A unique 1–3 Fast Processes station is proposed as part of the first-stage experimental stations at the SKIF Center for Shared Use, which is designed for studying the detonation and shock wave processes, as well as the material response to pulsed thermal or mechanical impacts. The station includes three sections: Plasma section, designed to study the processes of materials response to pulsed thermal and mechanical loading, Dynamic processes I section (main building), which is supposed to study the shock wave processes, and Dynamic processes II (separate building), intended for studying the detonation and shock wave processes. To conduct the experiments at 1–3 stations, five coordinate X‑ray detectors of various types are being developed. Their characteristics and current status are described in detail.

Представлена разработка многоканальной специализированной интегральной микросхемы (ASIC) для регистрации и обработки сигналов с микрополосковых сенсоров в координатных детекторах синхротронного излучения, разрабатываемых в ИЯФ СО РАН для оснащения экспериментальных станций ЦКП СКИФ. Микросхема содержит 64 независимых канала регистрации фотонов с 4 порогами разделения по энергиям. Диапазон регистрируемых энергий составляет от 3 до 60 кэВ. Подробно описана структура и основные параметры электроники канала регистрации для прямого счёта фотонов. The development of a multichannel application-specific integrated circuit (ASIC) for registration and processing of signals from microstrip sensors in synchrotron radiation coordinate detectors developed at the Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences to equip the experimental stations of the SKIF is presented. The ASIC contains 64 independent photon registration channels with four energy separation thresholds. The range of registered energies is from 3 to 60 keV. The structure and basic parameters of the electronics of the registration channel for direct photon counting are described in detail.

The article is devoted to the development of new control electronics for semiconductor one-coordinate X-ray detectors for the Synchrotron Radiation Facility SKIF. The developed electronics are designed to work in one-coordinate detectors of photon counting (SciCODE) and integrating (DIMEX-Si) types. Electronics’ tasks include controlling the specialized integrated circuits operation on the front-end board, processing experimental data, and presenting the results through user interface software. The control electronics include a field programmable gate array (FPGA) for generating control signals for connected devices and processing experimental results, static memory blocks for storing experimental results, and an Ethernet data transfer interface to the user’s computer. Appropriate FPGA designs and software are being developed for the operation of electronics with front-end boards for a photon counting or integrating mode detector. The article discusses the design of control electronics, its firmware and software. This development will be applied also in the design of a two-coordinate semiconductor X-ray detector.

The e^+e^-→ηγ cross section is measured in the center-of-mass energy range from 1.07 to 2.00 GeV in the decay channel η→ 3π^0 , π^0→γγ . The data set with an integrated luminosity of 242 pb ^-1 accumulated in the experiment with the SND detector at the VEPP-2000 e^+e^- collider is analyzed.

The process e^+e^-→π^+π^-π^0 was studied in the energy range between 1.075 and 1.975 GeV on the basis of data characterized by an integrated luminosity of about 70 pb ^-1 that were accumulated in an experiment with the Spherical Neutral Detector (SND) at the VEPP-2000 e^+e^- collider. The respective Dalitz distributions were analyzed within a model that includes ρ(770)π , ρ(1450)π , and ωπ^0 intermediate states. As a result, the energy dependences of the total cross section for the process e^+e^-→π^+π^-π^0 and the cross sections for the ρ(770)π and ρ(1450)π intermediate states were measured along with the phase shift of the ρ(770)π amplitude with respect to the ρ(1450)π and ωπ^0 amplitudes. For the first time, a simultaneous approximation of the cross sections for the processes e^+e^-→ρ(770)π and ρ(1450)π and the relative phase of the respective final states was performed on the basis of the vector-meson dominance model. The contributions of the ω , ϕ , ω(1420) , and ω(1650) resonances were taken into account. The approximation showed that the decay ω(1650)→π^+π^-π^0 proceeds predominantly through the ρ(1450)π intermediate state, while the decay ω(1420)→π^+π^-π^0 receives a dominant contribution from the ρ(770)π mechanism. The results of this study refined the results of earlier measurements with the SND setup.

A multichannel application specific integrated circuit (ASIC) for registration and processing of signals from microstrip sensors in synchrotron radiation coordinate detectors developed at the BINP SB RAS to equip the SKIF experimental stations is presented. The ASIC contains 64 independent photon registration channels with 4 energy separation thresholds. The range of registered energies is from 3 to 60 keV. The structure and main parameters of the registration channel electronics for direct photon counting are described in detail.

— The review presents the experiments performed with the KEDR detector at the e^ + e^ - collider VEPP-4M in the energy range of √(s) = 1.84–3.88 GeV. The cross section of e^ + e^ - annihilation to hadrons was measured at 22 points of this range and the search for narrow resonances was conducted below 3.1 GeV. The masses of J / . -0emψ and ψ (2S) mesons were measured with a record accuracy better than 3 ×10^ - 6 ; their partial and total widths were determined. Measurements of the tau lepton mass and masses of charged and neutral D mesons were performed with high precision. The measurements of the ψ (3770) parameters are discussed, and attention is drawn to some inconsistency of the procedure employed by the Particle Data Group for determining its parameters.

The process e+e−→ωπ0→π+π−π0π0 is studied in the center-of-mass energy region 1.05–2.00 GeV using data with an integral luminosity of about 35 pb−1 collected with the SND detector at the VEPP-2000 e+e− collider. In the energy range under study, the value of the measured Born cross section varies from 0.7 to 18 nb. The statistical uncertainty of the cross section is 2%–23%, while the systematic uncertainty is in the range of 3.0%–14.2%. The results are consistent with previous measurements but have better accuracy.4 MoreReceived 6 September 2023Accepted 1 November 2023DOI:https://doi.org/10.1103/PhysRevD.108.092012Published 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.Published by the American Physical SocietyPhysics Subject Headings (PhySH)Research AreasHadron productionLepton-lepton interactionsPhysical SystemsLight mesonsPropertiesForm factorsParticles & Fields

Abstract We report the measurement of the two-photon decay width of χc2(1P) in two-photon processes at the Belle experiment. We analyze the process γγ → χc2(1P) → J/ψγ, J/ψ → ℓ+ℓ− (ℓ = e or μ) using a data sample of 971 fb−1 collected with the Belle detector at the KEKB e+e− collider. In this analysis, the product of the two-photon decay width of χc2(1P) and the branching fraction is determined to be $$ {\Gamma}_{\gamma \gamma}\left({\chi}_{c2}(1P)\right)\mathcal{B}\left({\chi}_{c2}(1P)\to J/\psi \gamma \right)\mathcal{B}\left(J/\psi \to {\ell}^{+}{\ell}^{-}\right)=14.8\pm 0.3\left(\textrm{stat}.\right)\pm 0.7\left(\textrm{syst}.\right) $$ Γ γγ χ c 2 1 P B χ c 2 1 P → J / ψγ B J / ψ → ℓ + ℓ − = 14.8 ± 0.3 stat . ± 0.7 syst . eV, which corresponds to Γγγ(χc2(1P)) = 653 ± 13(stat.) ± 31(syst.) ± 17(B.R.) eV, where the third uncertainty is from $$ \mathcal{B} $$ B (χc2(1P) → J/ψγ) and $$ \mathcal{B} $$ B (J/ψ → ℓ+ℓ−).

The e+e− → ηγ cross section is measured in the center-of-mass energy range from 1.07 to 2.00 GeV in the decay channel η → 3π0, π0 → γγ. The data set with an integrated luminosity of 242 pb−1accumulated in the experiment with the SND detector at the VEPP-2000 e+e− collider is analyzed.

In experiment at the VEPP-2000 e(+)e(-) collider the process e(+)e(-) -> n (n) over bar has been studied in the energy from the threshold up to 2 GeV. To identify n (n) over bar events the multichannel NaI(Tl) electromagnetic calorimeter of the SND detector was used. The measured e(+)e(-) -> n (n) over bar process cross section is from 0.6 to 0.3 nb. The effective neutron timelike form factor is derived and compared with the proton form factor. The ratio | G(E)|/|G(M)| of the neutron electric and magnetic form factor is obtained from the measured angular distribution and found to be between 1 and 2.

We present the study of the decay J/ψ → ρπ . The results are based on of 5.2 million J/ψ events collected by the KEDR detector at the VEPP-4M collider. The branching fractions are measured to be ℬ ( J/ψ → ρπ ) = (2 . 072 ± 0 . 017 ± 0 . 062) ∙ 10 − 2 and ℬ ( J/ψ → π + π − π 0 ) = (1 . 878 ± 0 . 013 ± 0 . 051) ∙ 10 − 2 , where the first uncertainties are statistical and the second systematic. Our results are more precise than the previous relative measurements.

The work describes a one-dimensional detector for diffraction experiments at a synchrotron radiation beam. The detector is being developed at the Budker Institute of Nuclear Physics, Siberian Branch, Russian Academy of Sciences. Until recently the institute was developing gas one-coordinate detectors, in particular a one-coordinate detector with calculated channels (OD-3M), based on the technology of multiwire proportional chambers. To provide a spatial resolution better than 100 microns at a photon energy in a wide energy range (3–30 keV), it is necessary to use solid-state microstrip or matrix sensors in combination with specialized integrated registration circuits. The developed SOCOD detector, using a microstrip sensor based on gallium arsenide as a registration element, operates in the mode of the direct counting of photons with an energy of more than 3–4 keV and a speed of up to 1 MHz/channel. The work gives a general description of the current version of the detector, a block diagram of the registration channel, the software allowing users to control the operation of the detector and display the results obtained, and the developed algorithm for leveling the trigger thresholds in the channels. The results of electronic tests, the work of the alignment algorithm and their discussion are presented.

We present a search for the decay X(3872)→π+π−π0 in the (772±11)×106 Υ(4S)→B¯B data sample collected at the Belle detector, where the X(3872) is produced in B±→K±X(3872) and B0→K0SX(3872) decays. We do not observe a signal, and set 90% credible upper limits for two different models of the decay processes: if the decay products are distributed uniformly in phase space, B(X(3872)→π+π−π0)<1.3%, and if M(π+π−) is concentrated near the mass of the D0¯D0 pair in the process X(3872)→D0¯D*0+c.c.→D0¯D0π0→π+π−π0, B(X(3872)→π+π−π0)<1.2×10−3.Received 17 June 2022Accepted 26 September 2022DOI:https://doi.org/10.1103/PhysRevD.107.052004Published 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.Published by the American Physical SocietyPhysics Subject Headings (PhySH)Research AreasBranching fractionHadronic decaysQuantum chromodynamicsQuark modelStrong interactionParticles & Fields

X-ray one-coordinate detectors of photon counting and integrating types based on semiconductor microstrip sensors are developed in the Budker Institute of Nuclear Physics (BINP SB RAS) for the dynamic experiments at the synchrotron radiation facility SKIF. The photon counting detector SciCODE register signal from each photon absorbed in the detector sensitive volume and exceeding the set threshold. In integrating detector DIMEX-Si, the total signal from a large flux of photons that hit the detector in a short frame time is registered. To achieve a spatial resolution of better than 100 µm in a wide range of photon energies and high output data rate a specialized integrated circuits are necessary for signal detection and recording. Based on the results of the development and testing of prototypes of integrated circuits for counting and integrating detectors, full-scale ASICs SciCODE64 for counting and DMXS64A for integrating detectors were developed. Both ASICs contain 64 independent registration channels. SciCODE64 allows to work with a range of recorded energies from 3 to 40 keV at a rate up to 1 MHz. DMXS64A is designed to reach dynamic range of about 1000, maximum photon flux of 10 5 photons per frame (30 keV) and frame rate of 50 MHz.

The super τ-charm facility (STCF) is an electron–positron collider proposed by the Chinese particle physics community. It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5 × 1035 cm−2·s−1 or higher. The STCF will produce a data sample about a factor of 100 larger than that of the present τ-charm factory — the BEPCII, providing a unique platform for exploring the asymmetry of matter-antimatter (charge-parity violation), in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions, as well as searching for exotic hadrons and physics beyond the Standard Model. The STCF project in China is under development with an extensive R D program. This document presents the physics opportunities at the STCF, describes conceptual designs of the STCF detector system, and discusses future plans for detector R D and physics case studies.

We present a measurement of the $B^{0} \rightarrow D^{*-} \ell^{+} \nu_{\ell}$ ($\ell=e,\mu$) branching ratio and of the CKM parameter $|V_{cb}|$ using signal decays accompanied by a fully reconstructed $B$ meson. The Belle II data set of electron-positron collisions at the $\Upsilon(4S)$ resonance, corresponding to 189.3$\,$fb$^{-1}$ of integrated luminosity, is analyzed. With the Caprini-Lellouch-Neubert form factor parameterization, the parameters $\eta_{\rm EW} F(1) |V_{cb}|$ and $\rho^{2}$ are extracted, where $\eta_{\rm EW}$ is an electroweak correction, $F(1)$ is a normalization factor and $\rho^{2}$ is a form factor shape parameter. We reconstruct 516 signal decays and thereby obtain $\mathcal{B} (B^{0} \rightarrow D^{*-} \ell^{+} \nu_{\ell} ) = \left(5.27 \pm 0.22~\rm{\left(stat\right)} \pm 0.38~\rm{\left(syst\right)}\right) \%$, $\eta_{EW} F(1) |V_{cb}| \times 10^{3} = 34.6 \pm 1.8~\rm{\left(stat\right)} \pm 1.7~\rm{\left(syst\right)}$, and $\rho^{2} = 0.94 \pm 0.18~\rm{\left(stat\right)} \pm 0.11~\rm{\left(syst\right)}$.