WIP: Srh/therm src calc

[shaunhaskey]

No description provided.

[lstagner]

Looking at this more carefully today. Is there any reason why you cant store the thermal ion birth profile like we do with the fast-ion birth profile?

[shaunhaskey]

@lstagner Not sure if this is what you meant, but I'll document some of what I was thinking. The reason things were done differently is to avoid double counting because of the different generations of neutrals (particularly for the halo where they get squashed). There is also the question of whether you are talking about the source for electrons, or the source for D+.

For 'fast' neutral beam injectors and fast D+, it is fairly straightforward because all ionization and charge exchange processes are a source of fast D+. Charge exchange in this case: D0_fast + D+_thermal -> D+_fast + D0_thermal, is a sink for thermal D+ and fast D0, and a source for fast D+ and thermal D0.

If we start worrying about thermal D+ (or e-), then things are more complicated mainly because charge exchange with D+ is not a source of D+. All of the neutrals in any generation are either lost to charge exchange, impact ionization, or they left the grid:

Charge exchange
(1) D0 + D+ -> D+ + D0
(2) D0 + C6+ -> D+ + C5+
Impact ionization
(3) D0 + e -> D+ + e + e
(4) D0 + C6+ -> D+ + e + C6+
(5) D0 + D+ -> D+ + D+ + e-

If we want to calculate the source rates for D+ we want to include everything except (1) which is not a source because there is no increase in the # of D+ on RHS. That neutral ends up being reborn in the next generation. Fortunately it is easy to remove this contribution because you just subtract the number of neutrals from the subsequent generation. Eventually they will all get counted at some generation.

If we want to calculate the source rates for e: (1) and (2) are not sources, this is harder to separate out in FIDASIM at the moment. because we don't follow what happens to the C5+ that got a hold of the electron.

[shaunhaskey]

@lstagner Let me know if you can see a better way to implement this

[heidbrin]

Luke, None that I can think of. William (Bill) Heidbrink Department of Physics and Astronomy University of California Irvine, CA 92697 949-824-5398 (office) 949-824-2174 (fax)

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[shaunhaskey]

@prechelg I resolved the conflicts so it is in a state closer to merge ready. I will test a few things (I need to bring all of my associated scripts up to date with master), then we can discuss the details of the implementation and any improvements that might (will) be needed before possibly merging