arXiv subjects

P. Adlarson

Publications and source records attributed to P. Adlarson.

At least 325 records · Page 18Linked to original sources

arXiv2025

Study of the electromagnetic Dalitz decay $J/ψ\to e^+e^- π^0$

We report the first measurement of the di-electron invariant mass dependent transition form factor in the electromagnetic Dalitz decay $J/ψ\to e^+e^- π^0$ using $(10087 \pm 44) \times 10^6$ $J/ψ$ events collected by the BESIII detector. A clear $ρ-ω$ interference structure is observed, consistent with the pion form factor, which offers a novel approach to extract the hadronic vacuum polarization contribution to the anomalous muon magnetic moment ($a_μ$) and refine the predictions of the Vector Meson Dominance (VMD) model and hadronic light-by-light contribution to $a_μ$. By taking into account the contribution of this $ρ-ω$ interference structure, the branching fraction of $J/ψ\to e^+e^- π^0$ in the full $e^+e^-$ invariant mass range is also measured for the first time to be $(8.06 \pm 0.31 (\rm{stat}) \pm 0.38 (\rm{syst}))\times 10^{-7}$, approximately twice the non-resonant VMD prediction.

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arXiv2025

Improved measurement of absolute branching fraction of the inclusive decay $Λ_{c}^{+} \to K_{S}^{0} X$

By analyzing $4.5$ fb$^{-1}$ of $e^{+}e^{-}$ collision data accumulated with the BESIII detector at center-of-mass energies ranging from $4599.53$ MeV to $4698.82$ MeV, we report the measurement of the absolute branching fraction (BF) of the inclusive decay $Λ_{c}^{+} \to K_{S}^{0} X$ using the double-tag technique. The result is $\mathcal{B}(Λ_{c}^{+} \to K_{S}^{0} X)=(10.9\pm0.2\pm0.1)\%$, where the first uncertainty is statistical and the second is systematic. This result indicates that there are still undiscovered decay channels containing $K_{S}^{0}$ in the final state with a combined BF of $(3.1\pm0.4)\%$. The BF of the inclusive decay $Λ_{c}^{+} \to \overline{K}^{0} / K^{0} X$ is calculated to be $\mathcal{B}(Λ_{c}^{+} \to \overline{K}^{0} / K^{0} X)=(21.8 \pm0.4 \pm0.2 \pm1.1)\%$, where the third uncertainty accounts for a possible difference between $\mathcal{B}(Λ_{c}^{+} \to K_{S}^{0} X)$ and $\mathcal{B}(Λ_{c}^{+} \to K_{L}^{0} X)$. The result is in agreement with the prediction of the statistical isospin model.

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arXiv2025

Search for charge-parity violation in semileptonically tagged $D^{0} \to K^{+} π^{-}$ decays

An analysis of the flavour oscillations of the charmed neutral meson is presented. The ratio of $D^{0} \to K^{+} π^{-}$ and $D^{0} \to K^{-} π^{+}$ decay rates is measured as a function of the decay time of the $D^{0}$ meson and compared with the charge-conjugated system to search for charge-parity violation. The meson flavour at production is double-tagged by the charges of the muon and pion in the preceding $\overline{B} \to D^{*}(2010)^{+} μ^{-} X$ and ${{D^{*}(2010)^{+}} \to D^{0}π^{+}}$ decays, respectively. These decays are selected from proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of ${13\,\text{TeV}}$ and corresponding to an integrated luminosity of ${5.4\,\text{fb}^{-1}}$. The flavour oscillation parameters, relating to the differences in mass and width of the mass eigenstates, are found to be ${y^\prime=(5.8\pm1.6)\times10^{-3}}$ and ${(x^\prime)^2=(0.0\pm1.2)\times10^{-4}}$. No evidence for charge-parity violation is seen either in the flavour oscillations or in the decay, where the direct charge-parity asymmetry is measured to be ${A_{D}=(2.3\pm1.7)\,{\%}}$.

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arXiv2025

Measurement of the $η$ transition form factor through $η' \rightarrow π^+π^-η$ decay

Based on a sample of $(1.0087\pm0.0044)\times10^{10}$ $J/ψ$ events collected at BESIII, the transition form factor of the $η$ meson is extracted by analyzing $J/ψ\toγη',~η'\toπ^+π^-η,~η\toγl^+l^-$ ($l$=$e$, $μ$) events. The measured slope of the transition form factor is $Λ^{-2}=1.645\pm0.093_{\rm stat.}\pm {0.024_{\rm sys.}}$ (GeV/$c^2$)$^{-2}$ for the di-electron channel and $Λ^{-2}=1.645\pm0.343_{\rm stat.}\pm0.017_{\rm sys.}$ (GeV/$c^2$)$^{-2}$ for the di-muon channel. The branching fractions for $η\rightarrowγe^+e^-$ and $η\rightarrowγμ^+μ^-$ are measured to be $\mathcal{B}(η\toγe^+e^-)=(6.79\pm0.04_{\rm stat.}\pm0.36_{\rm sys.})\times 10^{-3}$ and $\mathcal{B}(η\toγμ^+μ^-)=(2.97\pm0.11_{\rm stat.}\pm0.07_{\rm sys.})\times 10^{-4}$. By combining with the results based on the $J/ψ\toγη,~η\toγe^+e^-$ events from the previous BESIII measurement, we determine $Λ^{-2}=1.707\pm0.076_{\rm stat.}\pm0.029_{\rm sys.}$ (GeV/$c^2$)$^{-2}$ and $\mathcal{B}(η\toγe^+e^-)=(6.93\pm0.28_{\rm tot.})\times 10^{-3}$. In addition, we search for the dark photon ($A'$) using the combined events. No significant signal is observed, and the upper limits on $\mathcal{B}(η\toγA',~A'\to e^+e^-)$ are set at 90\% confidence level for different $A'$ mass hypotheses.

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arXiv2025

First observation of quantum correlations in $e^+e^-\to XD\bar{D}$ and $C$-even constrained $D\bar{D}$ pairs

The study of meson pairs produced with quantum correlations gives direct access to parameters that are challenging to measure in other systems. In this Letter, the existence of quantum correlations due to charge-conjugation symmetry $C$ are demonstrated in $D\bar{D}$ pairs produced through the processes $e^+e^-\to D\bar{D}$, $e^+e^- \to D^{*}\bar{D}$, and $e^+e^- \to D^{*} \bar{D}^*$, where the lack of charge superscripts refers to an admixture of neutral-charm-meson particle and antiparticle states, using $7.13 \text{ fb}^{-1}$ of $e^+e^-$ collision data collected by the BESIII experiment between center-of-mass energies of $4.13-4.23 \text{ GeV}$. Processes with either $C$-even or $C$-odd constraints are identified and separated. A procedure is presented that harnesses the entangled production process to enable measurements of $D^0$-meson hadronic parameters. This study provides the first confirmation of quantum correlations in $e^+e^-\to X D\bar{D}$ processes and the first observation of a $C$-even constrained $D\bar{D}$ system. The procedure is applied to measure $δ^{D}_{Kπ}$, the strong phase between the $D^0\to K^-π^+$ and $\bar{D}^0\to K^-π^+$ decay amplitudes, which results in the determination of $δ^{D}_{Kπ}=\left(192.8^{+11.0 + 1.9}_{-12.4 -2.4}\right)^\circ$. The potential for measurements of other hadronic decay parameters and charm mixing with these and future datasets is also discussed.

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arXiv2025

A novel measurement of the strong-phase difference between $D^0\to K^-π^+$ and $\bar{D}^0\to K^-π^+$ decays using $C$-even and $C$-odd quantum-correlated $D\bar{D}$ pairs

A novel measurement technique of strong-phase differences between the decay amplitudes of $D^0$ and $\bar{D}^0$ mesons is introduced which exploits quantum-correlated $D\bar{D}$ pairs produced by $e^+e^-$ collisions at energies above the $ψ(3770)$ production threshold, where $D\bar{D}$ pairs are produced in both even and odd eigenstates of the charge-conjugation symmetry. Employing this technique, the first determination of a $D^0$-$\bar{D^0}$ relative strong phase is reported with such data samples. The strong-phase difference between $D^0\to K^-π^+$ and $\bar{D}^0\to K^-π^+$ decays, $δ^{D}_{Kπ}$, is measured to be $δ^{D}_{Kπ}=\left(192.8^{+11.0 + 1.9}_{-12.4 -2.4}\right)^\circ$, using a dataset corresponding to an integrated luminosity of 7.13 $\text{fb}^{-1}$ collected at center-of-mass energies between $4.13-4.23 \text{ GeV}$ by the BESIII experiment.

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arXiv2025

Search for $η_{1}(1855)$ in $χ_{cJ}\toηηη^{\prime}$ decays

Based on a sample of $2.7\times10^{9}$ $ψ(3686)$ events collected by the BESIII detector operating at the BEPCII collider, an analysis of the decay $ψ(3686)\toγχ_{cJ}, χ_{cJ}\toηηη^{\prime}$ is performed. The decay modes $χ_{c1}$ and $χ_{c2}\toηηη^{\prime}$ are observed for the first time, and their corresponding branching fractions are determined to be $\mathcal{B}(χ_{c1}\toηηη^{\prime}) = (1.40\, \pm 0.13\, (\text{stat.}) \pm 0.09\, (\text{sys.})) \times 10^{-4}$ and $\mathcal{B}(χ_{c2}\toηηη^{\prime}) = (4.18\, \pm 0.84\, (\text{stat.}) \pm 0.48\, (\text{sys.})) \times 10^{-5}$. An upper limit on the branching fraction of $χ_{c0}\toηηη^{\prime}$ is set as $2.59 \times 10^{-5}$ at 90\% confidence level (CL). A partial wave analysis (PWA) of the decay $χ_{c1}\toηηη^{\prime}$ is performed to search for the $1^{-+}$ exotic state $η_1(1855)$. The PWA result indicates that the structure in the $ηη^{\prime}$ mass spectrum is mainly attributed to the $f_0(1500)$, while in the $ηη$ mass spectrum, it is primarily the $0^{++}$ phase space. The upper limit of $\mathcal{B}(χ_{c1}\toη_{1}(1855)η) \cdot \mathcal{B}(η_{1}(1855)\toηη^{\prime})< 9.79 \times 10^{-5}$ is set based on the PWA at 90\% CL.

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arXiv2025

Study of $\itΛ_{\it{b}}^\rm{0}$ and $\itΞ_{\it{b}}^\rm{0}$ decays to $\itΛ h^+h^{'-}$ and evidence for $CP$ violation in $\itΛ_{\it{b}}^\rm{0}\to\itΛ K^+K^-$ decays

A study of $\itΛ_{\it{b}}^\rm{0}$ and $\itΞ_{\it{b}}^\rm{0}$ decays to $\itΛ h^{+} h^{\prime -}$ $(h^{(\prime)}=π, K)$ is performed using $pp$ collision data collected by the LHCb experiment during LHC Runs 1$-$2, corresponding to an integrated luminosity of $9~\rm{fb}^{-1}$. The branching fractions for these decays are measured using the $\itΛ_{\it{b}}^\rm{0}\to\itΛ_{\it{c}}^+(\to\itΛπ^+)π^-$ decay as control channel. The decays $\itΛ_{\it{b}}^\rm{0}\to\itΛπ^+π^-$ and $\itΞ_{\it{b}}^\rm{0}\to\itΛK^-π^+$ are observed for the first time. For decay modes with sufficient signal yields, $CP$ asymmetries are measured in the full and localized regions of the final-state phase space. Evidence is found for $CP$ violation in the $\itΛ_{\it{b}}^\rm{0}\to\itΛK^+K^-$ decay, interpreted as originating primarily from an asymmetric $\itΛ_{\it{b}}^\rm{0} \to \it{N}^{*+} \it{K}^-$ decay amplitude. The measured $CP$ asymmetries for the other decays are compatible with zero.

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arXiv2025

Study of $D_{s1}(2460)^{+}\to D_{s}^{+}π^{+}π^{-}$ in $B\to {\bar{D}}^{(*)}D_{s}^{+}π^{+}π^{-}$ decays

An amplitude analysis of the $D_{s1}(2460)^+\to D_{s}^{+}π^{+}π^{-}$ transition is performed simultaneously in $B^{0}\to D^{-}D_{s}^{+}π^{+}π^{-}$, $B^{+}\to{\bar{D}}^{0} D_{s}^{+}π^{+}π^{-}$, and $B^{0}\to D^{*-}D_{s}^{+}π^{+}π^{-}$ decays. The study is based on a data sample of proton-proton collisions recorded with the LHCb detector at centre-of-mass energies of $\sqrt{s}=7,8,$ and $13\,$TeV, corresponding to a total integrated luminosity of $9\,\rm{fb}^{-1}$. A clear double-peak structure is observed in the $m(π^{+}π^{-})$ spectrum of the $D_{s1}(2460)^{+}\to D_{s}^{+}π^{+}π^{-}$ decay. The data can be described either with a model including $f_0(500)$, $f_0(980)$ and $f_2(1270)$ resonances, in which the contributions of $f_0(980)$ and $f_2(1270)$ are unexpectedly large, or with a model including $f_0(500)$, a doubly charged open-charm tetraquark state $T_{c\bar{s}}^{++}$ and its isospin partner $T_{c\bar{s}}^{0}$. If the former is considered implausible, the $T_{c\bar{s}}$ states are observed with high significance, and the data are consistent with isospin symmetry. When imposing isospin constraints between the two $T_{c\bar{s}}$ states, their mass and width are determined to be $2327\pm13\pm13\,$MeV and $96\pm16\,^{+170}_{-23}\,$MeV, respectively, where the first uncertainty is statistical and the second is systematic. The mass is slightly below the $DK$ threshold, and a spin-parity of $0^+$ is favoured with high significance.

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arXiv2025

Search for $e^+e^-\to K_S^0 K_S^0 h_c$

Using $e^+e^-$ collision data at 13 center-of-mass energies ranging from 4.600 to 4.950 GeV collected with the BESIII detector, we search for the unmeasured $e^+e^-\to K_S^0 K_S^0 h_c$ process . No significant signal is observed, and the upper limits of the Born cross sections at each center-of-mass energy are presented.

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arXiv2025

Search for resonance-enhanced $CP$ and angular asymmetries in the $Λ^+_{c}\to pμ^+μ^-$ decay at LHCb

The first measurement of the $CP$ asymmetry of the decay rate ($A_{CP}$) and the $CP$ average ($ΣA_{\text{FB}}$) and $CP$ asymmetry ($ΔA_{\text{FB}}$) of the forward-backward asymmetry in the muon system of $\mathitΛ^+_c\to pμ^+μ^-$ decays is reported. The measurement is performed using a data sample of proton-proton collisions, recorded by the LHCb experiment from 2016 to 2018 at a center-of-mass energy of 13$\text{ TeV}$, which corresponds to an integrated luminosity of 5.4$\text{ fb}^{-1}$. The asymmetries are measured in two regions of dimuon mass near the $ϕ$-meson mass peak. The dimuon-mass integrated results are \begin{align*} A_{CP} &= (-1.1 \pm 4.0 \pm 0.5)\%,\\ ΣA_{\text{FB}} &= (\phantom{-}3.9 \pm 4.0 \pm 0.6)\%,\\ ΔA_{\text{FB}} &= (\phantom{-}3.1 \pm 4.0 \pm 0.4)\%, \end{align*} where the first uncertainty is statistical and the second systematic. The results are consistent with the conservation of $CP$ symmetry and the Standard Model expectations.

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arXiv2025

Observation of the $W$-annihilation process $D_s^+ \to ωρ^+$ and measurement of $D_s^+ \to ϕρ^+$ in $D^+_s\to π^+π^+π^-π^0π^0$ decays

We present the first amplitude analysis and branching fraction measurement of the decay $D^+_s\to π^+π^+π^-π^0π^0$, using $e^+e^-$ collision data collected with the BESIII detector at center-of-mass energies between 4.128 and 4.226 GeV corresponding to an integrated luminosity of 7.33 fb$^{-1}$, and report the first observation of the pure $W$-annihilation decay $D_s^+ \to ωρ^+$ with a branching fraction of $(0.99\pm0.08_{\rm stat}{\ ^{+0.05}_{-0.07}}_{\rm syst})\%$. %The absolute branching fraction is measured to be $(0.99\pm0.08_{\rm stat}\pm0.07_{\rm syst})\%$. In comparison to the low significance of the $\mathcal{D}$ wave in the decay $D_s^+ \to ϕρ^+$, the dominance of the $\mathcal{D}$ wave over the $\mathcal{S}$ and $\mathcal{P}$ waves, with a fraction of $(51.85\pm7.28_{\rm stat}{\ ^{+4.83}_{-7.90}}_{\rm syst})\%$ observed in the decay $D_s^+ \to ωρ^+$, provides crucial information for the``polarization puzzle", as well as for the understanding of charm meson decays. The branching fraction of $D^+_s\to π^+π^+π^-π^0π^0$ is measured to be ($4.41\pm0.15_{\rm stat}\pm0.13_{\rm syst}$)\%. Moreover, the branching fraction of $D_s^+ \to ϕρ^+$ is measured to be $(3.98\pm0.33_{\rm stat}{\ ^{+0.21}_{-0.19}}_{\rm syst})\%$, and the $R_ϕ= {\mathcal{B}(ϕ\toπ^+π^-π^0)}/{\mathcal{B}(ϕ\to K^+K^-)}$ is determined to be $(0.222\pm0.019_{\rm stat}{\ ^{+0.016}_{-0.016}}_{\rm syst}$), which is consistent with the previous measurement based on charm meson decays, but deviates from the results from $e^+e^-$ annihilation and $K$-$N$ scattering experiments by more than 3$σ$.

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arXiv2025

Comprehensive analysis of local and nonlocal amplitudes in the $B^0\rightarrow K^{*0}μ^+μ^-$ decay

A comprehensive study of the local and nonlocal amplitudes contributing to the decay $B^0\rightarrow K^{*0}(\to K^+π^-) μ^+μ^-$ is performed by analysing the phase-space distribution of the decay products. The analysis is based on $pp$ collision data corresponding to an integrated luminosity of 8.4fb$^{-1}$ collected by the LHCb experiment. This measurement employs for the first time a model of both one-particle and two-particle nonlocal amplitudes, and utilises the complete dimuon mass spectrum without any veto regions around the narrow charmonium resonances. In this way it is possible to explicitly isolate the local and nonlocal contributions and capture the interference between them. The results show that interference with nonlocal contributions, although larger than predicted, only has a minor impact on the Wilson Coefficients determined from the fit to the data. For the local contributions, the Wilson Coefficient $C_9$, responsible for vector dimuon currents, exhibits a $2.1σ$ deviation from the Standard Model expectation. The Wilson Coefficients $C_{10}$, $C_{9}'$ and $C_{10}'$ are all in better agreement than $C_{9}$ with the Standard Model and the global significance is at the level of $1.5σ$. The model used also accounts for nonlocal contributions from $B^{0}\to K^{*0}\left[τ^+τ^-\to μ^+μ^-\right]$ rescattering, resulting in the first direct measurement of the $b sττ$ vector effective-coupling $C_{9τ}$.

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arXiv2025

Observation of $χ_{cJ}\to 3K_S^0K^\pmπ^\mp$

By analyzing $(2712.4\pm14.3)\times10^6$ $ψ(3686)$ events collected with the BESIII detector operating at the BEPCII collider, the decays $χ_{c0,1,2} \to 3K_S^0K^\pmπ^\mp$ are observed for the first time with statistical significances greater than $10σ$. The branching fractions of these decays are determined to be $\mathcal{B}(χ_{c0}\to 3K_S^0K^\pmπ^\mp )=(7.95\pm0.50\pm0.65)\times10^{-5},$ $\mathcal{B}(χ_{c1}\to 3K_S^0K^\pmπ^\mp)=(2.62\pm0.08\pm0.19)\times10^{-4},$ and $\mathcal{B}(χ_{c2}\to 3K_S^0K^\pmπ^\mp)=(1.72\pm0.07\pm0.15)\times10^{-4},$ where the first uncertainties are statistical and the second systematic.

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arXiv2025

Test of local realism via entangled $Λ\barΛ$ system

The non-locality of quantum correlations is a fundamental feature of quantum theory. The Bell inequality serves as a benchmark for distinguishing between predictions made by quantum theory and local hidden variable theory (LHVT). Recent advancements in photon-entanglement experiments have addressed potential loopholes and have observed significant violations of variants of Bell inequality. However, examples of Bell inequalities violation in high energy physics are scarce. In this study, we utilize $(10.087\pm0.044)\times10^{9}$ $J/ψ$ events collected with the BES-III detector at the BEPCII collider, performing non-local correlation tests using the entangled hyperon pairs. The massive-entangled $Λ\barΛ$ systems are formed and decay through strong and weak interactions, respectively. Through measurements of the angular distribution of $p\bar{p}$ in $J/ψ\to γη_c$ and subsequent $η_c\toΛ(pπ^-)\barΛ(\bar{p}π^{+})$ cascade decays, a significant violation of LHVT predictions is observed. The exclusion of LHVT is found to be statistically significant at a level exceeding $5.2σ$ in the testing of three Bell-like inequalities.

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arXiv2025

Search for $D^0$ meson decays to $π^+ π^- e^+ e^-$ and $K^+ K^- e^+ e^-$ final states

A search for $D^0$ meson decays to the $π^+π^-e^+e^-$ and $K^+K^-e^+e^-$ final states is reported using a sample of proton-proton collisions collected by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb$^{-1}$. The decay $D^0 \rightarrow π^+π^-e^+e^-$ is observed for the first time when requiring that the two electrons are consistent with coming from the decay of a $ϕ$ or $ρ^0/ω$ meson. The corresponding branching fractions are measured relative to the $D^0 \rightarrow K^-π^-[e^+e^-]_{ρ^0/ω}$ decay, where the two electrons are consistent with coming from the decay of a $ρ^0$ or $ω$ meson. No evidence is found for the $D^0 \rightarrow K^+K^-e^+e^-$ decay and world-best limits are set on its branching fraction. The results are compared to, and found to be consistent with, the branching fractions of the $D^0 \rightarrow π^+π^-μ^+μ^-$ and $D^0 \rightarrow K^+K^-μ^+μ^-$ decays recently measured by LHCb and confirm lepton universality at the current precision.

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arXiv2025

Observation of an Altered $a_{0}(980)$ Line-shape in $D^{+} \rightarrow π^{+}ηη$ due to the Triangle Loop Rescattering Effect

Using 20.3~${\rm fb}^{-1}$ of $e^{+}e^{-}$ collision data taken with the BESIII detector at the center-of-mass energy 3.773~GeV, we report the first amplitude analysis of the hadronic decay $D^{+} \rightarrow π^{+}ηη$. The intermediate process $D^{+} \to a_{0}(980)^{+}η, a_{0}(980)^{+} \to π^{+}η$ is observed and is found to be the only component and its branching fraction is measured to be $(3.67\pm0.12_{\mathrm{stat.}}\pm 0.06_{\mathrm{syst.}})\times 10^{-3}$. Unlike the $a_{0}(980)$ line-shape observed in the decays of charmed mesons to $a_{0}(980)π$ and in the decay $D^{0} \to a_{0}(980)^{-}e^{+}ν_{e}$, where the low-mass side of the $a_0(980)$ is wider than the high-mass side, the $a_{0}(980)$ line-shape in $D^{+} \to a_{0}(980)^{+}η$ is found to be significantly altered, with the high-mass side being wider than the low-mass side. We establish that the $a_0(980)$ line-shape arises from the triangle loop rescattering of $D^+ \to \bar{K}_0^*(1430)^0K^+ \to a_0(980)^+ η$ and $D^+ \to K_0^*(1430)^+\bar{K}^0 \to a_0(980)^+ η$ with a significance of 5.8$σ$. This is the first experimental confirmation of the triangle loop rescattering effect.

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arXiv2025

Study of light-meson resonances decaying to $K^0_{\rm S} K π$ in the $B \to (K^0_{\rm S} K π) K$ channels

A study is presented of $B^+ \to K^0_{\rm S} K^- π^+ K^-$ and $B^+ \to K^0_{\rm S} K^+ π^- K^+$ decays based on the analysis of proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of $9 fb^{-1}$. The $K^0_{\rm S} K π$ invariant-mass distributions of both $B^+$ decay modes show, in the $m(K^0_{\rm S} K π)<1.85$ GeV mass region, large activity which is resolved using an amplitude analysis. A simple model, were $J^{PC}$ amplitudes are described by multiple Breit--Wigner functions with appropriate angular distributions provides a good description of the experimental data. In this approach a complex mixture of $J^{PC}=0^{-+}, 1^{++}$ and $1^{+-}$ amplitudes is observed that is dominated by $η(1405)$, $η(1470)$, $η(1760)$, $f_1(1285)$, $f_1(1420)$ and $h_1(1405)$ resonances. The $K^0_{\rm S} K π$ Dalitz plots are dominated by asymmetric crossing $K^* \bar{K}$ bands which are different for the two $B^+$ decay modes. This is due to a different interference pattern between the $1^{++}$ and $1^{+-}$ amplitudes in the two channels. Branching fractions are measured for each resonant contribution.

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