Generator for HF enhanced PbPb MC for dielectron analysis

[rbailhac]

pp HF events (charm or beauty with triggered on electrons...) are injected in Pb--Pb events. The number of injected events depends on the impact parameter of the Pb--Pb background collisions. Only particles coming from HF are injected (no underlying events). In the run script providing, no signal filtering is used (the full Pb--Pb background event is still kept). It may be changed for the final production.

[github-actions]

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