Repeat calculation of globule flow, shock, and shell, but for the adiabatic case

[will-henney]

This is probably not realistic for most globules, but there may be an adiabatic part of the outer flow before the shock. So this will be a first step towards calculating the effects of that.

• [x] Find the adiabatic version of the Bernoulli equation
• [x] Use it to find velocity and Mach number as a function of radius for an adiabatic flow

[will-henney]

Adiabatic case will take over when density is low enough that heating timescale exceeds dynamic timescale

[will-henney]

At the ionization front, the heating time will generally be short. For instance, in the case of the LDN 1616 globule it works out to be about 10% of the dynamic time:

[will-henney]

We need to work out the enthalpy for the adiabatic case. I think that that Shu Volume 2 has something on this

[will-henney]

It seems likely that we are comfortably within the isothermal regime for the globules in M1-67.

The above calculation suggests that $r_0 n_0$ is significantly larger in the WR globules, compared with in LDN1616, which means we should be firmly in the recombination-dominated regime

[will-henney]

For completeness, here is my solution for the adiabatic globule flow

More details are in a PDF in the will-documents/ folder of the repo