Incorrect input parameters for NEST

[PavelKavrigin]

In 'clustering.py' some incorrect parameters for quanta generation with NEST are set, namely:

https://github.com/XENONnT/epix/blob/master/epix/clustering.py#L254-L255

A and Z should be the atomic mass and the atomic number of Xenon:

https://github.com/NESTCollaboration/nest/blob/cfecfdb8dc474eeff08163a361cfad58173ba93e/src/NEST.cpp#L746-L747

So the lines with these parameters should be changed to:

Xe_A = 131.293 Xe_Z = 54.0 classifier['A'] = [Xe_A]*7 classifier['Z'] = [Xe_Z]*7

As an illustration, we can use NEST to produce quanta using the NR spectrum which was generated from one of the AmBe calibration simulations (only elastic NRs were selected using a lineage clustering). Let's run it with A=infinity, Z=0, and then with A=131.3, Z=54.0, using the NR spectrum as an input, and apply g1=0.17, g2=14.1 (estimations from one of Henning's notes from June). Then we can compare it to the actual calibration measurement with base cuts applied to the data. This is the result:

[terliuk]

Great thanks, we should definitely fix it! But just a small clarification, for alphas it still has to be A=4 and Z=2 with type ion, right? It is only for WIMPs/NR that it should have correct number for A and Z, right?

[PavelKavrigin]

Yes, I think you are right, we've got this function for ions:

https://github.com/NESTCollaboration/nest/blob/cfecfdb8dc474eeff08163a361cfad58173ba93e/src/NEST.cpp#L487

Then the fix would be something like:

Xe_A = 131.293 Xe_Z = 54.0 classifier['A'] = [Xe_A, Xe_A, 4, Xe_A, Xe_A, Xe_A, Xe_A] classifier['Z'] = [Xe_Z, Xe_Z, 2, Xe_Z, Xe_Z, Xe_Z, Xe_Z]

[ramirezdiego]

Resolved in #44.