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Machine Parameters
Table 4 presents a summary of the characteristics of the electron beam of the storage ring.
Table 4: Main global parameters of the electron beam. |
Table 5 gives the main optics functions, electron beam sizes and divergences, at the various source points. For insertion device source points, the beta functions, dispersion, sizes and divergences are computed in the middle of the straight section. Two representative source points of bending magnet radiation have been selected corresponding to an angle of observation of 3 mrad (9 mrad) from the exit, they correspond to different fields. Electron beam profiles are Gaussian and the size and divergence are presented in terms of rms quantities. The associated fwhm sizes and divergences are 2.35 larger. Beam sizes and divergences are given for the uniform filling modes and apply to almost all filling patterns, except the single bunch for which a slightly larger size and divergence is reached due to the increased energy spread of the electron beam.
Table 5: Beta functions, dispersion, rms beam sizes and divergences for the various source points. |
The lifetime, bunch length and energy spread depend on the filling pattern. They are given in Table 6 for a few representative filling patterns. Note that in both the 16 bunch and single bunch modes, the energy spread and bunch length decay with the current, the value indicated in the table corresponding to the maximum current. The bunch lengths are given for the usual RF accelerating voltage of 8 MV.
Table 6: Current, lifetime, bunch length and energy spread in various representative filling modes. |