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Allow helium3 candidates to be created

Hendrik Jage requested to merge hjage_add_ions into 2024-patches

This MR adds two changes that allow helium candidates to be created for the Run3 HLT2 trigger.

  1. Add helium3 (and helium4/alpha) to the list of known particles in the FunctionalParticleMaker
  2. Take into account that helium is double charged, when creating the LHCb::Particle

While the former change is straight forward, the latter requires:

  1. The possibility of q\neq 1 to be considered, when assigning a track to be a particle/antiparticle in the FunctionalParticleMaker
  2. To modify the state2Particle function, in order to scale the momentum and it's covariance matrix correctly when converting the track state (x,y,t_x,t_y,q/p) to a particle state. To scale the covariance matrix correctly, a modification to JacobdP4dMom in LHCb (LHCb!4512) is necessary, as well.

As these are modifications to an integral part of the LHCb software and the case of q\neq1 is quite rare, I didn't go for a general implementation, but made sure the new functions are only considered if q\neq1 is the case.

Deuterons along are significantly easier to add and therefore treated separately here: !3839 (merged)

Finally, the name for helium3 in the list of known particles (He3 instead of He3[0.0]), is related to these MRs: lhcb-conddb/DDDB!131 (merged) and LHCb!4579

Edited by Hendrik Jage

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