Application of software and hardware components of CAN-technology for accelerator control

CAN-technology was developed for embedded hard real time automotive applications. CAN-bus together with high-level application protocols is used now to control large experimental installations and particle accelerators. CAN-technology includes fieldbus, universal and specialized controllers, sensors and actuators. Software components of CAN-technology consist of high level application protocols, programs for testing, monitoring and configuring of CAN-nodes as well as the components which bind CAN-components with SCADA systems and ensure control through the WEB-browsers. CAN-technology is used in INP to control accelerators, for beam diagnostic and, in cooperation with the RRC Kurchatov Institute, in automation of the large neutrino detector Borexino. CAN-bus adapters for PC have been constructed. Such software components as drivers for PC adapters, the bus emulator and protocol analyzers have been developed under Linux. Original specialized high level protocols have been developed for closed specialized systems. Source codes have been developed and verified for compatibility with international standards such as DeviceNet and CANopen for use in the systems that are supposed to be extended with commercially available software and hardware components. Long-term positive experience of CAN-technology usage allows us to recommend this technology for accelerator control especially if industrial style and compatibility is desired.CAN технологія була розроблена для застосування як убудовану мережу жорсткого реального часу для автоелектроніки. У НІДЯФ МГУ технологія CAN застосовується для контролю і керування прискорювачами, діагностики пучка і, разом із РНЦ Курчатовський Інститут, для автоматизації великого нейтринного детектора Borexino. Багаторічний позитивний досвід роботи з CAN і експлуатація систем керування з CAN дозволяє рекомендувати цю технологію для побудови систем керування прискорювачами.CAN технология была разработана для применения в качестве встроенной сети жесткого реального времени для автоэлектроники. В НИИЯФ МГУ технология CAN применяется для контроля и управления ускорителями, диагностики пучка и, совместно с РНЦ Курчатовский Институт, для автоматизации большого нейтринного детектора Borexino. Многолетний позитивный опыт работы с CAN и эксплуатация систем управления с CAN позволяют рекомендовать эту технологию для построения систем управления ускорителями

Neutrino-induced deuteron disintegration experiment

Cross sections for the disintegration of the deuteron via neutral-current (NCD) and charged-current (CCD) interactions with reactor antineutrinos are measured to be 6.08 +/- 0.77 x 10^(-45) cm-sq and 9.83 +/- 2.04 x 10^(-45) cm-sq per neutrino, respectively, in excellent agreement with current calculations. Since the experimental NCD value depends upon the CCD value, if we use the theoretical value for the CCD reaction, we obtain the improved value of 5.98 +/- 0.54 x 10^(-45) for the NCD cross section. The neutral-current reaction allows a unique measurement of the isovector-axial vector coupling constant in the hadronic weak interaction (beta). In the standard model, this constant is predicted to be exactly 1, independent of the Weinberg angle. We measure a value of beta^2 = 1.01 +/- 0.16. Using the above improved value for the NCD cross section, beta^2 becomes 0.99 +/- 0.10.Comment: 22pages, 9 figure

Initial Results from the CHOOZ Long Baseline Reactor Neutrino Oscillation Experiment

Initial results are presented from CHOOZ, a long-baseline reactor-neutrino vacuum-oscillation experiment. Electron antineutrinos were detected by a liquid scintillation calorimeter located at a distance of about 1 km. The detector was constructed in a tunnel protected from cosmic rays by a 300 MWE rock overburden. This massive shielding strongly reduced potentially troublesome backgrounds due to cosmic-ray muons, leading to a background rate of about one event per day, more than an order of magnitude smaller than the observed neutrino signal. From the statistical agreement between detected and expected neutrino event rates, we find (at 90% confidence level) no evidence for neutrino oscillations in the electron antineutrino disappearance mode for the parameter region given approximately by deltam**2 > 0.9 10**(-3) eV**2 for maximum mixing and (sin(2 theta)**2) > 0.18 for large deltam**2.Comment: 13 pages, Latex, submitted to Physics Letters

Search for neutrino oscillations on a long base-line at the CHOOZ nuclear power station

This final article about the CHOOZ experiment presents a complete description of the electron antineutrino source and detector, the calibration methods and stability checks, the event reconstruction procedures and the Monte Carlo simulation. The data analysis, systematic effects and the methods used to reach our conclusions are fully discussed. Some new remarks are presented on the deduction of the confidence limits and on the correct treatment of systematic errors.Comment: 41 pages, 59 figures, Latex file, accepted for publication by Eur.Phys.J.

Limits on Neutrino Oscillations from the CHOOZ Experiment

We present new results based on the entire CHOOZ data sample. We find (at 90% confidence level) no evidence for neutrino oscillations in the anti_nue disappearance mode, for the parameter region given by approximately Delta m**2 > 7 x 10**-4 eV^2 for maximum mixing, and sin**2(2 theta) = 0.10 for large Delta m**2. Lower sensitivity results, based only on the comparison of the positron spectra from the two different-distance nuclear reactors, are also presented; these are independent of the absolute normalization of the anti_nue flux, the cross section, the number of target protons and the detector efficiencies.Comment: 19 pages, 11 figures, Latex fil

Search for Solar Axions Produced in p(d,3He)Ap(d,\rm{^3He})A Reaction with Borexino Detector

A search for 5.5-MeV solar axions produced in the $p+d\rightarrow\rm{^3He}+A (5.5 \rm{MeV})$ reaction was performed using the Borexino detector. The Compton conversion of axions to photons, ${\rm A}+e\rightarrow e+\gamma$; the axio-electric effect, ${\rm A}+e+Z\rightarrow e+Z$; the decay of axions into two photons, ${\rm A}\rightarrow2\gamma$; and inverse Primakoff conversion on nuclei, ${\rm A}+Z\rightarrow\gamma+Z$, are considered. Model independent limits on axion-electron ($g_{Ae}$), axion-photon ($g_{A\gamma}$), and isovector axion-nucleon ($g_{3AN}$) couplings are obtained: $|g_{Ae}\times g_{3AN}| \leq 5.5\times 10^{-13}$ and $|g_{A\gamma}\times g_{3AN}| \leq 4.6\times 10^{-11} \rm{GeV}^{-1}$ at $m_A <$ 1 MeV (90% c.l.). These limits are 2-4 orders of magnitude stronger than those obtained in previous laboratory-based experiments using nuclear reactors and accelerators.Comment: 11 pages, 7 figures, submitted to Phys.Rev.