Measurement of CP asymmetry in Bs0 → Ds∓ K± decays

LHCb Collaboration; Marco Adinolfi; Jake Amey; Jozie Cottee Meldrum; Zahra Ghorbanimoghaddam; R. Lane; Alex M Marshall; Camille A Normand; Konstantinos A.  Petridis; Jonas H Rademacker; Jake Reich; Anatoly Solomin; Jaap J Velthuis; Rui Wang; Benedict D C Westhenry; Zak Williams; et al

doi:10.1007/JHEP03(2025)139

Measurement of CP asymmetry in B_s⁰ → D_s^∓ K^± decays

LHCb Collaboration, Marco Adinolfi, Jake Amey, Jozie Cottee Meldrum, Zahra Ghorbanimoghaddam, R. Lane, Alex M Marshall, Camille A Normand, Konstantinos A. Petridis, Jonas H Rademacker, Jake Reich, Anatoly Solomin, Jaap J Velthuis, Rui Wang, Benedict D C Westhenry, Zak Williams, et al

Research output: Contribution to journal › Article (Academic Journal) › peer-review

Abstract

A measurement of the CP-violating parameters in B_s⁰ → D_s^∓ K± decays is reported, based on the analysis of proton-proton collision data collected by the LHCb experiment corresponding to an integrated luminosity of 6 fb−1 at a centre-of-mass energy of 13 TeV. The measured parameters are obtained with a decay-time dependent analysis yielding Cf = 0.791 ± 0.061 ± 0.022,
A _f^ΔΓ= −0.051 ± 0.134 ± 0.058, A -_f^ΔΓ= −0.303 ± 0.125 ± 0.055, Sf = −0.571 ± 0.084 ± 0.023 and S-_f= −0.503 ± 0.084 ± 0.025, where the first uncertainty is statistical and the second systematic. This corresponds to CP violation in the interference between mixing and decay of about 8.6 σ. Together with the value of the B_s⁰mixing phase −2βs, these parameters are used to obtain a measurement of the CKM angle γ equal to (74 ± 12)° modulo 180°, where the uncertainty contains both statistical and systematic contributions. This result is combined with the previous LHCb measurement in this channel using 3 fb−1 resulting in a determination of γ = (81_-11⁺¹²)°.
.

Original language	English
Article number	139
Number of pages	33
Journal	Journal of High Energy Physics
Volume	2025
Issue number	3
DOIs	https://doi.org/10.1007/JHEP03(2025)139
Publication status	Published - 19 Mar 2025

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LHCb Collaboration, Adinolfi, M., Amey, J., Cottee Meldrum, J., Ghorbanimoghaddam, Z., Lane, R., Marshall, A. M., Normand, C. A., Petridis, K. A., Rademacker, J. H., Reich, J., Solomin, A., Velthuis, J. J., Wang, R., Westhenry, B. D. C., Williams, Z., & et al (2025). Measurement of CP asymmetry in B_s⁰ → D_s^∓ K^± decays. Journal of High Energy Physics, 2025(3), Article 139. https://doi.org/10.1007/JHEP03(2025)139

@article{2a474da11be74e50887a25449f21e1b2,

title = "Measurement of CP asymmetry in Bs0 → Ds∓ K± decays",

abstract = "A measurement of the CP-violating parameters in Bs0 → Ds∓ K± decays is reported, based on the analysis of proton-proton collision data collected by the LHCb experiment corresponding to an integrated luminosity of 6 fb−1 at a centre-of-mass energy of 13 TeV. The measured parameters are obtained with a decay-time dependent analysis yielding Cf = 0.791 ± 0.061 ± 0.022, A f ΔΓ = −0.051 ± 0.134 ± 0.058, A -f ΔΓ = −0.303 ± 0.125 ± 0.055, Sf = −0.571 ± 0.084 ± 0.023 and S-f = −0.503 ± 0.084 ± 0.025, where the first uncertainty is statistical and the second systematic. This corresponds to CP violation in the interference between mixing and decay of about 8.6 σ. Together with the value of the Bs0 mixing phase −2βs, these parameters are used to obtain a measurement of the CKM angle γ equal to (74 ± 12)° modulo 180°, where the uncertainty contains both statistical and systematic contributions. This result is combined with the previous LHCb measurement in this channel using 3 fb−1 resulting in a determination of γ = (81-11+12)°..",

author = "{LHCb Collaboration} and Marco Adinolfi and Jake Amey and {Cottee Meldrum}, Jozie and Zahra Ghorbanimoghaddam and R. Lane and Marshall, {Alex M} and Normand, {Camille A} and Petridis, {Konstantinos A.} and Rademacker, {Jonas H} and Jake Reich and Anatoly Solomin and Velthuis, {Jaap J} and Rui Wang and Westhenry, {Benedict D C} and Zak Williams and {et al}",

note = "Publisher Copyright: {\textcopyright} The Author(s) 2025.",

year = "2025",

month = mar,

day = "19",

doi = "10.1007/JHEP03(2025)139",

language = "English",

volume = "2025",

journal = "Journal of High Energy Physics",

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LHCb Collaboration, Adinolfi, M , Amey, J , Cottee Meldrum, J , Ghorbanimoghaddam, Z, Lane, R, Marshall, AM , Normand, CA , Petridis, KA , Rademacker, JH , Reich, J , Solomin, A , Velthuis, JJ, Wang, R, Westhenry, BDC , Williams, Z & et al 2025, 'Measurement of CP asymmetry in B_s⁰ → D_s^∓ K^± decays', Journal of High Energy Physics, vol. 2025, no. 3, 139. https://doi.org/10.1007/JHEP03(2025)139

TY - JOUR

T1 - Measurement of CP asymmetry in Bs0 → Ds∓ K± decays

AU - LHCb Collaboration

AU - Adinolfi, Marco

AU - Amey, Jake

AU - Cottee Meldrum, Jozie

AU - Ghorbanimoghaddam, Zahra

AU - Lane, R.

AU - Marshall, Alex M

AU - Normand, Camille A

AU - Petridis, Konstantinos A.

AU - Rademacker, Jonas H

AU - Reich, Jake

AU - Solomin, Anatoly

AU - Velthuis, Jaap J

AU - Wang, Rui

AU - Westhenry, Benedict D C

AU - Williams, Zak

AU - et al,

PY - 2025/3/19

Y1 - 2025/3/19

N2 - A measurement of the CP-violating parameters in Bs0 → Ds∓ K± decays is reported, based on the analysis of proton-proton collision data collected by the LHCb experiment corresponding to an integrated luminosity of 6 fb−1 at a centre-of-mass energy of 13 TeV. The measured parameters are obtained with a decay-time dependent analysis yielding Cf = 0.791 ± 0.061 ± 0.022, A f ΔΓ = −0.051 ± 0.134 ± 0.058, A -f ΔΓ = −0.303 ± 0.125 ± 0.055, Sf = −0.571 ± 0.084 ± 0.023 and S-f = −0.503 ± 0.084 ± 0.025, where the first uncertainty is statistical and the second systematic. This corresponds to CP violation in the interference between mixing and decay of about 8.6 σ. Together with the value of the Bs0 mixing phase −2βs, these parameters are used to obtain a measurement of the CKM angle γ equal to (74 ± 12)° modulo 180°, where the uncertainty contains both statistical and systematic contributions. This result is combined with the previous LHCb measurement in this channel using 3 fb−1 resulting in a determination of γ = (81-11+12)°..

AB - A measurement of the CP-violating parameters in Bs0 → Ds∓ K± decays is reported, based on the analysis of proton-proton collision data collected by the LHCb experiment corresponding to an integrated luminosity of 6 fb−1 at a centre-of-mass energy of 13 TeV. The measured parameters are obtained with a decay-time dependent analysis yielding Cf = 0.791 ± 0.061 ± 0.022, A f ΔΓ = −0.051 ± 0.134 ± 0.058, A -f ΔΓ = −0.303 ± 0.125 ± 0.055, Sf = −0.571 ± 0.084 ± 0.023 and S-f = −0.503 ± 0.084 ± 0.025, where the first uncertainty is statistical and the second systematic. This corresponds to CP violation in the interference between mixing and decay of about 8.6 σ. Together with the value of the Bs0 mixing phase −2βs, these parameters are used to obtain a measurement of the CKM angle γ equal to (74 ± 12)° modulo 180°, where the uncertainty contains both statistical and systematic contributions. This result is combined with the previous LHCb measurement in this channel using 3 fb−1 resulting in a determination of γ = (81-11+12)°..

U2 - 10.1007/JHEP03(2025)139

DO - 10.1007/JHEP03(2025)139

M3 - Article (Academic Journal)

SN - 1029-8479

VL - 2025

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

IS - 3

M1 - 139

ER -