[mesa-users] Kjeldsen correction in astero module

[Santiago Andres Triana]

Dear Dennis, Kuldeep & MESA users,

Thanks for the hints! I did look into the simplex_results.data and the
'a_div_r' column was all zeros. I think the reason is that I was
providing a 'delta_nu' in the inlist slightly above (about 10%) of the
observed delta_nu mean (I was thinking that it was better to use a
value as close as possible to the asymptotic delta_nu there). This
leads to a correction_b <1 and therefore no correction overall.

Additionally, I had not provided the orders in l0_n_obs(:). It was
bound to fail indeed.

Now I'm a bit further after providing the radial orders and providing
the correct delta_nu to match the observed mean (or letting the module
calculate it by setting delta_nu=-1). The only thing is that there is
a drop in delta_nu_model as soon as the module starts using the
l0_freqs (instead of using the Brunt-Vaisala frequency) to calculate
it (see the figure). In my earlier experiments this drop was
preventing me from finding good chi2_radial. Now I can tweak
delta_nu_sigma to make the module calculate delta_nu_model from
l0_freqs sooner.

Hope this make any sense, please let me know otherwise. Again, many
thanks for further ideas!

Cheers,

Santiago

On Mon, Feb 16, 2015 at 10:21 PM, Dennis Stello
<stello at physics.usyd.edu.au> wrote:
> Hi Santiago,
>
> It sounds to me that what you are looking for is in the simplex results
> file....did you you look there?
>
> Cheers
> Dennis/
>
> -------
> DENNIS STELLO | Senior Lecturer
> School of Physics A28 | Faculty of Science
>
> THE UNIVERSITY OF SYDNEY
> Rm225, K90 | The University of Sydney | NSW | 2006
> T +61 2 9036 5108  | F +61 2 9351 7726
> E stello at physics.usyd.edu.au  | W http://www.physics.usyd.edu.au/~stello/
>
>
>
> On Sat, 14 Feb 2015, Santiago Andres Triana wrote:
>
>> Hi MESA users,
>>
>> Playing around with the astero module and simplex, I noticed that the
>> frequencies, as reported in the sample_#.data files, are not
>> corrected. They seem to be the raw, uncorrected  frequencies from gyre
>> although I have specified the 'kjeldsen' method in
>> inlist_astero_search_controls.
>>
>> The inlist is attached. The relevant snippet is this:
>>
>>    ! surface corrections
>>      correction_scheme = 'kjeldsen' ! options are
>>         ! 'kjeldsen'   Correction of Kjeldsen et al. (2008)
>>         ! 'cubic'      Cubic correction of Ball & Gizon (2014, eqn 3)
>>         ! 'combined'   Combined correction of Ball & Gizon (2014, eq 4)
>>         ! ''           no corrections
>>      correction_factor = 1
>>         ! use this fraction of the correction; set to 0 to skip doing
>> corrections.
>>      l0_n_obs(:) = -1 ! the observed radial orders (ignored if < 0)
>>         ! the observed radial orders are used in calculating surface
>> corrections
>>         ! if <= 0, use default calculation for radial orders
>>      correction_b = 4.25d0
>>
>>      save_next_best_at_higher_frequency = .true.
>>      save_next_best_at_lower_frequency = .true.
>>
>>
>> I'm convinced that I'm doing something silly somewhere but cannot
>> figure out where... any hints or comments are very much appreciated.
>> Many thanks in advance!
>>
>> Cheers,
>>
>> Santiago
>>
>
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