The flavour of New Physics in the loops of hadronic beauty decays
Lead Research Organisation:
University of Warwick
Department Name: Physics
Abstract
The Standard Model (SM) of Particle Physics, whilst incredibly successfully, is known not to provide an
adequate description for various observed physical phenomena. Precision measurements in the flavour
sector are an ideal laboratory to search for New Physics (NP) beyond the SM at very high energy scales.
This proposal will make precise measurements of highly NP sensitive decay rate ratios and weak phases,
which arise in beauty-quark to strange- or down-quark transitions, using data collected at the Large
Hadron Collider beauty (LHCb) experiment.
The weak phase under consideration, called phi-s, has a very small and precisely known value in the SM
making its determination a prime avenue for exploration of NP. However, interpretation of the experimental
measurement, within the framework of the SM, is complicated by unknown polluting contributions. This
issue is overcome in this proposal using a novel analysis technique, which simultaneously extracts the
unknown contribution by exploiting flavour symmetries that are known to hold for the decays under study.
This proposal will make the world's first precision measurement of phi-s using this analysis method.
A family of seven inter-related decay modes of neutral B-mesons to hadrons, via vector-vector states, will
be investigated. Beyond extraction of the weak phase, phi-s, understanding of the complex amplitude
structure of these decays will provide insights into the role of New Physics in their decay dynamics. This
proposal will make world's first and world's most precise measurements of various compelling decay rate
parameters and phases which probe the fundamental nature of these processes.
During the timeline of this proposal the available datasets will increase by a factor of forty and the
project will deliver cutting-edge developments in analysis techniques and software tools. The outcome is
a step-change in the physics reach, which will permit these precision measurements to be made for the
first time.
adequate description for various observed physical phenomena. Precision measurements in the flavour
sector are an ideal laboratory to search for New Physics (NP) beyond the SM at very high energy scales.
This proposal will make precise measurements of highly NP sensitive decay rate ratios and weak phases,
which arise in beauty-quark to strange- or down-quark transitions, using data collected at the Large
Hadron Collider beauty (LHCb) experiment.
The weak phase under consideration, called phi-s, has a very small and precisely known value in the SM
making its determination a prime avenue for exploration of NP. However, interpretation of the experimental
measurement, within the framework of the SM, is complicated by unknown polluting contributions. This
issue is overcome in this proposal using a novel analysis technique, which simultaneously extracts the
unknown contribution by exploiting flavour symmetries that are known to hold for the decays under study.
This proposal will make the world's first precision measurement of phi-s using this analysis method.
A family of seven inter-related decay modes of neutral B-mesons to hadrons, via vector-vector states, will
be investigated. Beyond extraction of the weak phase, phi-s, understanding of the complex amplitude
structure of these decays will provide insights into the role of New Physics in their decay dynamics. This
proposal will make world's first and world's most precise measurements of various compelling decay rate
parameters and phases which probe the fundamental nature of these processes.
During the timeline of this proposal the available datasets will increase by a factor of forty and the
project will deliver cutting-edge developments in analysis techniques and software tools. The outcome is
a step-change in the physics reach, which will permit these precision measurements to be made for the
first time.
Publications
Aaij R
(2024)
Improved Measurement of C P Violation Parameters in B s 0 ? J / ? K + K - Decays in the Vicinity of the ? ( 1020 ) Resonance
in Physical Review Letters
Amhis Y
(2023)
Averages of b -hadron, c -hadron, and t -lepton properties as of 2021
in Physical Review D
Dembinski H
(2022)
Custom Orthogonal Weight functions (COWs) for event classification
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Related Projects
| Project Reference | Relationship | Related To | Start | End | Award Value |
|---|---|---|---|---|---|
| EP/X014746/1 | 02/10/2022 | 23/04/2023 | £1,284,265 | ||
| EP/X014746/2 | Transfer | EP/X014746/1 | 31/05/2023 | 30/04/2028 | £1,260,011 |
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| Exploitation Route | The analysis methods have a multitude of uses in other heavy flavour experiments, for example future upgrades of LHCb, the Belle-II experiment and the Future Circular Collider running in ee mode at the Z threshold. |
| Sectors | Other |
| URL | https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/Summary_all.html |
| Description | Getting a flavour for New Physics with precision measurements of tree-level beauty decays |
| Amount | £418,850 (GBP) |
| Funding ID | ST/R004536/2 |
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| End | 09/2024 |
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| Amount | £2,268,145 (GBP) |
| Funding ID | ST/S000909/1 |
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| Sector | Public |
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| Start | 09/2019 |
| End | 12/2022 |
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| Sector | Academic/University |
| PI Contribution | Made us of FCC-ee simulation and centralised data production to perform studies of the physics reach and detector design. |
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| Department | CERN LHC LHCb |
| Country | Switzerland |
| Sector | Public |
| PI Contribution | I have been working on analysis of LHCb data and contributing to performance tasks for the experiment. I have acted as an internal reviewer on several occasions for the collaboration. I currently hold a management position within the collaboration. |
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| Organisation | Particle Data Group |
| Country | United States |
| Sector | Academic/University |
| PI Contribution | I provide the numbers for the world averages of CKM angles (alpha, beta and gamma). I have written the review on "Determination of CKM angles from B hadrons" |
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| Open Source License? | Yes |
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| Type Of Technology | Software |
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| Open Source License? | Yes |
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