119479887
S-D mixing and ψ (3770) production in e + e − annihilation and B decay and its radiative transitions
The large decay rate observed by Belle for ${B}^{+}\ensuremath{\rightarrow}\ensuremath{\psi}(3770){K}^{+}$, which is comparable to ${B}^{+}\ensuremath{\rightarrow}\ensuremath{\psi}(3686){K}^{+}$, might indicate either an unexpectedly large S-D mixing angle $|\ensuremath{\theta}|\ensuremath{\approx}{40}^{\ifmmode^\circ\else\textdegree\fi{}}$ or the leading role of the color-octet mechanism in D-wave charmonium production in $B$ decay. By calculating the production rate of $\ensuremath{\psi}(3770)$ in the continuum ${e}^{+}{e}^{\ensuremath{-}}$ annihilation at $\sqrt{s}=10.6\text{ }\text{ }\mathrm{G}\mathrm{e}\mathrm{V}$ with these two possible approaches (i.e., the large S-D mixing and the color-octet mechanism), we show that the measurement for this process at Belle and BABAR may provide a clear cut clarification for the two approaches. In addition, the radiative E1 transition ratio $\ensuremath{\Gamma}[\ensuremath{\psi}(3770)\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\chi}}_{c2}]/\ensuremath{\Gamma}[\ensuremath{\psi}(3770)\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\chi}}_{c1}]$ may dramatically change from $\ensuremath{\sim}$ 0.04 (for $\ensuremath{\theta}\ensuremath{\approx}{0}^{\ifmmode^\circ\else\textdegree\fi{}}$) to $\ensuremath{\sim}200$ (for $\ensuremath{\theta}\ensuremath{\approx}\ensuremath{-}{40}^{\ifmmode^\circ\else\textdegree\fi{}}$) due to the large S-D interference effect, thus the E1 transition measurement of $\ensuremath{\psi}(3770)$ at Beijing Spectrometer and CLEO-c will also be very useful in clarifying this issue.
124097178
Neutrino Oscillation and CP Violation in Low Energy Phenomenology of an SUSY Model
Neutrino oscillation and CP violation effects are discussed in an SUSY model proposed in Ref. [1]. The oscillation probabilities expected by this model in short baseline and long baseline neutrino oscillation experiments are calculated. The small conversion probability is predicted for all or oscillations. However, large long baseline oscillation probability is predicted, which could be observed in future long baseline experiments.
41516045
Earth leakage problem of superconductor magnet system at TLS
Due to the inherent connection structure between the power supplies and the superconducting magnetic coil, the power supplies are seeing each others as loads through the coil. It has been observed in the pilot test at TLS that there is about 300 mA Earth leakage current flowing through the earth leakage protection circuit, which presented an interlock and halted the whole system down. The existence of Earth leakage current may undermine the overall system stability and pose more threat on the electronic system safety. In this paper, the Earth leakage mechanisms are thoroughly examined and measures to conquer the problem are proposed.
164614043
Analysis and Compensator Design of Magnet Correction Power Supply
POWER SUPPLY Yong-Seng Wong , Kuo-Bin Liu, Jhao-Cyuan Huang NSRRC, Hsinchu 30076, Taiwan . Abstract This paper presents a new method for the analysis and design of compensators for magnet correction (MC) power supply. The system has to need controllers to satisfy required gain and phase margin specifications and compensator by adding to circuit controller and switch. The gain-phase margin tester method can transform of the controller and find solutions on the figure. According to circuit frequency response and transfer function by theory analysis and simulation design new method compensators to improved anti-disturbance and stability of the system.
54875662
Power factor simulation of focus quadrupole DC power supply of white circuit system with MATLAB simulink
The focus quadrupole DC power supply used at white circuit system of booster ring of Synchrotron Radiation Research Center (SRRC) is a 19.2kW unit, but an AC power source to measure the power factor of such a power supply with built-in power factor measuring function is very expensive. Power factor simulation of this power supply with MATLAB Simulink software is economic and the simulated results may be used to find some efficient ways to correct this parameter if necessary. The results from the simulation model will be compared with the results of power factor monitored from direct measurement on AC mains. The model of quadrupole DC power supply is constructed and provided for better understanding for further modification.
120411181
Recent progress in techniques utilized for particle accelerator
Particle accelerators are widely used in scientific research and industry. Recently, techniques utilized for accelerator are developed rapidly in China. We briefly review the recent progress in this field and primarily focus on superconducting RF, innovative structures for particle production and acceleration and beam diagnosis. Several advanced compact user facilities are also introduced.
55506316
The Design and Fabrication of the Kicker Power Supply for TPS Project
The preliminary test results of the kicker power supply for TPS (Taiwan Photon Source) project will be presented in this report. The achieved capability of this test unit demonstrates that it fulfills the design requirement of providing half-sine pulsed current of 2.5 kA (peak), 5.2 μs (base-width), with jitter < 1 ns (peak-to-peak). Both units of using thyratron and IGBT switches are built with the same requirements. The technical considerations of both units for this particular application will be discussed. INTRODUCTION The Taiwan Photon Source (TPS) under construction consists of a 150 MeV electron linac, a 3 GeV full energy booster, and a 3 GeV storage ring. The storage ring is planned to operate top-up at 400 mA. The top-up filling process will take place periodically within about every 100 seconds. In order to fulfill this requirement, the injection kickers will be triggered repeatedly at the same repetition rate. This proposed topup operation mode requires stringent performance of the 4 injection kickers for good stability on pulse amplitude and jitter, and in particular, pulse-shape matching among these 4 kickers. Test units of the kicker pulser have been built to examine their feasibility. Pulsers using both thyratron and IGBT switches have been tested. The results show that both units fulfill the pulser requirements on amplitude and jitter stability. The system configuration and the test results are briefly described in this report. PERFORMANCE REQUIREMENTS The circumference of the TPS storage ring is 518.4 m [1]. Beam injection will be taken place at a 10 m long straight section. The proposed injection scheme demand a 5.2 μs (base-width) half-sine pulse for the injection kickers in order to perform four-turn injection process [2]. The estimated parameters had been applied to examine and evaluate the feasibility of building pulse power supply for kicker in house. The design of the prototype kicker magnet requires the driving peak current to be 2.5 kA. The suggested stability goals of both pulse amplitude and jitter for the test unit are given as 0.5% and 2 ns, respectively. Since top-up mode will be implemented in the future for routine user operation, performance on high reliability and small long term drift of the test unit are required. The stability will be examined and analyzed for this purpose. The estimated parameters for evaluating kicker pulser test unit are given in Table 1. Table 1: Parameters for evaluating kicker pulser test unit straight section (m) 10 magnet length (m) 0.6