Search for CP violation in Xi_c+ -> Sigma+ h+ h- and Lambda

?

Search for CP violation in Xi_c+ -> Sigma+ h+ h- and Lambda_c+ -> p h+ h- at Belle II

Physical Review Letters. 2026. Vol. D. No. 113. Article 032017.

Bodrov D., Pakhlova G., Abumusabh М.

We report decay-rate CP asymmetries of the singly-Cabibbo-suppressed decays Xi_c+ -> Sigma+ h+ h- and Lambda_c+ -> p h+ h-, with h=K, pi, measured using 428 fb^-1 of e+ e- collisions collected by the Belle II experiment at the SuperKEKB collider. The results, ACP(Xi_c+ -> Sigma+ K+ K-) = (3.7 +/- 6.6 +/- 0.6)%, ACP(Xi_c+ -> Sigma+ pi+ pi-) = (9.5 +/- 6.8 +/- 0.5)%, ACP(Lambda_c+ -> p K+ K-) = (3.9 +/- 1.7 +/- 0.7)%, ACP(Lambda_c+ -> p pi+ pi-) = (0.3 +/- 1.0 +/- 0.2)%, where the first uncertainties are statistical and the second systematic, agree with CP symmetry. From these results we derive the sums ACP(Xi_c+ -> Sigma+ pi+ pi-) + ACP(Lambda_c+ -> p K+ K-) = (13.4 +/- 7.0 +/- 0.9)%, ACP(Xi_c+ -> Sigma+ K+ K-) + ACP(Lambda_c+ -> p pi+ pi-) = (4.0 +/- 6.6 +/- 0.7)%, which are consistent with the U-spin symmetry prediction of zero. These are the first measurements of CP asymmetries for individual hadronic three-body charmed-baryon decays.

Research target: Physics

Language: English

Full text

DOI

Publication based on the results of:

Search for New physics in the experiments on e+e- colliders (2025)

Study of B+ -> mu+ nu_mu decays at Belle and Belle II

Pakhlov P., Pakhlova G., Bodrov D. et al., Physical Review Letters 2026 Vol. D No. 113 Article 112012

We report a measurement of the branching fraction for the leptonic decay B+ -> mu+ nu_mu. This work presents the first B+ -> mu+ nu_mu result using Belle II data, an updated Belle measurement that supersedes the previous result, and their combination, which yields the most precise search to date. The analysis is based on ...

Added: October 2, 2026

A quantum–analogue formalism for modeling supraliminal information processing

Lubashevsky I., Lubashevskiy V., Physica D: Nonlinear Phenomena 2026 Vol. 498 Article 135441

We develop a novel cloud-function formalism describing the dynamical relationship between sensory-information processing in large-scale brain networks (supraliminal processing) and the content of the mental representation of an observed object. The formalism combines elements of neural field theory for large-scale neural activity with the spatial characteristics of perceived objects and their embedding in the environment ...

Added: October 2, 2026

Search for the Decay B+ -> K+ tau+ tau- Using Data from the Belle and Belle II Experiments

Bodrov D., Pakhlov P., Pakhlova G. et al., Physical Review Letters 2026 Vol. 137 Article 051805

We report a search for the rare decay B+ -> K+ tau+ tau- using 1.2 x 10^9 Upsilon(4S) mesons produced near threshold in electron-positron collisions and collected by the Belle and Belle II experiments. We fully reconstruct the hadronic decay of one B meson produced in the Upsilon(4S) -> B+ B- decay, and search for ...

Added: October 1, 2026

Observation of the Radiative Decay D*_s0(2317)+ -> D*+_s gamma

Bodrov D., Aushev Т., Abumusabh М., Physical Review A: Atomic, Molecular, and Optical physics 2026 No. 136 Article 241901

We report the first observation of the radiative decay D*_s0(2317)+ -> D*+_s gamma with a statistical significance exceeding 10 standard deviations. The signal is observed in the continuum e+ e- -> c c-bar process, using combined data samples of 980.4 fb^-1 from Belle and 427.9 fb^-1 from Belle II, collected at the KEKB and SuperKEKB ...

Added: October 1, 2026

First measurements of the branching fractions for the decay modes Ξ0𝑐 →Λ⁢𝜂 and Ξ0𝑐 →Λ⁢𝜂′ and search for the decay Ξ0𝑐 →Λ⁢𝜋0 using Belle and Belle II data

Bodrov D., Pakhlova G., Aushev Т. et al., Physical Review A: Atomic, Molecular, and Optical physics 2026 Vol. D 113 Article 032015

Using data samples of 988.4 fb^-1 and 427.9 fb^-1 collected with the Belle and Belle II detectors, we present a study of the singly Cabibbo-suppressed decays Xi0_c -> Lambda eta, Lambda eta', and Lambda pi0. We observe the decay Xi0_c -> Lambda eta and find evidence for the decay Xi0_c -> Lambda eta', with corresponding ...

Added: October 1, 2026

Study of e+e− → π +π −Υ(1D) at Belle II

Pakhlov P., Pakhlova G., Bodrov D. et al., Journal of High Energy Physics 2026 Article 278

The bottomonium spectrum, consisting of bound states of a b quark and an anti-b quark, provides an excellent laboratory for probing quantum chromodynamics in the non-perturbative regime. While S and P-wave bottomonium states are well studied experimentally, information on D-wave states remains scarce. We search for the D-wave bottomonium states Upsilon_2(1D) and Upsilon_3(1D) via the ...

Added: October 1, 2026

Measurement of time-dependent CP violation parameters in B 0 → KS0π 0γ decays at Belle and Belle II

Bodrov D., Pakhlova G., Uglov T. et al., Journal of High Energy Physics 2026 Vol. 09 No. 216

We perform a measurement of time-dependent CP violation parameters in B0 -> KS0 pi0 gamma decays using a dataset of approximately 772 x 10^6 and 521 x 10^6 Upsilon(4S) decays collected by the Belle and Belle II experiments, respectively. The measured parameters for the combined dataset in the K0(892) dominated region (M_KS0pi0 in [0.8, 1.0] ...

Added: October 1, 2026

Searches for Charged-Lepton-Flavor Violation in χbJð1PÞ Decays

Pakhlov P., Pakhlova G., Bodrov D. et al., Physical Review Letters 2026 No. 137 Article 071803

We report the first searches for charged-lepton-flavor violation in decays of chi_bJ(1P) (J = 0, 1, and 2) to a pair of charged leptons using 158 million Y(2S) decays collected with the Belle detector in e+ e- collisions at the KEKB collider. No significant signal is observed, and we set upper limits on the branching ...

Added: October 1, 2026

Markovian reduction and exponential mixing in total variation for random dynamical systems

Kuksin S., Shirikyan A., Journal of Dynamics and Differential Equations 2026 P. 1098–1100

The paper deals with the problem of large-time behaviour of trajectories for discrete-time dynamical systems driven by a random noise. Assuming that the phase space is finite-dimensional and compact, and the noise is a Markov process with a transition probability satisfying some regularity hypotheses, we prove that all the trajectories converge to a unique measure ...

Added: October 1, 2026

Asymptotics of Spectrum and Quantum Averages of the Hydrogen Atom in a Magnetic Field Near the Upper Boundaries of Spectral Clusters

A. V. Pereskokov, Journal of Mathematical Sciences 2026 Vol. 302 No. 4 P. 531–545

We consider the Zeeman effect problem for the hydrogen atom in a magnetic field using irreducible representations of the Karasev–Novikova algebra with quadratic commutation relations. We find the asymptotics of a series of eigenvalues and the corresponding asymptotic eigenfunctions near the upper boundaries of spectral clusters. ...

Added: October 1, 2026

Small area quantum-dot stripe lasers with focused-ion-beam-etched mirrors

Obraztsova Anna, Fominykh Nikita, Komarov Sergey et al., Applied Physics Letters 2026 Vol. 129 Article 132110

Miniaturization of edge-emitting quantum-dot lasers is hampered by increased mirror losses in ultra-short Fabry–Perot cavities and limited modal gain of quantum dots (QDs). Here, we demonstrate electrically injected InGaAs/GaAs quantum-dot stripe lasers with an 8-lm stripe width and focused-ion-beam (FIB)-etched mirrors defining cavity lengths from 300 to 77 lm. The laser cavities were fabricated using ...

Added: September 30, 2026

Нетривиальное поведение пирамидальных уединенных волн в обобщенном уравнении Гарднера

Melnikov I., Pelinovsky E., Доклады Российской академии наук. Физика, технические науки (ранее - Доклады Академии Наук. Физика) 2026 Т. 529 С. 29–36

Conditions for the emergence of pyramidal solitary waves (solitary waves possessing more than two inflection points) are presented for a family of generalized Korteweg – de Vries (KdV) equations. For the generalized Gardner equation, it is shown that pyramidal solitons are unstable. The decay of initial perturbations close to pyramidal solitary waves is demonstrated numerically. ...

Added: September 29, 2026

Benchmarking exchangecorrelation functionals and van der Waals treatments for materials relevant to diamond-like carbon deposition

Kartsev A., Васильев Д. А., Kushchuk L. et al., Materials Today Communications 2026

Amorphous carbon coatings, including diamond-like carbon (DLC), exhibit a wide range of structural and mechanical properties governed by the local bonding topology (the sp2/sp3 ratio), as well as by deposition conditions and substrate material. Recently, machine-learning interatomic potentials trained predominantly on density functional theory (DFT) reference data have significantly advanced multiscale modeling of amorphous carbon ...

Added: September 28, 2026

The Search of the Process e+e−→(ω, ρ)→ηe+e− at 680–820 MeV c.m. Energy Range with the CMD-3 Detector

A. K. Narvatkina, Physics of Atomic Nuclei 2025 Vol. 88 No. 4 P. 386–393

We report a search for the rare Dalitz decays ω → ηe+e− and ρ → ηe+e− using data from the CMD-3 detector at the VEPP-2000 e+e− collider. These decays probe the electromagnetic structure of vector mesons and test the Vector Dominance Model (VDM) in low-energy QCD. A blind analysis technique, combined with kinematic constraints and ...

Added: September 28, 2026

Polaron transport and Verwey transition in magnetite

Fominykh N., Stegailov V., Physical Review B: Condensed Matter and Materials Physics 2026 Vol. 114 Article 115132

The enigmatic puzzle of the Verwey transition in magnetite Fe3O4 has been unresolved for almost a century. We present an ab initio-based model of the polaron transport combining kinetic Monte Carlo and molecular dynamics calculations to directly describe the coupling of polarons with lattice vibrations. Contrary to the Ihle-Lorenz small-polaron model, we find no significant ...

Added: September 28, 2026

Role of dislocations in the mobility of pinned helium bubbles: Molecular dynamics simulations in aluminum

Piliugin L., Antropov A., Lobashev E. et al., Journal of Nuclear Materials 2026 Vol. 632 Article 156876

The effects of dislocations on the mobility of gas nanobubbles pinned to them are considered as novel unex- plored mechanisms of accelerated fission gas release and investigated using classical molecular dynamics of helium bubbles in FCC aluminum. Non-equilibrium methods are developed to calculate the mobility of a pinned bubble both along and across the dislocation ...

Added: September 28, 2026

A Three-Party W-State Quantum Secret Sharing Protocol with X-Gate Encoding and Forbidden-Outcome Detection

Teregulov T., Loubenets E. R., / Series Quantum Physics "arXiv". 2026. No. 2609.31472.

We develop a new three-party quantum secret-sharing (QSS) protocol based on a three-qubit W state. This protocol encodes the secret-sequence bits using X gates and employs randomly selected Hadamard operations and measurement bases to generate information and security-test rounds. We evaluate the efficiency of the proposed protocol and analyze its security against an internal adversary ...

Added: September 28, 2026

Constructing quasi-breathers in 𝛽-FPUT chain with the aid of genetic algorithm

Щербинин С. А., Корзникова Е. А., Дмитриев С. В. et al., Physics Letters A 2026 Vol. 591 Article 131884

In this work, a simple genetic algorithm (GA) is used to find and characterize different QBs in a 𝛽-FPUT chain. By considering the space of initial particle displacements as a global optimization landscape, GA maximizes the energy localization function by automatically evolving candidate states toward highly localized long-lived solutions without a priori symmetry assumptions. 200 ...

Added: September 28, 2026

Speed-up of Langmuir instability at large scales when the wave scattering is significant

Vergeles S. S., Vointsev I., Physics of Fluids 2026 Vol. 38 P. 024117-1–024117-8

We analytically consider the problem of the Langmuir instability. The instability describes emergence of transverse modulation of horizontal current with vertical shear, when it is superimposed on surface wave co-directional with the flow. Compared to the Craik–Leibovich scheme, we account for the scattering of surface wave on the modulated current, which is significant if the ...

Added: September 26, 2026

Surface acoustic wave enabled all-optical determination of the interlayer elastic constants of a van der Waals interface

Frolov N. Y., Klokov A. Y., Sharkov A. I. et al., Applied Physics Letters 2026 Vol. 128 P. 092201-1–092201-5

Understanding the properties of two-dimensional material interfaces with the substrate is necessary for device applications. Surface acoustic wave propagation through a layered material flake on a substrate could provide unique information on the transverse rigidity of the flake-to-substrate interaction. Ultrasonic waves were generated by a focused femtosecond laser pulse at the surface of a model ...

Added: September 26, 2026

InGaAsN/GaAs quantum-well-based microlasers improved by PECVD SiO2 passivation

Войтович В. И., Makhov I., Мельниченко И. А. et al., Optics Letters 2026 Vol. 51 No. 17 P. 4872–4875

The influence of cavity surface passivation with SiO2 coating deposited by the plasma-enhanced chemical vapor deposition technique is investigated for injection microdisk lasers with an InGaAsN/GaAs quantum well active region. The electroluminescence spectra of the microdisk lasers with cavity diameters ranging from 12 to 32 μm with and without sidewall surface passivation were studied for a ...

Added: September 25, 2026

Микролазеры с распределенными брэгговскими отражателями Al0.2Ga0.8As/Al0.9Ga0.1As

Бабичев А. В., Makhov I., Kryzhanovskaya N. et al., Оптика и спектроскопия 2026 Т. 134 № 3 С. 272–277

Представлены результаты по реализации генерации при повышенных температурах в лазерах с длиной волны генерации 980 nm на основе вертикального микрорезонатора с использованием непоглощающих на длине волны оптической накачки зеркал. Минимальная пороговая мощность накачки составила ~0.8 mW и соответствовала температуре 150 K. Добротность микрорезонатора, определенная на пороге генерации, превысила 13000. Максимальная рабочая температура микролазера составила 195 ...

Added: September 25, 2026

Design and Commissioning of Readout Electronics for a K L 0 and μ Detector at the Belle II Experiment

Ketter C., Andrew M., Aushev T. et al., Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 2026 Vol. 1082 No. P.

The K-long and muon detector (KLM) constitutes the outer-most volume of the Belle II spectrometer at the interaction region of the SuperKEKB collider in Tsukuba, Japan. The KLM detector was partially upgraded since the Belle experiment by replacing many of its resistive-plate chambers with scintillators containing wavelength-shifting fibers and instrumenting it with silicon photomultipliers. We describe the readout ...

Added: September 15, 2025

Measurement of the integrated luminosity of the Phase 2 data of the Belle II experiment

Abudinén F., Aushev T., Mizuk R. et al., Chinese Physics C 2020 Vol. 44 No. 2 Article 021001

From April to July 2018, a data sample at the peak energy of the γ(4S) resonance was collected with the Belle II detector at the SuperKEKB electron-positron collider. This is the first data sample of the Belle II experiment. Using Bhabha and digamma events, we measure the integrated luminosity of the data sample to be ...

Added: October 28, 2020