[Mesa-users] Nuclear binding energy released

[Francis Timmes]

depends on how eps_nuc is defined, yes?

somewhat surprisingly eps_nuc wasn't precisely defined in previous 
mesa instrument papers, but this will change soon enough. 

fxt



> On Jan 25, 2019, at 11:52 AM, David Arnett via Mesa-users <mesa-users at lists.mesastar.org> wrote:
> 
> That misses the mass defect, which is tiny except for H burning, but should be detectable with helioseismology.
> 
> On Thu, Jan 24, 2019 at 9:26 PM Bill Paxton <paxton at kitp.ucsb.edu> wrote:
> for energy from burning with nuclear reaction neutrinos subtracted, you could use cumulative_nuclear_heating
> 
> where
>            s% total_nuclear_heating = dt*dot_product(s% dm(1:nz), s% eps_nuc(1:nz))
> and
>            s% cumulative_nuclear_heating = &
>                s% cumulative_nuclear_heating_old + s% total_nuclear_heating
> 
> you can add cumulative_nuclear_heating to your history columns list.
> 
>  -b
> 
> 
>> On Jan 24, 2019, at 3:44 PM, Josiah Schwab via Mesa-users <mesa-users at lists.mesastar.org> wrote:
>> 
>> Hi Shiv,
>> 
>> I want to compute the nuclear binding energy released by burning over the whole simulation.
>> 
>> In that case, you also might consider computing the binding energy at the first step, storing that value, calculating it at subsequent steps, and then taking the difference.
>> 
>> Note that the mass fractions are in s% xa(i,k) and there is also a binding energy value on chem_isos, i.e. chem_isos% binding_energy(ci).
>> 
>> The bookkeeping might be complicated if your models have mass loss though.
>> 
>> Hope that helps,
>> Josiah