Checkpoint Restart Outputs

This page is generated from in-code XGC I/O metadata by utils/python/document_outputs.py.

Checkpoint-restart variables. These files are written for restart fidelity and are not ordinary analysis diagnostics.

restart_dir/xgc.restart*.bp

Variable	Units	Description
3db_rampup_factor	dimensionless	Restart value of the 3D perturbed magnetic-field ramp-up factor.
apars	T m	Restart value of perturbed parallel vector potential \(A_{\parallel}\) on toroidal planes and mesh nodes.
cden0_rmp	m^-3	Restart value of axisymmetric charge-density state used for RMP/electromagnetic perturbations.
checkpoint_version	Positive integer	Version index indicating the format of this restart file.
dpotsave	V	Restart history of perturbed electrostatic potential on toroidal planes and mesh nodes.
inode1	Positive integer	Number of local mesh nodes assigned to each MPI rank in the checkpoint domain decomposition.
jpar0_rmp	A m^-2	Restart value of axisymmetric parallel current-density state used for RMP/electromagnetic perturbations.
jpara_diff_integral	A m^-2	Cumulative controller sum of the parallel current-density difference used by current drive.
jpara_diff_previous	A m^-2	Smoothed previous parallel current-density difference used by the current-drive derivative controller.
loop_voltage	V	Restart value of the loop-voltage profile on mesh nodes.
neu_node_dens	m^-3	Checkpointed neutral background density on mesh nodes.
neu_node_temp	eV	Checkpointed neutral background temperature on mesh nodes.
neu_weight_lost_ebin	simulation-particle weight	Checkpointed cumulative neutral marker weight lost in wall energy bins.
neu_weight_sum_lost	simulation-particle weight	Checkpointed cumulative sum of neutral marker weight lost to walls.
neu_weight_wall_lost	simulation-particle weight	Checkpointed cumulative neutral marker weight lost on each wall element.
nmup1	Positive integer	Number of perpendicular velocity grid points in f0 checkpoint arrays.
nnode	Positive integer	Number of 2D mesh nodes.
nphi	Positive integer	Number of toroidal mesh planes \(N_{\mathrm{planes}}\).
prefix + "max_used_gid"	Non-negative integer	Largest globally unique marker-particle ID already assigned for this species.
rhs_offset0	m^-3	Axisymmetric right-hand-side density offset used when restarting the Poisson/charge solve.
sheath_ilost	simulation-particle weight	Checkpointed cumulative lost ion marker weight \(w_0 w_1\) on toroidal planes and wall elements.
sheath_lost	simulation-particle weight	Checkpointed cumulative lost marker weight \(w_0 w_1\) on toroidal planes and wall elements.
sheath_nphi	Positive integer	Number of toroidal planes in sheath checkpoint arrays.
sheath_nwall	Positive integer	Number of wall elements in sheath checkpoint arrays.
sheath_pot	V	Checkpointed sheath potential on toroidal planes and wall elements.
sp_name + "_f0_delta_T"	eV	Restart value of species temperature perturbation added to the analytic f0 background on mesh nodes.
sp_name + "_f0_delta_n"	m^-3	Restart value of species density perturbation added to the analytic f0 background on mesh nodes.
sp_name + "_f0_delta_u"	m s^-1	Restart value of species flow perturbation added to the analytic f0 background on mesh nodes.
sp_name + "_f0g"	m^-3 eV^-1	Species residual/grid contribution to the f0 distribution function on [toroidal plane, perpendicular velocity, mesh node, parallel velocity].
sp_name + "flag"	integer flag	Escaped-particle status flags for this species.
sp_name + "gid"	index	Globally unique marker-particle IDs for this species.
sp_name + "nphase"	Positive integer	Number of columns in the species particle phase checkpoint array.
sp_name + "num_arr"	Non-negative integer	Number of checkpointed marker particles for this species written by each MPI rank.
sp_name + "num_total"	Non-negative integer	Total number of checkpointed marker particles for this species across all MPI ranks.
sp_name + "off_arr"	Non-negative integer	Global particle-array offset for this species for each MPI rank in the checkpoint.
sp_name + "phase"	[m, m, rad, m, dimensionless, dimensionless, J/T, dimensionless, m^-3]	Species particle phase checkpoint array with columns [R, Z, phi, rho, w1, w2, mu, w0, g], where \(R\), \(Z\), and \(\phi\) are the cylindrical coordinates of the particle, \(\rho\) is the parallel gyroradius (proxy for \(v_{\parallel}\)), \(w_1\) is the delta-f weight, \(w_2\) is a weight used in the weight evolution equation, \(\mu\) is the magnetic moment, \(w_0\) is the full-f weight (from importance sampling), and \(g\) is the marker density.
sp_names[species.idx] + "_f0_df0g_persistent"	m^-3 eV^-1	Persistent residual df0g distribution retained for later particle transfer on [toroidal plane, perpendicular velocity, mesh node, parallel velocity].
sp_names[species.idx] + "_f0_df0g_persistent_counter"	source-application count	Age counter for persistent residual df0g entries on [toroidal plane, perpendicular velocity, mesh node, parallel velocity].
time	s	Simulation time of step in seconds.
timestep	Non-negative integer	Simulation time step stored in the checkpoint.
totalpe	Positive integer	Number of MPI ranks used when the checkpoint was written.
vpdata	Positive integer	Number of parallel velocity grid points in f0 checkpoint arrays.