13.24 Highlights of What’s New in Version 34.1.0, 27 February 2018

Here is a summary of what’s changed since release 34.0. Historical change logs are collected in Section 13.

13.24.1 Bug Fixes for Elements

• Restored the long-deprecated DIRECTION parameter for the SCRAPER element, as a convenience.
• Fixed a problem that caused the SCRIPT element to sometimes hang up in Pelegant if some processors did not have any particles after loading data from the script output file.
• The UKICKMAP element would sometimes fail to add synchrotron radiation effects during tracking even if asked; this would happen, for example, if there was no twiss_output or matrix_output command.
• The WIGGLER, UKICKMAP, CWIGGLER, and GFWIGGLER elements had an inconsistency in radiation integral computations, in that in some cases gamma was used when βγ was intended. The differences were very small for any practical case.
• The BRAT element and the abrat commandline program for tracking particles through 3D field distributions had an error in the initial coordinate transformation, discovered by R. Lindberg (APS). In practical use, the error seems to have had a negligible effect on results. Also, the element was treated as a drift for matrix computations; now, the matrix is determined by tracking (which can be time-consuming).
• Synchrotron radiation calculations for KQUAD, KSEXT, and KOCT had a bug that resulted in only the last component being computed. For example, if steering or higher multipoles were included, those would override the effect of the main field.
• Previously, when the KQUAD element was split (with the divide_elements command or element_divisions in the run_setup command), soft-edge effects would be replicated at the interior boundaries. This was fixed.
• Soft-edge effects on the KQUAD element were not exactly symmetric. This would, e.g., introduce a slight asymmetry into an otherwise symmetric lattice. This has been fixed.

13.24.2 Bug Fixes for Commands

• The rf_setup command could not handle α_c < 0, as discovered using files provided by P. Piot (NIU/FNAL). This was fixed.
• The analyze_map command would crash if SDDS output was not requested. This was fixed.

13.24.3 New and Modified Elements

• The CCBEND element, which integrates symplectically in Cartesian coordinates through a straight-pole combined-function bending magnet, was added.
• The BMXYZ element, which integrates particles through straight-element 3D magnetic field maps, now includes misalignment parameters. Multiple BMXYZ elements that use the same field map will share the data internally to reduce I/O and memory requirements.
• The EHKICK, EVKICK, and EHVKICK elements now include the RANDOM_MULTIPOLE_FACTOR and SYSTEMATIC_MULTIPOLE_FACTOR parameters.
• The BGGEXP element can now handle bending magnets. The non-symplectic integrator was replaced with a new method that is more accurate. R. Lindberg (APS) did most of the work on this.

13.24.4 New and Modified Commands

• During tracking, particles are no long checked against apertures after transitioning through zero-length elements that don’t modify the aperture. This improves performance in lattices with many MONI, MARK, and similar elements.
• The analyze_map command can now output the matrix in SDDS format to second or third order, on request.

13.24.5 Changes Specific to the GPU Version

The GPU version continues to be an alpha release and contains bugs. Users are encouraged to check results against the serial or parallel versions and report issues to the developers.

• None.

13.24.6 Changes to Related Programs and Files

• The program sddsbrightness now correctly includes the effect of J_x and J_y on the x and y emittances when the -coupling option is used.
• Added the script parmela2elegant, to convert PARMELA beam data (ASCII format) to a form acceptable by elegant.
• Fixed error in the atomic mass of CO₂ in the script ionTrapping.