JPS6484177A - Beam position monitor for electron storage ring - Google Patents

Abstract

PURPOSE:To improve the accuracy of beam position detection by employing spherical electrodes as at least a couple of electrodes. CONSTITUTION:The cross section of the vacuum tank 1 for the electron storage ring is elliptic and spherical electrodes 2 are installed above and below an x=0 position and on the right and left sides of a y=0 position. Further, a feed through 3 for leading out an output voltage is penetrated to the vacuum tank wall at an electrode installation place and soldered to electrodes in the tank. Consequently, the stray electrostatic capacity between the electrodes 2 and vacuum tank wall can be reduced to about 1/2 at the time of a circular electrode, and the output voltage of each electrode 2 is increased and the output voltages from respective electrodes 2 rise, so that the ratio of (x)- and (y)- directional output voltages and the sensitivity function are improved. Thus, the spherical electrodes are used and then a component fitted to the vacuum tank wall is only the feed through 3 for leading out the output voltage, so the electrodes 2 can be installed at (x)- directional and (y) directional long- diameter position as the maximum sensitivity position, i.e. possible position at the longest distance.