[Mesa-users] Noisy Brunt–Väisälä frequency

[Pedro Nuno David Gomes]

Dear MESA users,

I'm trying to calculate the square of Brunt–Väisälä frequency, N^2, for 
different life stages of a star with 1.5M_sun. However, the result is 
very noisy, and spiky. Besides this, I noticed that near the center N^2 
assumes negative (although very small) values.

How can I solve this?

I attach two figures that show the behavior I mentioned, and below I 
send my inlist.

Thank you for your help,

Pedro

------------------------------------------------------------

&star_job

	change_lnPgas_flag = .true.
         new_lnPgas_flag = .true.
         pgstar_flag = .true.

	save_model_when_terminate = .true.
	save_model_filename = 'final.mod'

	set_initial_age = .true.
	initial_age = 0

/ !end of star_job namelist

&controls

	initial_mass = 1.5
	initial_z = 0.02
	use_Type2_opacities = .true.
	Zbase = 0.02

         calculate_Brunt_N2 = .true.

	overshoot_f_below_nonburn_shell = 0.023
	overshoot_f_above_burn_h_shell = 0.023
	overshoot_f_above_burn_he_core = 0.023

	overshoot_f0_below_nonburn_shell = 0.005
	overshoot_f0_above_burn_h_shell = 0.005
	overshoot_f0_above_burn_he_core = 0.005

	photo_interval = 50
	profile_interval = 50
	history_interval = 1
	terminal_interval = 10
	write_header_frequency = 10

	mesh_delta_coeff = 0.8

         log_Teff_lower_limit = 3.71 ! (stop here)


/ ! end of controls namelist

&pgstar

/ ! end of pgstar namelist
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