Improvements and Bug Fixes for Elements

• Added fiducialization to MATR element to resolve problems with matrices that have nonzero $R_{n5}$ or $T_{n5m}$ elements. This bug was found by Paul Emma (SLAC).
• The SREFFECTS element (which does synchrotron radiation effects in tracking) had several bug fixes.
  • Fixed problems with quantum excitation when the element was placed in a region with high dispersion.
  • Fixed problems with quantum excitation when the of FRACTION parameter was used.
• Fixed bugs and added features to IBSCATTER (intrabeam scattering):
  • Added SMOOTH parameter to allow selecting a nonrandom simulation of IBS (simply does inflation of the emittances according to the growth factor).
  • Added FACTOR parameter to allow multiplying IBS effects by a chosen factor.
  • Fixed problem with energy scattering that caused false exponential growth in energy spread for low-energy beams.
• Fixed problem with tlimit implementation for CLEAN element that caused incorrect results for low-energy beams.
• In prior versions, when tracking a circular machine with CSR in bends and drifts, the first CSR drift would not be handled properly. This has been fixed.
• Added LINEARIZE control for CSRCSBEND and CSRDRIFT, which allows using purely linear transport between CSR wake kicks.
• Added low-pass filter capability for CSRCSBEND element. This allows applying a low-pass filter to the density histogram, as a form of noise control. The filter is also applied to the CSRDRIFT elements downstream of each CSRCSBEND element.
• Added renormalization of density histograms after smoothing and filtering in CSRCSBEND and CSRDRIFT. This enforces conservation of charge and prevents negative values of the particle density.
• Added LINEARIZE control for RFCA and RFCW, which results in a linear dependence of energy gain on phase deviation.