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z4c

This page contains a full reference of all parameters available for the z4c module. At the bottom of the page you can find an example parameter block that can be used in your parameter file.

z4c

Z4c

Name:	bc_kind
Type:	keyword
Default:	sommerfeld
Range:	none, outgoing, sommerfeld
Description:	Outer boundary conditions for z4c, should really be Sommerfeld

Name:	kappa_1
Type:	double
Default:	0.02
Range:	[0,*)
Description:	Z4c damping parameter, should not really change unless you know what you’re doing

Name:	kappa_2
Type:	double
Default:	0.0
Range:	[0,*)
Description:	Z4c damping parameter, should not really change unless you know what you’re doing

Name:	eta
Type:	double
Default:	1.0
Range:	[0,*)
Description:	Shift damping parameter, should be 2/M or 2-2/M

Name:	eps_diss
Type:	double
Default:	0.0
Range:	[0,*)
Description:	KO dissipation strength, typically ~0.1

Name:	chi_floor
Type:	double
Default:	1e-11
Range:	[0,*)
Description:	Floor of conformal factor

Name:	alp_min
Type:	double
Default:	1e-11
Range:	[0,*)
Description:	Floor of lapse

Name:	eta_damp_radius
Type:	double
Default:	1e99
Range:	(0,*)
Description:	Eta decays as 1/r for r>this parameter

Name:	kappa_damp_radius
Type:	double
Default:	1e99
Range:	(0,*)
Description:	kappa_1 decays as 1/r for r>this parameter

Name:	theta_damp_radius
Type:	double
Default:	-1
Range:	[-1,*)
Description:	theta evolution damped as exp(-r/this parameter) -1 deactivates this

Name:	is_vacuum
Type:	bool
Default:	False
Description:	Is there matter?

Name:	adaptive_eta
Type:	bool
Default:	False
Description:	A la Lousto

Name:	adaptive_eta_a
Type:	int
Default:	1
Range:	[0,*)
Description:	A la Lousto

Name:	adaptive_eta_b
Type:	int
Default:	2
Range:	[0,*)
Description:	A la Lousto