New and Modified Commands

• Added the momentum_aperture command, which allows determination of the s-dependent momentum aperture. This work was inspired by requests from R. Bartolini (DLS) and F. Wang (MIT), as well as a discussion with L. Nadolski (SOLEIL).

• Added the aperture_input command, which allows specifying s-dependent aperture using an SDDS file. This was inspired by a discussion with R. Bartolini (DLS).

• Added computation of the coupling integral and emittance ratio (see section 3.1.4.4 of [18]). These are available for optimization using the symbols couplingIntegral and emittanceRatio. N.B.: this emittance ratio does not include the effect of vertical dispersion. This change was suggested by V. Sajaev (ANL).

• Added computation of coupled twiss parameters and beam sizes, using code supplied by V. Sajaev (ANL) based on [17]. This is done with the new coupled_twiss_output command. The command requires specifying the emittance ratio. While one might be tempted to use the value from the coupling integral (as in the previous item), we again note that this does not include vertical dispersion contributions.

• Added the match_name feature to the twiss_analysis command. For example, one can now compute and optimize on the average $\beta_x$ at elements with names matching a wildcard string.

• The default number of iterations for orbit correction (correct command) was increased to improve results for difficult (nearly unstable) cases. On a related note, if closed orbit computations are requested, they are now additionally performed prior to orbit correction in case orbit correction needs the perturbed correction matrix.

• Added the linear_chromatic_tracking_setup command, which allows tracking with a linear matrix representing a ring with defined chromatic variation of the tunes and lattice functions. This was previously only possible if the ring lattice was defined. The new feature allows tracking without defining the ring lattice. This was requested by S. Krinsky (BNL).