[Mesa-users] Question

[Warrick Ball]

Hi Ann,

If you want to know more about a particular item in the history output, 
the first place to look is the defaults file (if you haven't already) at 
$MESA_DIR/star/defaults/history_columns.list.  I presume from there you 
can see that `log_Lnuc` is the sum of the energy produced by nuclear 
reactions (excluding neutrino losses and photodisintegrations). 
Presumably `log_Lnuc_erg_s` is the same thing in units of erg/s rather 
than Lsun (solar luminosities).

`total_energy` is quite different.  This is an integral of all the 
energies in the star, not energy *rates* like the nuclear reactions.  I 
encourage you to search for the `total_energy` in the source code with 
e.g.

     grep total_energy $MESA_DIR/star/p*/*.f*

and sift through the output.  I've just done so myself and it looks like 
the total energy is computed by the subroutine 
`eval_total_energy_integrals` in `star/private/star_utils.f90`, which 
itself calls `eval_section_total_energy_integrals` over the whole star. 
>From the function call alone, it looks like `total_energy` is the sum of 
the internal, gravitational potential, linear kinetic and rotational 
kinetic energies.  I would presume this is in ergs.

Cheers,
Warrick






------------
Warrick Ball
Postdoc, School of Physics and Astronomy
University of Birmingham, Edgbaston, Birmingham B15 2TT
W.H.Ball at bham.ac.uk
+44 (0)121 414 4552


On Sat, 19 Jan 2019, d10631026 at gapps.fg.tp.edu.tw wrote:

> 
> Dear mesa users:
> 
> 
> Could I ask what is the difference between log_Lnuc_ergs_s and total_energy in the history.data of example_ccsn_IIp?
> 
> Thanks a lot!
> 
> 
> Ann  
> 
> 
>