DD and DT Fusion Possible?

Can Geant4 today simulate fusion reactions?

I’ve seen some indications that it can and can’t simulation fusion.

Thank you.

in examples/extended/hadronic/hadr03 there is a macro fusion.mac

Update: I wrote my own code and also experimented with had03.
I found I couldn’t get DD fusion to happen with either code between 10-50keV. This is around the full electric potential of a desktop IEC plasma fusion device. At MeV energies I observed both DD fusion pathways.

Hello,

what version of Geant4 do you use? Cross sections DD and DT were updated in 10.7.

VI

Geant4 10.07.02.
I downloaded and installed the newest version about a week ago.

Hello,

you need G4ParticleInelasticXS cross section for deuterons. This cross section is used only in QBBC PhysicsList.

VI

I wasn’t using that physics list. I will test and respond.
Where do you find out what cross sections exist in a particular physics list?

Thank you for your responses.

Using QBBC didn’t make a noticeable difference when using Had03. Still no fusion products produced. I’d like to know if anyone else could achieve DD fusion with < 100 keV energies, again, as exists in IEC DD fusion devices.

It would be much appreciated to know if it’s an issue with my code (or understanding) or if G4 just isn’t ready for it. Thank you.

fusion.mac.txt (267 Bytes)
fusion.out.txt (2.1 KB)
PhysicsList.cc.txt (5.2 KB)

Thank you for your response.
Your output is the same as what I get at around 10 keV; no He3 or Tritium generated from either of the 2 fusion pathways. I did run the simulation in Had03.

I did a back-of-the-envelope calculation, and I think i need ~3e10 deuterons before seeing an event. The estimate is based on the electric potential and current of the IEC device.

I hit a limit about 2^31 particles; ~2.147 billion.
Is there a way to increase the number of particles for beamOn?

Again thank you.

Yup. Geant4 uses a G4int (signed int) for the event ID, so that’s the limit of beamOn.

If you set up your own seeding of the random engine (for instance, my experiment uses libuuid), then you can run multiple jobs which will be independent of one another.

you could also create multiple particles per event, like /gun/number 10000. Don’t know if the rest of your code is compatible — but if so, this would be a really quick test :slight_smile:

Hello,

it is not the only place where cross section is small. In all such cases biasing methods should be applied. The most simple - multiply cross section by a factor and take this into account in further analysis of results.

VI

Thank you very much!
This everyone here in this thread alone has taught me a lot and given me direction.

Hello.
I had modeled DT fussion experiment in 10.06.p2 and 10.07, and find that it work pretty good when using physics list QGSP_BIC_AllHP. Also, i find that tritium in the target should be declared by setting tritium isotope, then tritium as element, and only after that tritium as material component in the target. In my simulation it’s look like this:

G4Isotope*H3 = new G4Isotope("H3", 1, 3, 3.016*g/mole);

G4Element* elT = new G4Element("Trirtium", "T", 1);
elT->AddIsotope(H3, 100*perCent);

G4Element*elTi = new G4Element("Titan", "Ti", 22, 47.87*g/mole);
G4Material*target_mat = new G4Material("Titanium Gidrid", 3.76*g/cm3, 2);
target_mat->AddElement(elT, 2);
target_mat->AddElement(elTi, 1);

It works pretty well with deuteron energies around 20-150 keV, but i didn’t check DD fusion in this model.

1 Like

Hello,
Thank you to all the contributors to this thread. I was wondering if the proton tritium reaction is included and if geant4v11 handles inverse kinematics.
Many thanks!

So far as I know, G4 (including v11, only handled inverse kinematics (what they call the adjoint Monte Carlo) for electromagnetic interactions. I think the problem with doing it for hadronic interactions is that essentially “every” interaction involves killing the projectile and producing all new secondaries.

Hmmm, please forgive me if I am confusing this, though I was rather enquiring on the two body modelling of reactions amongst a heavy and light nuclei and the resultant angular yields.

Sorry! I misunderstood.

No problem at all. I am just trying to understand the extent of the hadron inelastic capability under QBBC as Vladimir discusses above as I am not obtaining neutrons from triton H2 reactions. DD and DT work fine.
This cross section data seems to be available under G4ParticleXS4.0 but when i dont see the neutrons being produced for the H(t,n)He reaction. Which Physics list do I need to call? @civanch Ps sorry for the ping and thanks for your help.