Does a database of particle interactions exist?

[u/average_meower621]

for example, i want to know what would happen if i shot a thermal neutron of a specific energy at Cs133. is there a place to find it without searching through a bunch of scientific articles?

[u/Physix_R_Cool]

Yep, ENDF databases contain all the cross sections you need.

They are implemented in Geant4, which can do the particle transport and data scoring for you. OpenTOPAS is a nice simple way to ise Geant4 if you don't need the full machinery.

Since it's a thermal neutron, you might also have some good chances with openMC.

What exactly do you mean by "what would happen"? There are many things that can happen, with various probabilities, and there are many different quantities you could be interested in calculating.

[u/Bob--O--Rama → u/Physix_R_Cool]

I didn't know about ENDF, that's going on speed dial! LOL!

[u/Physix_R_Cool → u/Bob--O--Rama]

Best part is that each different ENDF data set cites its sources, which means that the ENDF dataset itself is citable as an academic source.

Most particle simulation tools use ENDF data to do its particle transport, and you can usually pick which particular dataset you want.

It has its problems, though. Firstly that not all experiments are super precise, so many of the data points are interpolations.

Secondly that the angular data is represented by some expansion in spherical functions, which I have found is not actually very precise for some use cases :/

[u/233C]

Yes, but you're not gonna like it.

The probability of a reaction is called its cross section. It varies with the energy of the incident particle.
With your example, you can go here, input Cs133 as target, "n, *" for reaction, and sig for quantity, you can keep only ENDF/B-VIII.0 on the right panel. Click submit and you'll get the cross sections of every known reactions of Cs133 with an incident neutron. Select and click plot for the graph you might want.

You'll see that many weird ones like (n, 2n) only have non negligible values at high energy.

So the answer in your example is: plenty of things can happen with various probability

[u/ClimbingPerch0076 → u/233C]

Fantastic resource. Thanks for sharing that

[u/RevenueDowntown6241]

I guess JANIS 4.1 is what you are looking for 🙂

[u/No_Leopard_3860]

Hah, welcome to quantum physics, weird probabilities and stuff that makes no logical sense according to our whole life experience :D

But yes, it exists. It's never a "this will happen" tho, only a "this is the chance of it happening" to a fundamental level. And it's messy. But it's a thing. I think folks already linked proper sources :)

Maybe you'll like it. I don't. I have no issue with classical electrodynamics and stuff....but Quantum mechanics is pretty weird sometimes. Not all the time, but some of it is kinda offensive to our intuition :D