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The MCPL_input McStas Component

Source-like component that reads neutron state parameters from an mcpl-ﬁle.

Source-like component that reads neutron state parameters from a binary mcpl-ﬁle.

MCPL is short for Monte Carlo Particle List, and is a new format for sharing events between e.g. MCNP(X), Geant4 and McStas.

When used with MPI, the –ncount given on the commandline is overwritten by #MPI nodes x #events in the ﬁle.

Example: MCPL_input(ﬁlename=voutput,verbose=1,repeat_count=1,v_smear=0.1,pos_smear=0.001,dir_smear=0.01)

Parameters in boldface are required; the others are optional.


Name	Unit	Description	Default



ﬁlename	str	Name of neutron mcpl ﬁle to read	0
polarisationuse		If !=0 read polarisation vectors from ﬁle	1
verbose		Print debugging information for ﬁrst 10 particles read	1
Emin	meV	Lower energy bound. Particles found in the MCPL-ﬁle below the limit are skipped	0
Emax	meV	Upper energy bound. Particles found in the MCPL-ﬁle above the limit are skipped	FLT_MAX
repeat_count	1	Repeat contents of the MCPL ﬁle this number of times. NB: When running MPI, repeating is implicit and is taken into account by integer division. MUST be combined with _smear options!	1
v_smear	1	When repeating events, make a Gaussian MC choice within v_smear*V around particle velocity V	0
pos_smear	m	When repeating events, make a ﬂat MC choice of position within pos_smear around particle starting position	0
dir_smear	deg	When repeating events, make a Gaussian MC choice of direction within dir_smear around particle direction	0
preload		Load particles during INITIALIZE. On GPU preload is forced	0