This paper describes an approach enabling the continuous monitoring of all devices on the Synchrotron Radiation Facility Siberian Circular Photon Source (SRF SKIF) accelerator complex units ...synchronically with the measurements of beam parameters. The operation of devices is monitored in distributed controllers with a frequency of 10 kHz. After detecting any deviations from specified parameters above the tolerance value in the operation of a device, the controller of this device sets a corresponding signal. When a beam exhibits an abnormal behavior, the comparative analysis of synchronous data from the distributed controllers and the beam diagnosing electronics is performed to reveal the device resulting in such a behavior.
The VEPP-5 Injection complex provides BINP colliders with electron and positron beams. In order to supply the beams in a continuous mode, the control system infrastructure needs to be highly ...available. It is proposed to implement this infrastructure using modern virtualization technologies. The design and implementation of the VEPP-5 injection complex control system infrastructure is described.
Abstract
Using the 1.32
$$\hbox {pb}^{-1}$$
pb
-
1
statistics collected at the
$$J/\psi $$
J
/
ψ
peak with the KEDR detector at the VEPP-4M
$$e^{+}e^{-\, }$$
e
+
e
-
collider, we measured the ...branching fractions of
$$J/\psi $$
J
/
ψ
meson decays to the final states 2(
$$\pi ^{+}\pi ^{-})\pi ^{0}$$
π
+
π
-
)
π
0
,
$$K^{+}K^{-}\pi ^{+}\pi ^{-}\pi ^{0}$$
K
+
K
-
π
+
π
-
π
0
, 2(
$$\pi ^{+}\pi ^{-})$$
π
+
π
-
)
and
$$K^{+}K^{-}\pi ^{+}\pi ^{-}$$
K
+
K
-
π
+
π
-
. The results obtained for the decays
$$J/\psi \rightarrow $$
J
/
ψ
→
2(
$$\pi ^{+}\pi ^{-})\pi ^{0}$$
π
+
π
-
)
π
0
,
$$J/\psi \rightarrow K^{+}K^{-}\pi ^{+}\pi ^{-}\pi ^{0}$$
J
/
ψ
→
K
+
K
-
π
+
π
-
π
0
contradict the measurements performed by other groups in the last century, but agree well with recent results of BABAR and BESIII collaborations.
The mutual interconversion and decomposition reactions of four tetrazole isomers (1H-TZ, 2H-TZ, 5H-TZ, and an N-heterocyclic carbene 14H) have been studied theoretically using the W1 high-level ...procedure. Computations allowed resolution of the existing discrepancies in the mechanism and key intermediates of TZ thermolysis. The tautomeric equilibria between 1H-TZ, 2H-TZ, and 14H turned out to play a very important role in the mechanism of thermal decomposition. Although the barriers of monomolecular tautomeric transformations were found to be high (∼50−70 kcal/mol), the concerted double H atom transfer reactions in the H-bonded complexes of TZ tautomers have profoundly lower barriers (∼18−28 kcal/mol). These reactions lead to fast interconversion between 1H-TZ, 2H-TZ, and 14H. The carbene 14H has never been considered before; however, it was predicted to be a key intermediate in the mechanism of thermal decomposition of TZ. For all species considered, the unimolecular reactions of N2 elimination were predicted to dominate over the elimination of hydrazoic acid. In agreement with existing experimental data, the effective activation energy of thermolysis was calculated to be 36.2 kcal/mol.
—
The review presents the experiments performed with the KEDR detector at the
collider VEPP-4M in the energy range of
= 1.84–3.88 GeV. The cross section of
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
and
mesons were measured with a record accuracy better than
; their partial and total widths were determined. Measurements of the tau lepton mass and masses of charged and neutral
mesons were performed with high precision. The measurements of the
parameters are discussed, and attention is drawn to some inconsistency of the procedure employed by the Particle Data Group for determining its parameters.
Abstract Using the 1.32 $$\hbox {pb}^{-1}$$ pb - 1 statistics collected at the $$J/\psi $$ J / ψ peak with the KEDR detector at the VEPP-4M $$e^{+}e^{-\, }$$ e + e - collider, we measured the ...branching fractions of $$J/\psi $$ J / ψ meson decays to the final states 2( $$\pi ^{+}\pi ^{-})\pi ^{0}$$ π + π - ) π 0 , $$K^{+}K^{-}\pi ^{+}\pi ^{-}\pi ^{0}$$ K + K - π + π - π 0 , 2( $$\pi ^{+}\pi ^{-})$$ π + π - ) and $$K^{+}K^{-}\pi ^{+}\pi ^{-}$$ K + K - π + π - . The results obtained for the decays $$J/\psi \rightarrow $$ J / ψ → 2( $$\pi ^{+}\pi ^{-})\pi ^{0}$$ π + π - ) π 0 , $$J/\psi \rightarrow K^{+}K^{-}\pi ^{+}\pi ^{-}\pi ^{0}$$ J / ψ → K + K - π + π - π 0 contradict the measurements performed by other groups in the last century, but agree well with recent results of BABAR and BESIII collaborations.
A method for monitoring electron synchrotron parameters is proposed. The adjustment and control of the synchrotron are analyzed. The architecture, operation logic, and software means of the ...monitoring system are considered. The software of the monitoring system of the booster parameters for the NSLS-II synchrotron light source is described, which was developed on the basis of the EPICS software environment.
We present the study of the decay \(J/\psi \rightarrow \rho\pi\). The results are based on of 5.2~million \(J/\psi\) events collected by the KEDR detector at the VEPP-4M collider. The branching ...fractions are measured to be \(\B(J/\psi \rightarrow \rho\pi) = \big(2.072\pm 0.017 \pm 0.062 \big)\cdot 10^{-2}\) and \(\B(J/\psi \rightarrow \pi^+\pi^-\pi^0) = \big(1.878 \pm 0.013 \pm 0.051 \big)\cdot 10^{-2}\), where the first uncertainties are statistical and the second systematic. Our results are more precise than the previous relative measurements.
The present work continues a series of the KEDR measurements of the \(R\) value that started in 2010 at the VEPP-4M \(e^+e^-\) collider. By combining new data with our previous results in this energy ...range we measured the values of \(R_{\text{uds}}\) and \(R\) at nine center-of-mass energies between 3.08 and 3.72 GeV. The total accuracy is about or better than \(2.6\%\) at most of energy points with a systematic uncertainty of about \(1.9\%\). Together with the previous precise \(R\) measurement at KEDR in the energy range 1.84-3.05 GeV, it constitutes the most detailed high-precision \(R\) measurement near the charmonium production threshold.
