• GPU:

  • 1Dcartesian geometry now available.
  • Compilation simplified and better documented.
  • Improved performance of particle sorting.

• Features:

  • Relativistic field initialization now supports multiple species and both direction propagations.
  • Added the argument phase_offset in laser definitions such as LaserGaussian2D.
  • The LaserGaussianAM definition will only use one coordinate for its focus argument
    (the transverse coordinate of the focus in this geometry is zero).
  • Small improvements in PML for envelope model (AM and 2D).
  • Deprecated smilei_rand_max.
  • New namelist variables smilei_omp_threads and smilei_total_cores.

• Happi:

  • In Scalar, it is now possible to make an operation on scalars such as "Uelm+Ukin".
  • The list of available scalars can be obtained from getScalars().
  • New arguments xoffset and yoffset to shift plot coordinates.
  • New argument timestep_indices as an alternative to timesteps.
  • Changed coordinate reference for 2D probe in 3D or AM geometry
    (zero is the box origin projected orthogonally on the probe plane).

• Documentation:

  • Dark theme (click the switch on the bottom left, or set browser preferences).

• Bug fixes :

  • dump_minutes often failed to write some checkpoint files.
  • "auto" limits in ParticleBinning could fail with only one side on "auto".
  • CFL condition is more accurately determined in AMcylindrical and the feature timestep_over_CFL should be more reliable in that geometry.

• GPU support (not all features are supported at the moment)

  • Both AMD and Nvidia GPUs
  • Cartesian geometry in 2D and in 3D
  • Moving Window
  • Diagnostics: Field, Probes, Scalar, ParticleBinning, TrackParticles

• LaserEnvelope model:

  • Now compatible with PML boundaries
  • In AMcylindrical geometry, the number of modes can be greater than 1 (only affects electromagnetic
    fields and the densities, not envelope or susceptibility)
  • multi-level tunnel ionization creates multiple electrons, improving the sampling

• Diagnostics

  • Much faster DiagFields (speedup ~ x3)
  • DiagFields and DiagProbe: new parameter datatype
  • DiagPerformances: new parameter cumulative

• Collisions: new parameter time_frozen

• Species: in AMcylindrical geometry, the initial drift velocity profiles may be defined
  either in the x,r,θ directions with mean_velocity_AM or in the x,y,z directions with mean_velocity.

• Lasers: changed the delay and phase of gaussian lasers at high incidence to make them consistent between boundaries.

• Happi:

  • Operations in Fields, Probe, and ParticleBinning may now accept physical constants, units,
    or basic functions such as exp() or sin()
  • Probe has a new method changeField
  • Open has a new argument pint to disable the Pint package
  • multiPlot and multiSlide have a new argument legend_font
  • The title can be formatted with a placeholder for the current time in an animation
  • Various performance improvements

• Friedman filter: now available in geometries 1Dcartesian and AMcylindrical (previously available only in 2Dcartesian)

• Lehe solver for Maxwell equations now available in AMcylindrical geometry

• Bugfixes:

  • Compilation fixed for the newest version of GNU make
  • Poisson Solver correction was not properly accounted for with SDMD
  • Bug correction using Monte-Carlo radiation and multiphoton Breit-Wheeler processes with checkpoints
  • C++11 compilation issue
  • Reading particle weights and momenta from hdf5 file
  • PML are now compatible with dynamic load balancing.
  • solved segfault with Multiphoton Breit-Wheeler process in AMcylindrical geometry
  • Collisional ionization incorrect for :math:Z^\star = Z-1
  • Field.getAxis was not accounting for the timestep
  • Bug correction in 1D relativistic Poisson solver

• Experimental

  • B-TIS3 interpolation scheme to reduce the effects of numerical Cherenkov radiation is implemented up to interpolation order 2
  • New diagnostic: DiagNewParticles records particle information when they are created by ionization or other mechanisms

• For developers: new table management for Monte-Carlo physical processes (transparent to users)

• Perfectly Matched Layers boundary conditions for EM fields (+2D Cartesian benchmark).
• Improved performance for ARM-based processors including the Fujitsu A64FX
• Improved performance for GNU, LLVM, arm-clang and Fujitsu compilers on all types of architectures
• Lasers can be injected from all boundaries
• Flag ponderomotive_dynamics removed from Species block. All Species interact with LaserEnvelope if present
• Option to create neutrons for D-D fusion
• Collisions can be done less often
• Lasers can be injected from all boundaries
• New 4th-order non-standard FDTD solver M4
• Timestep dependent field interpolation scheme
• LaserOffset:
  • may be re-used from a previous simulation
  • available from ymin, ymax, zmin and zmax
  • has new arguments fft_time_window and fft_time_step
• Diagnostics:
  • Probes can include components of the Poynting vector PoyX, PoyY, PoyZ
  • Probes can be time-integrated
  • ParticleBinning diagnostics may accept "auto" as axis limits
  • Particle IDs may be modified in the DiagTrackParticles.filter (8 available bits)
  • Screens may have a cylinder shape
  • Scalar diagnostics for AM geometry now available
  • happi ParticleBinning now uses the keyword average instead of sum
• Bugfixes:
  • Poynting scalars behaviour with several patches, or with checkpoints
  • Densities too low are put to 0 to avoid underflow
  • Prescribed fields in 2D
  • ellipticity = -1. was doing +1.
  • Setting units in happi's TrackParticles was wrong (for plotting only)
  • Current communication correction for FIR filters
  • Fix for particle merging segmentation fault in spherical and Cartesian modes
  • Tracked particles with the vectorized mode
  • momentum_initialization from a file did not take the proper file

• Single-domain multiple decompositions
• New 4th-order non-standard FDTD solver Bouchard for 2D and 3D geometries
• New method for current filtering with a user-provided FIR kernel for 1D, 2D and 3D geometries
• Diagnostics may now have a name (useful during post-processing)
• Laser Envelope:
  • linear and circular polarization
  • ionization model
  • normalized laser frequency can be different from 1
• Particles can be imported from a file
• Some profiles can be imported from a file
• Coulomb logarithm may be multiplied by a constant factor
• Happi:
  • handles fonts
  • time slider available with multiple plotting
  • vsym option for symmetric graph
  • getXmoved now accounts for requested units
  • Tracked particles can be selected before sorting
• Bugfixes:
  • Fix in the vectorized projection at order 4
  • Photons could not be read from numpy array
  • DiagFields with time_average did not work for densities
  • Prescribed fields caused unstable real fields
  • Initialisation from numpy or hdf5 caused wrong weights in AM geometry
  • Better positionning of collisionally-ionised electrons
  • Fix segfault from thermalizing boundary
  • Running a simulation displayed the wrong version v4.4

• Changes:

  • Current filtering with adjustable number of passes per dimension
  • Improved axial boundary conditions for AMcylindrical geometry
  • Units in RadiationSpectrum diagnostic are more consistent with that
    of ParticleBinning
  • Ionisation current at fourth order of interpolation
  • Correction for :doc:collisions as suggested in [Higginson2020]_

• Bugfixes:

  • PrescribedField was sometimes not applied by some OpenMP threads
  • Scalar Ukin_bnd was sometimes wrong with load balancing
  • Scalar Urad was sometimes wrong with moving window
  • On some systems, particles IDs were incorrect with ionization

• New radiation tables : old tables not valid anymore, and input files using QED processes need to be updated
• Radiation spectrum diagnostic
• Prescribed fields
• Laser Envelope: equation solver with reduced numerical dispersion
• AM geometry : subgrid in DiagFields, species-related currents and density in probes
• LaserOffset not recomputed after restart
• Bugfixes

More details in the doc.

Additional features :

• AMcylindrical : envelope, ionization, additional diagnotics, number of ppc per direction, binomial current filter, poisson solver, non-separable laser initialization per mode, improved diag field nomenclature
• Particle injector
• More control over the moving window movement
• More control over the regular position initialization in Cartesian geometries
• Bugfixes

Experimental features:

• Particle merging
• Nuclear reactions
• Interface with the PICSAR library for AM spectral solver

• Different convention for circular polarization amplitude
• Binomial filter in Cartesian 3D bug fix in parallel implementation
• 1D and 2D laser envelope model
• Cylindrical geometry with azimuthal Fourier decomposition (beta version)
• Compatibility between various ionization and QED models
• Bugfixes

• Probe diagnostics of currents and density per species
• Field diagnostics with more than 2^32 points
• Bugfixes
• Disable usage of -ipo to compile

Some details in the doc.