Imaginary part of frequency for SBPs

[benfernando]

Hi,

I'm new to GYRE and am running through the relevant MESA summer school modules (here, Gautschy 2016, labelled "PLS1" in http://cococubed.asu.edu/mesa_market/ew ... utschy.zip).

I've updated the inlists as needed and am getting things to run properly, but I notice that all the imaginary parts of the frequency (omega) appear to be zero in my runs, whilst in the original they are non-zero, indicated growing or decaying modes. The real parts are reasonably well matched (small differences I suspect are due to using slightly different points in the evolutionary model).

Is there a parameter somewhere that's different between the two versions of GYRE that's causing this to be the case, or am I just doing something wrong? My Gyre_nad.in is attached.

Thanks
Ben

[rhtownsend]

Hi,

I'm new to GYRE and am running through the relevant MESA summer school modules (here, Gautschy 2016, labelled "PLS1" in http://cococubed.asu.edu/mesa_market/ew ... utschy.zip).

I've updated the inlists as needed and am getting things to run properly, but I notice that all the imaginary parts of the frequency (omega) appear to be zero in my runs, whilst in the original they are non-zero, indicated growing or decaying modes. The real parts are reasonably well matched (small differences I suspect are due to using slightly different points in the evolutionary model).

Is there a parameter somewhere that's different between the two versions of GYRE that's causing this to be the case, or am I just doing something wrong? My Gyre_nad.in is attached.

Thanks
Ben

Hi Ben --

Welcome to the board! Your problem has a simple fix: you need to tell GYRE to include non-adiabatic effects. To do this, add the parameter

Code: Select all

nonadiabatic = .TRUE.

to the &osc namelist.

This parameter didn't exist in older versions of GYRE, as there were separate executables for adiabatic ('gyre_ad') and non-adiabatic ('gyre_nad') calculations. But now, there's just a single executable ('gyre'), and you need to tell it whether to run in adiabatic or non-adiabatic mode.

cheers,

Rich

[benfernando]

Hi Rich,

Great, that has indeed fixed it!

Much appreciated.

Ben