Xtrack version 0.10.1

Changes:

• Fix in import RF cavity from MAD-X when the harmonic number is provided.
• Fix in wire import from MAD-X.
• Example with Wakefield on CPU together with lattice tracking and spacecharge on GPU.
• Introduced test for mad import for several elements.
• Other minor fixes.

Xtrack version 0.10.0

Changes:

• Custom damping rate and equilibrium emittance in LinearTransferMatrix
• Tracker can transfer the particles to the CPU context for specific elements exposing .needs_cpu flag.
• Tracker can hide hidden particles for specific elements exposing .needs_hidden_lost_particles flag.
• Tracker in collective mode cleans pyheadtail slices (if present) for each line part.
• Spacecharge installation in line is now done in place.
• Introduced s_tol flag in Line.insert_element
• Fix bugs in Wire.to_dict, Elens.to_dict, DipoleEdge.to_dict.
• Introduced behaves_like_drift flag for thick elements (allows twiss inside the element)
• Fix in matrix responsiveness check in compute_linear_normal_form
• Regenerated all json files in test_data.

Xtrack version 0.9.5

Changes:

• Line.insert_element allows replacement of aperture elements.
• Introduced getitem capability for Line providing object associated to a given index or name.
• Thresholds for checking one-turn matrix validity can now be modified at runtime.
• Import of MAD-X sequence can handle repeated elements.
• More robust algorithm for closed-orbit search, exception raised if solution is not found.
• Faster algorithm for marker insertion in Tracker.twiss(at_s=...)
• Fix in introduction of multipole errors in the presence of deferred expressions.

Xtrack version 0.9.4

Fixes in Line.merge_consecutive_drift and Line.merge_consecutive_multipoles

Xtrack version 0.9.3

Fixes:

• MAD-X expressions referring to tables are now skipped
• Error in expression conversion for RFMultipole.lag

Xtrack version 0.9.2

New features:

• Introduced Wire beam element
• Line.insert_element(...) can insert a thin or think element at an arbitrary location s
• Tracker.twiss(...) can provide closed orbit, twiss parameters and phase advances at arbitrary s locations
• Tracker.track(...) can track particles from any element in the ring both in collective and non-collective modes. The element at which tracking starts is obtained from Particles.start_tracking_at_element if set.
• Introduced Line.get_s_position(...) method to get the longitudinal position of an element or a list of elements.

Xtrack version 0.9.1

Fixes:

• "ecollimator" element is recognised by the MAD-X loader.
• Additional mathematical functions can be used in expressions (e.g. sinc).

Xtrack version 0.9.0

Changes:

• Synchrotron radiation:
  • Corrected dependence on energy deviation in average and quantum modes.
  • Checked damping times and equilibrium emit against the emit module of MAD-X .
  • Added optional computation of damping times and energy loss in Tracker.twiss.
  • Synchrotron radiation modelling can be configured for the entire line using Line.configure_radiation(...).
  • Random number generator is automatically initialised by the tracker.track(particles) if radiation is activated through Line.configure_radiation(...) .
• Changed sign convention for cavity voltage if reference particle has negative charge.
• Added example and tests for CLIC Damping ring.
• Disabled automatic symplectification in Tracker.twiss (found to degrade accuracy on vertical dispersion).
• Tracker.twiss now returns additional data:
  • Scalars: T_rev, circumference, betz0.
  • Along the beam line: delta, psigma and zeta coordinates of the 6D closed orbit.
  • Optionally: damping_constants, partition_numbers and energy loss from radiation (see above).
• Tuned closed-orbit search algorithm. Info on numpy.fsolve convergence attached to returned particle object.
• Tracker.twiss checks that one-turn matrix is well defined
• Names of keyword arguments passed to beam element constructors are now checked (an exception is raised for unexpected names, e.g. typos).
• Tracker verifies that elements containing references to external data are allocated in the same buffer as the tracker.
• Fix in LossLocationRefinement (correct number of interpolated apertures).
• Simplified import of MAD-X expressions. Corrected management of expression in the presence of errors.
• Updated all examples.

Xtrack version 0.8.0

New features:

• Beam elements can be controlled with xdeps references.
• Deferred expressions controlling beam elements can be imported from MAD-X.
• Additional element properties are transferred to CPU when calling Element.to_dict()
• Change in internal data structure of xtrack.Line: elements are now stored in a dictionary mapping element names to element objects; the sequence of elements is defined by the list of element names. xtrack.Line.elements becomes a read-only property.

Fixes:

• Corrected chromaticity estimates for fractional tunes above the the half integer.
• Tracker.find_closed_orbit ignores Tracker.particle_ref when closed-orbit guess is provided.

Xtrack version 0.7.1

New features

• Qs added to results of Tracker.twiss.
• particle_ref can be optionally attached to the line. In that case it can be omitted when calling Tracker.twiss and Tracker.find_closed_orbit.