arXiv subjects

J. Cheng

Publications and source records attributed to J. Cheng.

At least 55 records · Page 3Linked to original sources

arXiv2026

Quantifying the Role of 3D Fault Geometry Complexities on Slow and Fast Earthquakes

Traditional models of slow slip events (SSEs) oversimplify fault geometry, although imaging shows subduction faults are segmented and complex. We examine how fault interactions control slip behavior using 3-D quasi-dynamic earthquake sequence simulations of two parallel faults with uniform rate-weakening friction accelerated by hierarchical matrices. Four regimes emerge-periodic earthquakes, coexisting SSEs and earthquakes, only SSEs, and complex sequences-whereas with the same friction condition a single planar fault produces only earthquakes. We quantify interaction using the maximum Coulomb stress induced on a target fault by a spatially uniform unit stress drop on a neighboring fault. Because the stress drop is normalized, the metric depends only on geometry and is independent of friction, allowing extension to arbitrary fault systems. SSEs occur only at intermediate fault interaction strengths. At low interaction strengths, the system produces regular, periodic earthquakes. At high interaction strengths, fault interactions generate complex earthquake sequences with irregular recurrence and variable magnitudes. Simulations reproduce observed moment-duration scaling and show sensitivity to detection thresholds. These results demonstrate geometric complexity alone generates both slow and fast earthquakes through evolving traction heterogeneity.

physics.geo-ph↗

arXiv2026

Observation of $Ξ(1530)^0$ Polarization and Determination of Its Electric and Magnetic Moments in $ψ(3686)\toΞ(1530)^0\barΞ(1530)^0$

Using the data sample of $2.7\times10^9$ $ψ(3686)$ events collected with the BESIII detector at the BEPCII collider, we present an observation of the $Ξ(1530)^0$ polarization in the decay $ψ(3686)\toΞ(1530)^0\barΞ(1530)^0$ with a significance larger than $20σ$ compared with all other tested hypotheses. The helicity amplitudes for the process $ψ(3686)\toΞ(1530)^0\barΞ(1530)^0$ and the moduli of form factors including electric charge, magnetic dipole, electric quadrupole, and magnetic octupole are measured for the first time by performing an angular distribution analysis. Additionally, the polarization correlations between $Ξ(1530)^0$ and $\barΞ(1530)^0$ are measured.

hep-ex↗

arXiv2026

Study of the $e^+e^-\to π^+π^-D_s^+D_s^-$ process from $\sqrt{s}$ = 4.42 to 4.95 GeV at BESIII

Based on $8.5~{\rm fb}^{-1}$ of $e^+e^-$ collision data collected at center-of-mass energies between 4.42 and 4.95 GeV with the BESIII detector at the BEPCII storage ring, we investigate the process $e^+e^-\to π^+π^-D_s^+D_s^-$. With no significant signal observed, upper limits on the Born cross sections of $e^+e^-\to π^+π^-D_s^+D_s^-$ at each energy value are determined at the 90% confidence level. Additionally, a search for intermediate charmonium-like resonances is performed in the $M(D_s^+D_s^-)$ invariant-mass spectrum, but no significant resonant structures are observed with the current statistics.

hep-ex↗

arXiv2026

Inclusive jet cross section in $pp$ collisions at $\sqrt{s} = 200$ and $510$ GeV

Jets are collimated clusters of particles formed by the hadronization of partons following a hard interaction. In proton-proton ($pp$) collisions at the Relativistic Heavy Ion Collider (RHIC), jet production is dominated by $gg$ and $qg$ partonic processes, allowing us to directly probe the gluon parton distribution function (PDF) in the proton in a way complementary to deep inelastic scattering. In this paper, we report the double-differential inclusive-jet cross sections as a function of jet transverse momentum, $p_{\rm T}$, and pseudorapidity, $η$, at center-of-mass energies $\sqrt{s} = 200$ and $510$~GeV, from $pp$ collisions studied with the STAR detector. The jet $p_{\rm T}$ is corrected for underlying event contributions by applying an off-axis cone method. At mid-pseudorapidity, $|η| < 0.9$, the kinematic coverage of our data extends to $0.07 < x_{\rm T} \text{ (}= 2p_{\rm T}{} / \sqrt{s} \text{)} < 0.5$ and $0.03 < x_{\rm T} < 0.31$ at $\sqrt{s} = 200$~and 510 GeV, respectively, where the gluon PDF is poorly constrained by the TeV-scale $pp$~($p\bar{p}$) colliders. The inclusive jet cross sections are compared to the next-to-next-to-leading order perturbative quantum chromodynamics calculations using several recent PDF sets as inputs. These results will further constrain the gluon PDF, help tune Monte Carlo generators, and provide critical reference data needed to study the quark-gluon plasma.

hep-ex↗

arXiv2026

Observation of $ψ(3770)\to p\bar p$ and Measurement of Electromagnetic Form Factors of Proton at $\sqrt{s} = 3.510-4.946$ GeV

We search for possible charmonium(-like) states decaying into the $p\bar{p}$ final state by studying the Born cross sections of the $e^+e^-\to p\bar{p}$ reaction, and we determine the proton electromagnetic form factors by analyzing the proton angular distribution. The measurement is performed using a sample of $e^+e^-$ collision data collected at 47 center-of-mass energies from 3.510 to 4.946 GeV, corresponding to an integrated luminosity of 26 fb$^{-1}$, recorded by the BESIII detector collected at the BEPCII collider. The decay $ψ(3770)\to p\bar{p}$ is observed with a significance of 6.6$σ$ including systematic uncertainties. Furthermore, a structure near 4.2 GeV is observed with significances of $4.6σ$ or $4.8σ$ for the $ψ(4160)$ or $Y(4230)$ hypotheses including systematic uncertainties, respectively; these interpretations cannot presently be distinguished. In addition, the moduli of the form factor ratios $|G_{E}/G_{M}|$ and of the magnetic form factors $|G_{M}|$ are extracted by analyzing the proton polar angle distribution with higher precision at large time-like squared momentum transfer. These results provide important experimental insights into both the decay mechanisms of charmonium(-like) states in the open charm region and the internal structure of proton.

hep-ex↗

arXiv2026

Measurement of Born cross sections for $e^+e^-\to p\bar p$ at $\sqrt{s} =3.510-4.946$ GeV

We report a measurement of the Born cross section and the effective form factor for the $e^+e^-\to p\bar{p}$ reaction at 47 center-of-mass energies between 3.510 and 4.946 GeV. The measurement is performed using the energy-scan technique and is based on data corresponding to an integrated luminosity of 26 fb$^{-1}$ collected with the BESIII detector at the BEPCII collider. For the first time, the moduli of the electromagnetic form factor ratio $|G_{E}/G_{M}|$ and of the magnetic form factor $|G_{M}|$ are determined with high precision by analyzing the distribution of the polar angle of the proton at a large timelike momentum transfer. These results provide essential insights into the nature of charmonium(-like) states above the open-charm threshold and the dynamics underlying the proton electromagnetic form factors.

hep-ex↗

arXiv2026

Search for the charged lepton flavor violating decay $η\to e^{\pm}μ^{\mp}$

Based on $(10.087 \pm 0.044) \times 10^{9}~J/ψ$ events collected at the center-of-mass energy $\sqrt{s} = 3.097$~GeV with the BESIII detector, we search for the charged lepton flavor violating decay $η\to e^{\pm}μ^{\mp}$ through the process $J/ψ\to γη'$ with $η' \to π^{+} π^{-} η$. No signal is observed, and an upper limit on the branching fraction is determined to be $\mathcal{B}(η\to e^{\pm}μ^{\mp}) < 6.8 \times 10^{-7}$ at the 90\% confidence level. This result improves the previous best limit by one order of magnitude.

hep-ex↗

arXiv2026

First Experimental Constraint on the Scalar Current in the $D^{0(+)}\to \bar K\ell^+ν_{\ell}$ Transition

Using 20.3 fb$^{-1}$ of $e^+e^-$ collision data taken at the center-of-mass energy of $\sqrt{s}=3.773$ GeV, we report the first experimental constraint on the scalar current in the $D^{0(+)}\to \bar K\ell^+ν_{\ell}$ transitions, based on a simultaneous fit to the first measured forward-backward asymmetries and precisely determined partial decay rates. The parameters of the scalar current are determined to be ${\rm Re}(c_S^μ)=0.017\pm0.008_{\rm stat}\pm0.006_{\rm syst}$ and ${\rm Im}(c_S^μ)=\pm(0.077\pm0.011_{\rm stat}\pm0.009_{\rm syst})$, which deviates from the SM by a significance of $2.3σ$. The branching fractions of $D^{0(+)}\to \bar K\ell^+ν_\ell$, the hadronic form factor $f_+(0)$, and the modulus of the $c\to s$ CKM matrix element $|V_{cs}|$ are also determined with improved precision. In addition, lepton flavor universality is tested via the ratios of the decay rates between semi-muonic and semi-electronic decays in the full momentum transfer range and in subranges.

hep-ex↗

arXiv2026

Precise measurements of $D^0 \to K^-\ell^+ν_\ell$ and $D^+ \to \bar K^0\ell^+ν_\ell$ decays

Using $e^+e^-$ collision data corresponding to an integrated luminosity of 20.3 fb$^{-1}$, collected at the center-of-mass energy of 3.773 GeV with the BESIII detector, we present precise measurements of $D^0 \to K^-\ell^+ν_\ell$ and $D^+ \to \bar K^0\ell^+ν_\ell$ ($\ell=e,μ$) decays. The branching fractions of $D^0\to K^-e^+ν_e$, $D^0\to K^-μ^+ν_μ$, $D^+\to \bar K^0e^+ν_e$, and $D^+\to \bar K^0μ^+ν_μ$ are measured to be $(3.548\pm0.006_{\rm stat}\pm0.017_{\rm syst}) \%$, $(3.445\pm0.007_{\rm stat}\pm0.017_{\rm syst}) \%$, $(8.928\pm0.025_{\rm stat}\pm0.050_{\rm syst}) \%$, and $(8.770\pm0.029_{\rm stat}\pm0.053_{\rm syst}) \%$, respectively. The partial decay rates of these four decays are measured with improved precision, and their forward-backward asymmetries are determined for the first time. By performing a simultaneous fit to the measured partial decay rates and the forward-backward asymmetries of $D \to \bar K\ell^+ν_{\ell}$, a search for a possible scalar current contribution in the $c\to s\ell^+ν_{\ell}$ transition is performed. The results are ${\rm Re}(c_S^μ)=0.017\pm0.008_{\rm stat}\pm0.006_{\rm syst}$ and ${\rm Im}(c_S^μ)=\pm(0.077\pm0.011_{\rm stat}\pm0.009_{\rm syst})$, corresponding to a difference from the SM with a significance of $2.3σ$. The product of the form factor $f_+(0)$ and the modulus of the $c\to s$ Cabibbo-Kobayashi-Maskawa matrix element $|V_{cs}|$ is determined to be $f_+(0)|V_{cs}|=0.7183\pm0.0007_{\rm stat}\pm0.0014_{\rm syst}$. With the inputs $|V_{cs}|=0.97349\pm0.00016$ from the Standard Model global fit or $\ffK=0.7452\pm0.0031$ from the lattice quantum chromodynamics calculation, we derive $f_+(0)=0.7383\pm0.0007_{\rm stat}\pm0.0014_{\rm syst}$ and $|V_{cs}|=0.9639\pm0.0009_{\rm stat}\pm0.0018_{\rm syst}\pm0.0040_{\rm LQCD}$.

hep-ex↗

arXiv2026

Unexpected large relative strong phase and search for isospin breaking and $CP$ asymmetries in $J/ψ\to K^*(892)\bar K

Using a direct scan of 26 energy points near the $J/ψ$ resonance, we perform the first measurement of the relative phase $ϕ_{γ, 3g}$ between the strong and electromagnetic amplitudes in $J/ψ\to\bar K^0 K^*(892)^0+c.c.$ and $J/ψ\to K^+ K^*(892)^-+c.c.$. Unexpectedly, the phase in the neutral channel is found to be $\sim 150^\circ$, deviating from orthogonality ($90^\circ$) by 4.2$σ$ and from a relative real amplitude (0$^\circ$ or 180$^\circ$) by 10.0$σ$ or 1.6$σ$, respectively. In contrast, the charged channel phase is consistent with $\sim 180^\circ$ within 1$σ$, exhibiting model-dependent behavior. The corresponding branching fractions are consistent with the world averages but achieve better than twofold improvement in precision. The ratios between the branching fractions of $J/ψ\to\bar K^0 K^*(892)^0+c.c.$ and $J/ψ\to K^+ K^*(892)^-+c.c.$ are also measured. After subtracting the electromagnetic contribution, the corresponding strong amplitude ratios obey isospin symmetry within $1.8σ$. A search for direct $CP$ violation yields asymmetries consistent with zero.

hep-ex↗

arXiv2026

Strong and electromagnetic amplitudes, direct $CP$ and isospin asymmetries in the decays $J/ψ\to K^0_SK^+π^-+c.c.$

Using $e^+e^-$ annihilation data collected at 26 center-of-mass energy points between 3000.00 and $3119.88~\text{MeV}$ with the BESIII detector, corresponding to a total integrated luminosity of about $440.7~\text{pb}^{-1}$, we study the cross section lineshape of $e^+e^-\to K_S^0 K^+π^-+c.c.$. The relative phases and magnitudes between $J/ψ$ strong and electromagnetic decay amplitudes are measured to be $(123.7\pm5.3)^\circ;4.31\pm0.22$ or $(-123.1\pm5.2)^\circ;4.38\pm0.22$, with corresponding branching fractions $\mathcal{B}(J/ψ\to K_S^0 K^+π^-+c.c.)=(5.17\pm0.20)$ or $(5.36\pm0.20)\times10^{-3}$. Based on a partial wave analysis, the cross sections of $e^+e^-\to\bar K^0 K^*(892)^0+c.c.$ and $e^+e^-\to K^+ K^*(892)^-+c.c.$ are obtained. For these subprocesses, the relative phases and magnitudes are determined as $(155.2\pm15.5)^{\circ};3.67\pm0.27$ or $(-154.1\pm15.5)^{\circ};3.71\pm0.25$ and $(180.1\pm31.8)^{\circ};25.06\pm2.51$, respectively. The large relative phases deviate from the orthogonality relation expected from experiment and from the assumption of purely real amplitudes by more than $3σ$. The measured branching fractions $\mathcal{B}(J/ψ\to\bar K^0 K^*(892)^0)+c.c.=(4.18\pm0.18)$ or $(4.31\pm0.19)\times10^{-3}$, $\mathcal{B}(J/ψ\to K^+ K^*(892)^-+c.c.)=(7.09\pm0.28)\times10^{-3}$ are all consistent with the world average values, but achieve better than a twofold improvement in precision. The ratios between the branching fractions of $J/ψ\to\bar K^0 K^*(892)^0+c.c.$ and $J/ψ\to\bar K^+ K^*(892)^-+c.c.$ are $\mathcal{R}_{K^*\bar{K}}=0.589\pm0.012$ or $0.612\pm0.013$. After subtracting the electromagnetic contribution, the corresponding strong amplitude ratios are $\mathcal{R}^{3g}_{K^*\bar{K}}=0.884\pm0.050$ or $0.909\pm0.044$, which deviate $2.3$ or $2.1σ$ from the unity. No evidence for direct $CP$ violation is observed.

hep-ex↗

arXiv2026

Evidence of $ψ(3770) \to π^{0}J/ψ$

We report the first evidence for the hadronic transition $ψ(3770) \to π^0 J/ψ$ using a data sample of $20.3~\mathrm{fb}^{-1}$ collected at $\sqrt{s} = 3.773$~GeV with the BESIII detector. The $e^+ e^- \to π^{0}J/ψ$ process is observed with a statistical significance of $6.1σ$, while the significance specifically attributed to $ψ(3770) \to π^{0}J/ψ$ is $4.5σ$. We measure the dressed cross section for $e^+e^- \to π^0 J/ψ$ to be $(249 \pm 44 \pm 15)~\text{fb}$ and determine the branching fraction $\mathcal{B}(ψ(3770) \to π^0 J/ψ) = (2.08 \pm 0.36 \pm 0.21\pm 0.25) \times 10^{-5}$, where the first uncertainty is statistical, the second is systematic, and the third due to a possible interference with the $ψ(3686) \to π^{0}J/ψ$ decay. This is the first determination of this branching fraction. It lies significantly below tetraquark model predictions but aligns with calculations that incorporate meson loop effects, providing crucial insight into the isospin-violating nature of $ψ(3770)$ decays.

hep-ex↗

arXiv2026

Updated measurement of the branching fraction of $D_s^+ \to τ^+ ν_τ$

Using a dataset of 7.33 fb$^{-1}$ of $e^+ e^-$ annihilation data collected with the BESIII detector at center-of-mass energies from 4.128 to 4.226 GeV, we report an updated measurement of the branching fraction of $D_s^+ \to τ^+ ν_τ$ via four $τ^+$ decay modes: $τ^+ \to e^+ ν_e \barν_τ$, $μ^+ ν_μ \barν_τ$, $π^+\barν_τ$, and $π^+ π^{0} \barν_τ$. The branching fraction is determined to be $\mathcal{B}({D_s^+ \to τ^+ ν_τ}) = (5.37 \pm 0.08_{\rm stat} \pm 0.06_{\rm syst})$ %. The product of the modulus of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cs}|$ and the $D_s^+$ decay constant $f_{D_s^+}$ is measured to be $f_{D_s^+} |V_{cs}| = (248.2 \pm 1.9_{\rm stat} \pm 1.4_{\rm syst} \pm 0.6_{\rm input} \pm 0.8_{\rm EM})$ MeV. Both the branching fraction and the product $f_{D_s^+} |V_{cs}|$ are the most precise results yet obtained. Then, taking $f_{D_s^+}$ from lattice quantum chromodynamics calculations results in $|V_{cs}| = 0.993 \pm 0.008_{\rm stat} \pm 0.006_{\rm syst} \pm 0.003_{\rm input} \pm 0.003_{\rm EM}$. Conversely, one finds $f_{D_s^+} = (255.0 \pm 1.9_{\rm stat} \pm 1.4_{\rm syst} \pm 0.6_{\rm input} \pm 0.8_{\rm EM})$ MeV when taking $|V_{cs}|$ from the CKMfitter group as an input. Combining with the world average value of $D_s^+ \to μ^+ ν_μ$, the ratio of the branching fractions between $D_s^+ \to τ^+ ν_τ$ and $D_s^+ \to μ^+ ν_μ$ is estimated to be $10.04 \pm 0.29$, which is consistent with the Standard Model prediction of lepton flavor universality.

hep-ex↗

arXiv2026

Measurement of the branching fraction of $D_{s}^{*+}\to e^{+}e^{-}D_{s}^{+}$

The branching fraction of the electromagnetic Dalitz decay $D^{*+}_{s}\to e^{+}e^{-}D^{+}_{s}$ is measured with an $e^{+}e^{-}$ collision data sample collected by the BESIII experiment at center-of-mass energies between 4.128 and 4.226 $\mathrm{GeV}$, corresponding to a total integrated luminosity of 7.33 $\mathrm{fb}^{-1}$. The measurement yields the branching fraction ${\mathcal{B}(D^{*+}_{s}\to e^{+}e^{-}D^{+}_{s})=(7.28\pm0.61_{\mathrm{stat}}\pm0.31_{\mathrm{syst}})\times10^{-3}}$. The result is consistent with the previous one, with a 2.5-fold improvement in precision. This provides an important input for constraining the parameters of theoretical models and for determining the absolute branching fractions of $D^{*+}_{s}\to π^{0}D^{+}_{s}$ and $D^{*+}_{s}\to γD^{+}_{s}$, measured with a relative method.

hep-ex↗

arXiv2026

Search for the isospin-violating decays $\boldsymbol{χ_{cJ}\toΛ\barΣ^{0}+c.c.}$ and $\boldsymbol{η_{c}\toΛ\barΣ^{0}+c.c.}$

Using a sample of $(2712.4\pm14.3)\times10^{6}$~$ψ(3686)$ events collected with the BESIII detector, we perform a search for the isospin-violating decays $χ_{cJ}\toΛ\barΣ^{0}+c.c.~(J=0,1,2)$ and $η_{c}\toΛ\barΣ^{0}+c.c.$ No significant signal for $χ_{cJ}$ or $η_{c}$ is observed in the $Λ\barΣ^{0}$ invariant mass distribution. The upper limits on the branching fractions at the 90\% confidence level are set to be $\mathcal{B}$($χ_{c0}\toΛ\barΣ^{0}+c.c.$)$<1.5\times 10^{-6}$, $\mathcal{B}$($χ_{c1}\toΛ\barΣ^{0}+c.c.$)$<1.6\times 10^{-6}$, $\mathcal{B}$($χ_{c2}\toΛ\barΣ^{0}+c.c.$)$<1.7\times 10^{-6}$ and $\mathcal{B}$($η_{c}\toΛ\barΣ^{0}+c.c.$)$<6.2\times 10^{-5}$ for the first time.

hep-ex↗

arXiv2026

Search for the charmonium weak decay $ψ(2S)\to D_s^-π^+ + c.c.$ and $ψ(2S)\to D_s^-ρ^+ + c.c.$

We search for the weak decays $ψ(2S)\to D_s^-π^+ + c.c.$ and $ψ(2S)\to D_s^-ρ^+ + c.c.$ for the first time. The search is based on $(2712.4\pm14.3)\times 10^6$ events containing the charmonium state $ψ(2S)$ collected at the center-of-mass energy $\sqrt{s}=3.686\ \rm{GeV}$ with the BESIII detector. This search offers a unique opportunity to test the Standard Model and search for new physics. Since no signal excess above the background is observed, the upper limits on the branching fractions at the 90\% confidence level are set to be $1.4\times 10^{-6}$ and $7.0\times 10^{-6}$ for $ψ(2S)\to D_s^-π^+ + c.c.$ and $ψ(2S)\to D_s^-ρ^+ + c.c.$, respectively.

hep-ex↗

arXiv2026

Study of Central Exclusive Production of $π^+π^-$, $K^+K^-$ and $p \bar{p}$ Pairs in Proton-Proton Collisions at $\sqrt{s} = 510$ GeV with the STAR Detector at RHIC

We report on the first measurement of the Central Exclusive Production process in proton-proton collisions: $pp \ \rightarrow \ p h^+ h^- p$ (where $h = π, K, p$) at the center-of-mass energy $\sqrt{s} = 510$ GeV with the STAR experiment at RHIC. At this energy, the process is dominated by a double Pomeron exchange mechanism. Hence, it provides a clean environment for investigating Pomeron interactions by measuring fully reconstructed final states involving only two hadrons and two forward scattered protons. The oppositely charged hadron pairs are measured within the central detector of STAR. The forward scattered protons are measured in the Roman Pot system allowing the verification of the event's exclusivity. Differential fiducial cross sections within the STAR acceptance are presented as a function of the difference in the azimuthal angle between the outgoing protons. The invariant masses of the charged hadron pairs are measured up to approximately 3 GeV and the square of the four-momentum transfer ($t_1$ and $t_2$) of the two forward-scattered protons in the range $0.3 \text{ GeV}^2 < -t_1 , -t_2 < 1.6 \text{ GeV}^2$. The differential fiducial cross sections of the forward protons as a function of the $|t_1 + t_2|$ are also presented. All results for the $π^+π^-$ pair are presented in three mass ranges. A comparison with GRANIITTI Monte Carlo predictions are also presented, where the spectra include continuum and resonant contributions. The observed spectra are consistent with double Pomeron exchange, including resonances seen in previous studies.

hep-ex↗

arXiv2026

Measurement of Kaon Directed Flow in Au+Au Collisions in the High Baryon Density Region

Rapidity-odd directed flow $v_1$ measurements are presented for $K^{\pm}$ and $K^0_S$ in Au$+$Au collisions at $\sqrt{s_{\text{NN}}}$ = 3.0, 3.2, 3.5, and 3.9 GeV with the STAR experiment. For comparison, $v_1$ of $π^{\pm}$, protons, and $Λ$ from the same collisions are also discussed. The mid-rapidity $v_1$ slope $\text{d}v_1/\text{d}y|_{y=0}$ for protons and $Λ$ is positive in these collisions. On the other hand, $v_1$ slope of kaons exhibits a strong $p_\text{T}$ dependence: negative at $p_\text{T} <$ 0.6 GeV/$c$ and positive at higher $p_\text{T}$. A similar $p_\text{T}$ dependence is also evident for the $v_1$ slope of charged pions. Compared to the spectator-removed calculations in Au$+$Au collisions at $\sqrt{s_{\text{NN}}} =$ 3.0-3.9 GeV, the JAM model demonstrates a pronounced shift of the $v_1$ slopes of mesons towards the negative direction. It suggests that the shadowing effect of the spectators plays an important role in the observed kaon anti-flow at low $p_\text{T}$ in the high baryon density region of non-central collisions.

nucl-ex↗