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Observation of I (2S) →γηb (1S) Decay
Physical Review Letters. 2018. Vol. 121. No. 23. P. 1-8.
We report the observation of I(2S)→γηb(1S) decay based on an analysis of the inclusive photon spectrum of 24.7 fb-1 of e+e- collisions at the I(2S) center-of-mass energy collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We measure a branching fraction of B[I(2S)→γηb(1S)]=(6.1-0.7-0.6+0.6+0.9)×10-4 and derive an ηb(1S) mass of 9394.8-3.1-2.7+2.7+4.5 MeV/c2, where the uncertainties are statistical and systematic, respectively. The significance of our measurement is greater than 7 standard deviations, constituting the first observation of this decay mode. © 2018 authors. Published by the American Physical Society.
Caria G., Aushev T., Pakhlov P. et al., Physical Review Letters 2020 Vol. 124 No. 16 Article 161803
The experimental results on the ratios of branching fractions R(D)=B(B→Dτ-ντ)/B(B→Dℓ-νℓ) and R(D∗)=B(B→D∗τ-ντ)/B(B→D∗ℓ-νℓ), where ℓ denotes an electron or a muon, show a long-standing discrepancy with the standard model predictions, and might hint at a violation of lepton flavor universality. We report a new simultaneous measurement of R(D) and R(D∗), based on a data sample containing ...
Added: October 28, 2020
Katrenko P., Aushev T., Mizuk R. et al., Physical Review Letters 2020 Vol. 124 No. 12 Article 122001
We report the first observation of the radiative decay of the ψ(1S) into a charmonium state. The significance of the observed signal of ψ(1S)→γχc1 is 6.3 standard deviations including systematics. The branching fraction is calculated to be B[ψ(1S)→γχc1]=[4.7-1.8+2.4(stat)-0.5+0.4(sys)×10-5]. We also searched for ψ(1S) radiative decays into χc0,2 and ηc(1S,2S), and set upper limits on their ...
Added: October 28, 2020
Aushev T., Mizuk R., Pakhlov P. et al., Physical Review Letters 2018 Vol. 121 No. 3 P. 1-8
We report the results of a search for the rare, purely leptonic decay B-→μ-ν μ performed with a 711 fb-1 data sample that contains 772×106 BB pairs, collected near the (4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. The signal events are selected based on the presence of a high momentum ...
Added: October 28, 2020
Aushev T., Mizuk R., Pakhlov P. et al., Physical Review D - Particles, Fields, Gravitation and Cosmology 2018 Vol. 98 No. 11 P. 1-10
We report measurements of the branching fractions of the decays Λc+→Σ+π-π+, Λc+→Σ0π+π0 and Λc+→Σ+π0π0 relative to the reference channel Λc+→pK-π+. The analysis is based on the full data sample collected at and near the (4S) resonance by the Belle detector at the KEKB asymmetric-energy e+e- collider, corresponding to an integrated luminosity of 711 fb-1. We ...
Added: October 28, 2020
Pakhlov P., Попов В. Е., Journal of High Energy Physics 2020 Vol. 02 No. 160 P. 1-15
We propose a new method to extract D0−D¯0 mixing parameters using the D0→K¯0π0 decay with the K¯0 reconstructed in the semileptonic mode. Although a K0→π±l∓νl decay suffers from low statistics and complexity of the secondary vertex reconstruction in comparison to the standard KS→π+π− vertex, it provides much richer, sometimes unique information about the initial state ...
Added: November 16, 2020
Aushev T., Mizuk R., Pakhlov P. et al., Physical Review Letters 2020 P. 1-15
We report results from a study of the spin and parity of Ξc(2970)+ using a 980 fb−1 data sample collected by the Belle detector at the KEKB asymmetric-energy e+e− collider. The decay angle distributions in the chain Ξc(2970)+→Ξc(2645)0π+→Ξ+cπ−π+ are analyzed to determine the spin of this charmed-strange baryon. The angular distributions strongly favor the Ξc(2970)+ spin ...
Added: November 27, 2020
Aushev T., Mizuk R., Pakhlov P. et al., Physical Review D - Particles, Fields, Gravitation and Cosmology 2020 P. 1-14
We report the results of a first search for a doubly-charged DDK bound state, denoted the R++, in Υ(1S) and Υ(2S) inclusive decays and via direct production in e+e− collisions at s√ = 10.520, 10.580, and 10.867 GeV. The search uses data accumulated with the Belle detector at the KEKB asymmetric-energy e+e− collider. No significant ...
Added: November 27, 2020
Aushev T., Mizuk R., Pakhlov P. et al., Physical Review D - Particles, Fields, Gravitation and Cosmology 2020 P. 1-11
We report branching fraction measurements of four decay modes of the Λ+c baryon, each of which includes an η meson and a Λ baryon in the final state, and all of which are measured relative to the Λ+c→pK−pi+ decay mode.
The results are based on a 980 fb−1 data sample collected by the Belle detector at the ...
Added: November 27, 2020
Aushev T., Pakhlov P., Pakhlova G. et al., Physical Review Letters 2020 P. 1-17
We report the first evidence for X(3872) production in two-photon interactions by tagging either the electron or the position in the final state, exploring the highly virtual photon region. The search is performed in e+e−→e+e−J/ψπ+π−, using 825 fb−1 of data collected by the Belle detector operated at the KEKB e+e− collider. We observe three X(3872) ...
Added: November 27, 2020
EDP Sciences, 2021
The 25th International Conference on Computing in High Energy and Nuclear Physics (CHEP), organised by CERN, took place as a virtual event from 17–21 May 2021. The conference attracted 1144 registered participants from 46 different countries. There were 207 scientific presentations made over the 5 days of the conference. These were divided between 30 long ...
Added: September 14, 2021
Yelton J., Aushev T., Mizuk R. et al., Physical Review D - Particles, Fields, Gravitation and Cosmology 2020 Article 071103(R
Using 980 fb−1 of data collected with the Belle detector operating at the KEKB asymmetric-energy e^+e^- collider, we report a study of the electromagnetic decays of excited {charmed baryons} Ξc(2790) and Ξc(2815). A clear signal (8.6 standard deviations) is observed for Ξc(2815)0→Ξ0cγ, and we measure:
B[Ξc(2815)0→Ξ0cγ]/B[Ξc(2815)0→Ξc(2645)+π−→Ξ0cπ+π−]=0.41±0.05±0.03.
We also present evidence (3.8 standard deviations) for the similar decay ...
Added: November 27, 2020
Mizuk R., Aushev T., Pakhlov P. et al., Physical Review D - Particles, Fields, Gravitation and Cosmology 2020 P. 1-7
Using data collected in the Belle experiment at the KEKB asymmetric-energy e+e− collider we search for transitions Υ(4S)→ηb(1S)ω, Υ(5S)→ηb(1S)ω and Υ(5S)→ηb(2S)ω. No significant signals are observed and we set 90\% confidence level upper limits on the corresponding visible cross sections: 0.2 pb,0.4 pb and 1.9 pb, respectively. ...
Added: November 27, 2020
Ustyuzhanin A., Ratnikov F., Borisyak M. et al., Physical Review Letters 2019 Vol. 122 No. 22 P. 222001-1-222001-11
A narrow pentaquark state, Pc(4312)+, decaying to J/ψp, is discovered with a statistical significance of 7.3σ in a data sample of Λ0b→J/ψpK− decays, which is an order of magnitude larger than that previously analyzed by the LHCb Collaboration. The Pc(4450)+ pentaquark structure formerly reported by LHCb is confirmed and observed to consist of two narrow overlapping peaks, Pc(4440)+ and Pc(4457)+, where the statistical significance of this ...
Added: October 24, 2019
Abudinén F., Adachi I., Aushev T. et al., Physical Review Letters 2020 Vol. 125 No. 16 P. 1-9
We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e+e−→γa,a→γγ in the mass range 0.2<ma<9.7GeV/c2 using data corresponding to an integrated luminosity of (445±3)pb−1. Light pseudoscalars interacting predominantly with standard model gauge bosons ...
Added: November 27, 2020
Budkov Y., Kolesnikov A. L., Polymer Science - Series C 2018 Vol. 60 No. Supplement 1 P. 148-159
Theoretical models of the conformational behavior of flexible polymer chains in mixed solvents enunciated in the world literature during the last decade are critically reviewed. Models describing different mechanisms of coil-to-globule transitions in a good solvent induced by cosolvent addition are highlighted. Special attention is given to the analysis of theoretical approaches to describing the ...
Added: November 30, 2018
Казанцев Д. В., Казанцева Е. А., Кузнецов Е. В. et al., Известия РАН. Серия физическая 2017 Т. 81 № 12 С. 1709-1714
Описаны принципы работы безапертурного сканирующего микроскопа ближнего оптического поля (ASNOM). Зондом в приборе служит металлизированная игла атомно-силового микроскопа, и оптическое взаимодействие с объектами на поверхности локализовано вблизи ее острия размером в несколько нанометров. Тело иглы имеет длину в несколько микрон, и это обеспечивает высокую эффективность ее электромагнитного взаимодействия с падающими на нее извне и излучаемыми ...
Added: December 6, 2020
Antipov A., Seleznev V., Vakhtomin Y. et al., IOP Conference Series: Materials Science and Engineering (MSE) 2020 Vol. 781 No. 1 P. 012011-1-012011-5
Spectral characteristics of WSi and NbN superconducting single-photon detectors with different surface resistance and width of nanowire strips have been investigated in the wavelength range of 1.3-2.5 µm. WSi structures with narrower strips demonstrated better performance for detection of single photons in longer wavelength range. The difference in normalized photon count rate for such structures ...
Added: December 10, 2020
M. : Faculty of Physics, MSU, 2017
The Low Temperature Physics Conference is an international event held every three years, under the auspices of the IUPAP through its Commission C5 on Low Temperature Physics. The aim of these conferences is to exchange information and views among the members of the international scientific community in the general field of Low Temperature Physics. It ...
Added: October 1, 2017
Mikheev A. V., Вестник Санкт-Петербургского университета. Серия 1. Математика. Механика. Астрономия 2007 № 2 С. 128-133
In this work we consider the task of stability of shallow orthotropic shell on elastic base. The dependence of critical load parameter on constants of shell’s elasticity and rigidity of base is considered. As example we analyse the case of spherical shell made of unidirectional glass-fiber material. ...
Added: January 31, 2013
Boldyrev K., Романов А., Хаула Е. et al., Journal of the American Ceramic Society 2019 Vol. 102 No. 5 P. 2745-2751
Single crystal of TlCl was doped with NIR photoluminescent univalent bismuth cations by prolonged immersion in liquid bismuth metal. The ion exchange Tl+ + Bi0 ↔ Tl0 + Bi+ at the crystal surface with subsequent Bi+ migration to the bulk are expected to drive the doping process. Contrary with Bi‐doped TlCl crystals, grown by Bridgman method, the ion exchange does ...
Added: February 8, 2019
Kalmykov A., Melentiev P., Balykin V., Laser Physics Letters 2020 Vol. 17 No. 4 P. 045901
In this paper we present measurements and comparison of SPP propagation length at the practically important telecom wavelength (1560 nm) as well as in the near-infrared and visible spectral ranges. The measurements were carried out for plane SPP waves excited on Ag film surface using optical microscopy of SPP waves in the far field. We ...
Added: January 15, 2021
Dziom V., Shuvaev A. V., Shchepetilnikov A. et al., Physical Review B: Condensed Matter and Materials Physics 2019 Vol. 99 No. 4 Article 045305
The integer quantum Hall effect is a well-studied phenomenon at frequencies below about 100 Hz. The plateaus in high-frequency Hall conductivity were experimentally proven to retain up to 33 GHz, but the behavior at higher frequencies has remained largely unexplored. Using continuous-wave terahertz spectroscopy, the complex Hall conductivity of GaAs/AlGaAs heterojunctions was studied in the ...
Added: December 11, 2020
Kuzmichev S. A., Kuzmicheva T. E., Tchesnokov S. N. et al., Journal of Superconductivity and Novel Magnetism 2016 Vol. 29 No. 4 P. 1111-1116
We present temperature dependences of the large and the small superconducting gaps measured directly by SnS-Andreev spectroscopy in various Fe-based superconductors and MgB2. The experimental L,S(T ) are wellfitted with a two-gap model based on Moskalenko and Suhl system of equations (supplemented with a BCS integral renormalization). From the fitting procedure, we estimate the key ...
Added: March 19, 2016
Aaij R., Abdelmotteleb A. S., Abellán Beteta C. et al., Physical Review Letters 2022 Vol. 129 No. 9 Article 091801
The first study of the angular distribution of μþμ− pairs produced in the forward rapidity region via the Drell-Yan reaction pp → γ=Z þ X → lþl− þ X is presented, using data collected with the LHCb detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.1 fb−1. The coefficients ...
Added: December 29, 2022