Letter
Open Access

Precise $K^{*} (892) \to K π$ branching fractions

Vladimir V. Gligorov ¹ and Dean J. Robinson ^2,3

¹LPNHE, Sorbonne Université, Paris Diderot Sorbonne Paris Cité, CNRS/IN2P3, Paris, France
²Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA
³Berkeley Center for Theoretical Physics, Department of Physics, University of California, Berkeley, California 94720, USA

Phys. Rev. D 113, L011503 – Published 30 January, 2026

DOI: https://doi.org/10.1103/s87z-1978

Abstract

Although discovered more than sixty years ago, direct measurement of the $K^{*} (892) \to K π$ branching fractions is a formidable challenge that has not been attempted. Typically they are assumed to obey the isospin limit in hundreds of particle data measurements. We show that an abundance of recent amplitude analyses and other data, however, enables recovery of the ratios $B (K^{* +} \to K^{+} π^{0}) / B (K^{* +} \to K_{S}^{0} π^{+})$ and $4 B (K^{* 0} \to K_{S}^{0} π^{0}) / B (K^{* 0} \to K^{+} π^{-})$ at $\sim 5 %$ precision.

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References (45)

M. Alston, L. W. Alvarez, P. Eberhard, M. L. Good, W. Graziano, H. K. Ticho, and S. G. Wojcicki, Resonance in the $K π$ system, Phys. Rev. Lett. 6, 300 (1961).
S. Navas et al. (Particle Data Group), Review of particle physics, Phys. Rev. D 110, 030001 (2024).
M. Ablikim et al. (BESIII Collaboration), Study of $D^{+} \to K_{S}^{0} K^{*} (892)^{+}$ in $D^{+} \to K_{S}^{0} K_{S}^{0} π^{+}$ , Phys. Rev. D 110, 092006 (2024).
M. Ablikim et al. (BESIII Collaboration), Study of the semileptonic decay $D^{0} \to {\bar{K}}^{0} π^{-} e^{+} ν_{e}$ , J. High Energy Phys. 03 (2025) 197.
M. Ablikim et al. (BESIII Collaboration), Test of lepton universality and measurement of the form factors of $D^{0} \to K^{*} (892)^{-} μ^{+} ν_{μ}$ , Phys. Rev. Lett. 134, 011803 (2025).
M. Ablikim et al. (BESIII Collaboration), Analysis of the dynamics of the decay $D^{+} \to K_{S}^{0} π^{0} e^{+} ν_{e}$ , J. High Energy Phys. 10 (2024) 199.
M. Ablikim et al. (BESIII Collaboration), Amplitude analysis and branching fraction measurement of the Cabibbo-favored decay $D^{+} \to K^{-} π^{+} π^{+} π^{0}$ , arXiv:2412.11040.
B. Aubert et al. (BABAR Collaboration, Measurement of branching fractions and $C P$ and isospin asymmetries in $B \to K^{*} (892) γ$ decays, Phys. Rev. Lett. 103, 211802 (2009).
T. Horiguchi et al. (Belle Collaboration), Evidence for isospin violation and measurement of $C P$ asymmetries in $B \to K^{*} (892) γ$ , Phys. Rev. Lett. 119, 191802 (2017).
I. Adachi et al. (Belle-II Collaboration), Measurement of $B \to K^{*} (892) γ$ decays at Belle II, J. High Energy Phys. 09 (2025) 024.
M. Ablikim et al. (BESIII Collaboration), Measurement of absolute branching fractions of $D_{s}^{+}$ hadronic decays, J. High Energy Phys. 05 (2024) 335.
M. Ablikim et al. (BESIII Collaboration), Study of the decay $D^{+} \to K^{*} (892)^{+} K_{S}^{0}$ in $D^{+} \to K^{+} K_{S}^{0} π^{0}$ , Phys. Rev. D 104, 012006 (2021).
M. Ablikim et al. (BESIII Collaboration), Measurements of the absolute branching fractions and $C P$ asymmetries for $D^{+} \to K_{S, L}^{0} K^{+} (π^{0})$ , Phys. Rev. D 99, 032002 (2019).
T. E. Coan et al. (CLEO Collaboration), Absolute branching fraction measurements of exclusive $D^{0}$ semileptonic decays, Phys. Rev. Lett. 95, 181802 (2005).
J. M. Link et al. (FOCUS Collaboration), Analysis of the semileptonic decay $D^{0} \to {\bar{K}}^{0} π^{-} μ^{+} ν$ , Phys. Lett. B 607, 67 (2005).
S. Kopp et al. (CLEO Collaboration), Dalitz analysis of the decay $D^{0} \to K^{-} π^{+} π^{0}$ , Phys. Rev. D 63, 092001 (2001).
H. Muramatsu et al. (CLEO Collaboration), Dalitz analysis of $D^{0} \to K_{S}^{0} π^{+} π^{-}$ , Phys. Rev. Lett. 89, 251802 (2002); 90, 059901(E) (2003).
B. Aubert et al. (BABAR Collaboration, Improved measurement of the CKM angle $γ$ in $B^{\mp} \to D^{(*)} K^{(* \mp)}$ decays with a Dalitz plot analysis of $D$ decays to $K_{S}^{0} π^{+} π^{-}$ and $K_{S}^{0} K^{+} K^{-}$ , Phys. Rev. D 78, 034023 (2008).
B. Aubert et al. (BABAR Collaboration, Amplitude analysis of the decay $D^{0} \to K^{-} K^{+} π^{0}$ , Phys. Rev. D 76, 011102 (2007).
R. Aaij et al. (LHCb Collaboration), Studies of the resonance structure in $D^{0} \to K_{S}^{0} K^{\pm} π^{\mp}$ decays, Phys. Rev. D 93, 052018 (2016).
M. Ablikim et al. (BESIII Collaboration), Study of the decay $D_{s}^{+} \to K_{S}^{0} K_{S}^{0} π^{+}$ and observation an isovector partner to $f_{0} (1710)$ , Phys. Rev. D 105, L051103 (2022).
M. Ablikim et al. (BESIII Collaboration), Observation of an $a_{0}$ -like state with mass of 1.817 GeV in the study of $D_{s}^{+} \to K_{S}^{0} K^{+} π^{0}$ decays, Phys. Rev. Lett. 129, 182001 (2022).
J. P. Lees et al. (BABAR Collaboration, Observation of the rare decay $B^{+} \to K^{+} π^{0} π^{0}$ and measurement of the quasi-two body contributions $B^{+} \to K^{*} (892)^{+} π^{0}$ , $B^{+} \to f_{0} (980) K^{+}$ and $B^{+} \to χ_{c 0} K^{+}$ , Phys. Rev. D 84, 092007 (2011).
J. P. Lees et al. (BABAR Collaboration, Evidence for $C P$ violation in $B^{+} \to K^{*} (892)^{+} π^{0}$ from a Dalitz plot analysis of $B^{+} \to K_{S}^{0} π^{+} π^{0}$ decays, Phys. Rev. D 96, 072001 (2017).
K. Abe et al. (Belle Collaboration), Measurements of branching fractions and decay amplitudes in $B \to J / ψ K^{*}$ decays, Phys. Lett. B 538, 11 (2002).
A. Garmash et al. (Belle Collaboration), Dalitz analysis of three-body charmless $B^{0} \to K^{0} π^{+} π^{-}$ decay, Phys. Rev. D 75, 012006 (2007).
B. Aubert et al. (BABAR Collaboration, Time-dependent amplitude analysis of $B^{0} \to K_{S}^{0} π^{+} π^{-}$ , Phys. Rev. D 80, 112001 (2009).
J. P. Lees et al. (BABAR Collaboration, Amplitude analysis of $B^{0} \to K^{+} π^{-} π^{0}$ and evidence of direct $C P$ violation in $B \to K^{*} π$ decays, Phys. Rev. D 83, 112010 (2011).
R. Aaij et al. (LHCb Collaboration), Amplitude analysis of the decay ${\bar{B}}^{0} \to K_{S}^{0} π^{+} π^{-}$ and first observation of the $C P$ asymmetry in ${\bar{B}}^{0} \to K^{*} (892)^{-} π^{+}$ , Phys. Rev. Lett. 120, 261801 (2018).
P. del Amo Sanchez et al. (BABAR Collaboration, Analysis of the $D^{+} \to K^{-} π^{+} e^{+} ν_{e}$ decay channel, Phys. Rev. D 83, 072001 (2011).
M. Ablikim et al. (BESIII Collaboration), Study of $D^{+} \to K^{-} π^{+} e^{+} ν_{e}$ , Phys. Rev. D 94, 032001 (2016).
G. Bonvicini et al. (CLEO Collaboration), Dalitz plot analysis of the $D^{+} \to K^{-} π^{+} π^{+}$ decay, Phys. Rev. D 78, 052001 (2008).
J. M. Link et al. (FOCUS Collaboration), The $K^{-} π^{+}$ S-wave from the $D^{+} \to K^{-} π^{+} π^{+}$ decay, Phys. Lett. B 681, 14 (2009).
M. Ablikim et al. (BESIII Collaboration), Amplitude analysis of the $D^{+} \to K_{S}^{0} π^{+} π^{0}$ Dalitz plot, Phys. Rev. D 89, 052001 (2014).
M. Ablikim et al. (BESIII Collaboration), Amplitude analysis and branching fraction measurement of the decay $D^{+} \to K_{S}^{0} π^{+} π^{0} π^{0}$ , J. High Energy Phys. 09 (2023) 077.
P. Rubin et al. (CLEO Collaboration), Search for $C P$ violation in the Dalitz-plot analysis of $D^{\pm} \to K^{+} K^{-} π^{\pm}$ , Phys. Rev. D 78, 072003 (2008).
N. Lowrey et al. (CLEO Collaboration), Analysis of the decay $D^{0} \to K_{S}^{0} π^{0} π^{0}$ , Phys. Rev. D 84, 092005 (2011).
D. M. Asner et al. (CLEO Collaboration), Determination of the $D^{0} \to K^{+} π^{-}$ relative strong phase using quantum-correlated measurements in $e^{+} e^{-} \to D^{0} {\bar{D}}^{0}$ at CLEO, Phys. Rev. D 78, 012001 (2008).
P. del Amo Sanchez et al. (BABAR Collaboration, Dalitz plot analysis of $D_{s}^{+} \to K^{+} K^{-} π^{+}$ , Phys. Rev. D 83, 052001 (2011).
M. Ablikim et al. (BESIII Collaboration), Amplitude analysis and branching fraction measurement of $D_{s}^{+} \to K^{+} K^{-} π^{+}$ , Phys. Rev. D 104, 012016 (2021).
J. M. Link et al. (FOCUS Collaboration), Study of the doubly and singly Cabibbo suppressed decays $D^{+} \to K^{+} π^{+} π^{-}$ and $D_{s}^{+} \to K^{+} π^{+} π^{-}$ , Phys. Lett. B 601, 10 (2004).
M. Ablikim et al. (BESIII Collaboration), Amplitude analysis and branching fraction measurement of the decay $D_{s}^{+} \to K^{+} π^{+} π^{-}$ , J. High Energy Phys. 08 (2022) 196.
M. Ablikim et al. (BESIII Collaboration), Amplitude analysis and branching-fraction measurement of $D_{s}^{+} \to K_{S}^{0} π^{+} π^{0}$ , J. High Energy Phys. 06 (2021) 181.
A. Garmash et al. (Belle Collaboration), Evidence for large direct $C P$ violation in $B^{\pm} \to ρ (770)^{0} K^{\pm}$ from analysis of the three-body charmless $B^{+ -} \to K^{\pm} π^{\pm} π^{\mp}$ decay, Phys. Rev. Lett. 96, 251803 (2006).
B. Aubert et al. (BABAR Collaboration, Evidence for direct $C P$ violation from Dalitz-plot analysis of $B^{\pm} \to K^{\pm} π^{\mp} π^{\pm}$ , Phys. Rev. D 78, 012004 (2008).

Phys. Rev. D 113, L011503– Published 30 January, 2026

Vol. 113, Iss. 1 — 1 January 2026

Received 7 May 2025
Accepted 5 December 2025

DOI: https://doi.org/10.1103/s87z-1978

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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Precise $K^{*} (892) \to K π$ branching fractions

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Precise K*(892)→Kπ branching fractions

Abstract

Physics Subject Headings (PhySH)

Article Text

References (45)

Precise $K^{*} (892) \to K π$ branching fractions