinash Kumar and Sinha, Rahul and Karan, Anirban and Grinstein, Benjamin},
abstractNote = {The unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix has been well established by both direct and indirect measurements without any evidence of discrepancy. The CKM weak phase α is directly measured using an isospin analysis in $\textit{B → ππ}$ and $\textit{B → ρρ}$ assuming that electroweak penguin contributions are ignorable. However, electroweak penguins are sensitive to NP, hence, it is important to experimentally estimate their effects. We determine the size of both electroweak penguin and isospin amplitudes, directly from $\textit{B → ππ}$ and $\textit{B → ρρ}$ experimental data, using in addition the indirectly measured value of α. We find that electroweak penguin contribution are indeed small and agree with SM expectations within 1σ. We also find that there is a mild enhancement of the $ΔI = \frac{1}{2}$ transition amplitude.},
doi = {10.1103/PhysRevD.101.073001},
journal = {Physical Review D},
number = 7,
volume = 101,
place = {United States},
year = {2020},
month = {4}
}

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