Highlights of What’s New in Version 2020.5

Here is a summary of what’s changed since release 2020.4. Historical change logs are collected in Section 16.

The SCATTER element had a bug in the implementation of the ENDONPASS parameter, which was being ignored if the value was 0.
The CCBEND element had several misalignment-related issues. Most significantly, the ETILT parameter was ignored. In addition, the sense of DX and DY was inverted when when the ANGLE was negative. As a result of these fixes, misalignment effects from CCBEND will change. Setting ETILT=0 and DX_DY_SIGN=-1 will cause the code to revert to the old behavior.

Frequency map analysis would crash in some circumstances when there was a CHARGE in the beamline. This bug was reported by G. Penn (LBNL).

The BGGEXP element now supports both normal and skew components. R. Lindberg (APS) implemented the symplectic integrator option for this.
The BMAPXYZ element now has a FSE (Fractional Strength Error) parameter.
The RADIAL_ORDER parameter of RFTMEZ0 can now be set to 0 to turn off radial dependence of fields.
The POLYSERIES element was released, which allows transforming the beam using a set of arbitrary polynomials in the canonical coordinates. This existed in the code but was not documented. It was developed by L. Emery (APS) and inspired by work of Y. P. Sun (APS).
The ETILT_SIGN parameter for CSBEND, CSRCSBEND, RBEN, and SBEN now defaults to 1. The previous default of -1, for backward compatibility, was potentially confusing.

Added the change_start command, which permits changing the starting location in a lattice. This was inspired by a request from Duan Zhe (IHEP).
The obstruction_data command now supports multiple vertical planes of data.

The computeRBGGE program was added, allowing computation of a generalized gradient expansion[50] for use with BGGEXP based on field data on a rectangular boundary [57]. The code was developed by R. Lindberg (APS) with help from R. Soliday (APS) and M. Borland (APS).