Units

There are three output files containing units parameters: xgc.units.bp in ADIOS2 format, units.m in MATLAB format and units.txt in plain text format.

For the name of the output variable, replace [species] with one of the following: e_, i_, i2, i3, i4, i5, i6.

xgc.units.bp
Printed when: always.   Output frequency: once at start/restart.

Output	Dimension	Units	Description
diag_1d_period	Scalar		Input parameter diag_1d_period, i.e. output frequency of 1D diagnostics.
eq_axis_b	Scalar	T	Magnetic field at the magnetic axis
eq_axis_r	Scalar	m	Major radius at the magnetic axis
eq_axis_z	Scalar	m	Height at the magnetic axis
eq_den_v1	Scalar	\(\mathrm{m^{-3}}\)	Plasma density of eq_den_v1. This value gives a characteristic density value ONLY when an analytic profile is used.
eq_tempi_v1	Scalar	eV	Ion temperature of eq_tempi_v1. This value gives a characteristic temperature value ONLY when an analytic profile is used.
eq_x_psi	Scalar	\(\mathrm{ T m^2 }\)	Poloidal flux (over \(2\pi\)) at the (first) X-point
eq_x_r	Scalar	m	Major radius at the (first) X-point
eq_x_z	Scalar	m	Height at the (first) X-point
[species]ptl_charge_eu	Scalar	\(e\)	Input parameter ptl_charge_eu, i.e., the species charge number (charge in units of elementary charge \(e\)).
[species]ptl_mass_au	Scalar	\(u\)	Input parameter ptl_mass_au, i.e., the species mass in atomic mass units (hydrogen mass \(m_{\mathrm{H}}~\approx~1u\)).
ptl_num	Positive integer		# of particle per MPI processor. This is not the same as the input parameter
sml_dt	Scalar	\(\mathrm{s}\)	Time step \(\Delta t\) in seconds. Note that the unit is different from the input parameter sml_dt which is given in units of toroidal transit time. Moreover, if a simulation is restarted with a different time step this output parameter will be updated to the last used step.
sml_totalpe	Scalar		# of MPI processors
sml_tran	Scalar	s	Ion transit time of [sml_en_order_kev] main ion. The default value of [sml_en_order_kev] is 0.2keV. \(\frac{2 \pi R} { \sqrt{2 E/m} }\)
sml_wedge_n	Scalar		# of wedges of simulation domain to cover \(2\pi\). For example, sml_wedge_n=2, the toroidal angle covers only between \(\varphi=0\) to \(\pi\) and the boundary is periodic.

units.m
Printed when: always.   Output frequency: once at start/restart.

Output	Dimension	Units	Description
diag_1d_period	Scalar	Positive integer	Same as in xgc.units.bp.
eq_axis_b	Scalar	T	Same as in xgc.units.bp.
eq_axis_r	Scalar	m	Same as in xgc.units.bp.
eq_axis_z	Scalar	m	Same as in xgc.units.bp.
eq_tempi_v1	Scalar	eV	Same as in xgc.units.bp.
eq_x_r	Scalar	m	Same as in xgc.units.bp.
eq_x_z	Scalar	m	Same as in xgc.units.bp.
psi_x	Scalar	\(\mathrm{ T m^2 }\)	Same as in xgc.units.bp.
ptl_ion_charge_eu	Scalar	\(e\)	Same as ptl_charge_eu in xgc.units.bp.
ptl_ion_mass_au	Scalar	\(u\)	Same as ptl_mass_au in xgc.units.bp.
ptl_num	Scalar		Same as in xgc.units.bp.
sml_dt	Scalar	\(\mathrm{s}\)	Same as in xgc.units.bp.
sml_totalpe	Scalar		Same as in xgc.units.bp.
sml_tran	Scalar	s	Same as in xgc.units.bp.
vth	Scalar	\(\mathrm{m/s}\)	Thermal velocity of the main ion with eq_temp_v1 energy. \(\sqrt{ e E_{eV}/m)\) This gives characteristic thermal velocity ONLY when an analytic profile is used.

units.txt
Printed when: always.   Output frequency: once at start/restart.

Output	Dimension	Units	Same as in xgc.units.bp.
eq_axis_B(T)	Scalar	T	Same as in xgc.units.bp.
eq_axis_r(m)	Scalar	m	Same as in xgc.units.bp.
eq_axis_z(m)	Scalar	m	Same as in xgc.units.bp.
psi_x(code unit)	Scalar	\(Tm^2\)	Same as in xgc.units.bp.
psi_x(MKS)	Scalar	Units	Same as in xgc.units.bp.
ptl_num(total)	Scalar	Positive integer	Total number of markers at the start of the simulation.
sml_dt(s)	Scalar	\(\mathrm{s}\)	Same as in xgc.units.bp.
sml_dt(tau)	Scalar	\(\tau\)	Same as the input parameter sml_dt given in units of toroidal transit time \(\tau\).
sml_dt(s)	Scalar	s	Ion time step size in seconds.
sml_totalpe	Scalar		Same as in xgc.units.bp.
sml_tran(s)	Scalar	s	Same as in xgc.units.bp.