Add energy and particle specimen to hepmc3 run information attributes

[simonge]

Briefly, what does this PR introduce?

Additional parameters based on the selected afterburner settings are included in the output hepmc header, run info. This should allow them to be passed along the simulation chain.

What kind of change does this PR introduce?

• Bug fix (issue #__)
• New feature (issue #__)
• Documentation update
• Other: __

Please check if this PR fulfills the following:

• Tests for the changes have been added
• Documentation has been added / updated
• Changes have been communicated to collaborators

Does this PR introduce breaking changes? What changes might users need to make to their code?

no

Does this PR change default behavior?

no

[DraTeots]

I don't have a strong opinion on the above. But it would be good to choose vocabulary and be consistent across the code

[DraTeots]

Hello! Any updates on this?

[simonge]

Couple of notes before I try and remind myself where this got to.
AIDASoft/DD4hep#1147 - Should allow this information to be persisted through the simulation (and possibly used in the geometry construction)

The HEPMC_Merger will also need to copy across this information.

[simonge]

I believe for automatically determined files it works fine, I have only tested e-p of various energies. There may be some issues if the config clashes with the automatic values.

[DraTeots]

1. Are there any updates on this? Does this need a review or some work to be finished?

Thanks!

[simonge]

It works correctly for the files I've tested it on so could be reviewed, tested by someone else, and merged.

I think I need some information on how the afterburner is actually being used by everyone else to check it doesn't break their workflow or at least adds the correct functionality. How much effort would it be to set up some CI tests? This is something I've no experience with.

[veprbl]

@simonge Could you, please, rebase so that the diff is easier to review?

[simonge]

Has it not already been rebased? Looks like I might have messed up the order somehow.

[veprbl]

We also need an implementation in https://github.com/eic/eicSimuBeamEffects

[simonge]

We also need an implementation in https://github.com/eic/eicSimuBeamEffects

Are events generated using eicSimuBeamEffects used beyond comparing the position and beam momentum distributions at the IP?

I would propose all production events get passed through the afterburner independent of whether they already have beam effects added so that the run attributes can be added if they weren't already by the generator.

[simonge]

More importantly, perhaps, these attributes need to be compared between the input files and preserved in the merger eic/HEPMC_Merger#4

[veprbl]

We also need an implementation in https://github.com/eic/eicSimuBeamEffects

Are events generated using eicSimuBeamEffects used beyond comparing the position and beam momentum distributions at the IP?

This serves as the entry point for all pythia8 simulations for ePIC. It doesn't go through AB.
cc @bspage912

I would propose all production events get passed through the afterburner independent of whether they already have beam effects added so that the run attributes can be added if they weren't already by the generator.

On a similar topic, I'm not sure how we'd even roll out this soon for existing datasets. First step is to validate that this does not break anything, so we can ship a version of AB with this change.