PyECLOUD Version 7.3.1

Added two minor features:

• Script to save the electron density movie
• Test for StrongBdip tracking

PyECLOUD Version 7.3.0

New feature (towards multi-bunch instability simulations):

• Buildup can be simulated with non-uniform time step (provided by non-uniform sampling in the beam profile specified by the user).
• An additional test case has been added and existing tests have been modified in order to check this feature.

PyECLOUD Version 7.2.0

Code restructuring as part of the multi-bunch instability simulation development. Main changes:

• PyEC4PyHT objects now include a full BuildupSimulation object (already with multiple clouds) which takes care of the cloud simulation. This allowed removing a lot of code duplication.
• Kick-drift mode introduced in the PyEC4PyHT class. This allows simulating fast-ion instabilities without using a specialised module. Therefore, the PyEC4PyHT_fastion module has been removed.
• pyecloud_saver module modified and restructured to be able to work without knowing a priori the length of the simulation. In the future this will have to be further adapted to work with non-uniform time-steps.
• Introduced test verifying all the buildup saving options (states, MP coordinates, optional histograms and diagnostics).

PyECLOUD Version 7.1.2

Minor changes:

• Compatibility with unicode strings (for multibunch PyPARIS simulations)
• Fix sign error in photoemission by segment (thanks Lotta!)
• Introduced test for photoemission by segment (thanks Lotta!)

PyECLOUD Version 7.1.1

Bug fix:

• Versions 7.0.0 and 7.1.0 were not working in PyPARIS mode (small initialization incompatibility). Fixed here.

PyECLOUD Version 7.1.0

New features:

• The area of the chamber is computed and stored.
• The orientation of polygonal chambers is checked (normal vectors should point inwards).

PyECLOUD Version 7.0.0

New feature:

• Buildup simulations can include multiple clouds made of different particle (electron/ion) species.

Thanks Lotta!

PyECLOUD Version 6.7.2

New features:

• SEY curves in a predefined energy interval and for selected angles are now included in the simulation output.
• Added example scripts to plot SEY curves from PyECLOUD input or output.
• The SEY dependence on the impacting angle is handled with the same interface in the ECLOUD model and when the SEY table is imported from file. Reference manual updated accordingly.
• "Angle 2D reference files" are removed.
• Introduced better path management for chamber and sey mat files.

PyECLOUD Version 6.7.1

Bugfix:

• Non-uniform SEY was not working since version 6.6.0. Fixed in this version.
• Added test simulation with non-uniform SEY.

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Internal changes:

• Added script to automatically change preamble (author list) in all source files.
• Renamed "sec_emission" module into "electron_emission" as it is now used also for photoemission.

Thanks to Philipp and Lotta!

PyECLOUD Version 6.7.0

New features:

• Possibility of specifying photoelectron distribution vs segment on a polygonal chamber.
• Removed default value for photoelectron_angle_distribution and secondary_angle_distribution (see below).

Thanks Philipp!

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Important: From this version the emission angle distribution must be specified, otherwise the simulation crashes!

To use the cosine_3D distribution (most appropriate) set in the machine parameter input file:
photoelectron_angle_distribution = 'cosine_3D'
and in the secondary emission input file:
secondary_angle_distribution = 'cosine_3D'

In case you want to use the cosine_2D distribution, to have the same behavior as in PyECLOUD 6.6.0 or earlier replace 'cosine_3D' with 'cosine_2D'. For more info, see presentation by P. Dijkstal on the angle of emission of generated electrons (https://indico.cern.ch/event/673160/).