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Inconsistencies in handling of Bs lifetimes in time-dependent CPV models and EvtCPUtil
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In evt.pdl (and also in the LHCb particle property table) there are inconsistencies between the lifetime values given for B_s0, and the two eigenstates B_s0H and B_s0L. In particular, the B_s0 value is not the proper average of the two eigenstates, which may or may not be intentional.

However, this does cause problems because the way that EvtCPUtil and the different decay models that account for TDCPV, e.g. EvtPVVCPLH and EvtSSDCP, use the various lifetimes is different and inconsistent. For example, EvtCPUtil::incoherentMix uses only the lifetimes of the B_s0H and B_s0L eigenstates as input and calculates both Gamma and Delta Gamma from them, while EvtPVVCPLH uses the B_s0 lifetime to calculate Gamma and the B_s0H and B_s0L lifetimes to calculate Delta Gamma, and EvtSSDCP uses the B_s0 lifetime to calculate Gamma and then takes Delta Gamma as an input parameter to the model.

We should make a thorough review of the various time-dependent CPV models and utility classes, remove any that are no longer needed, and then make sure that the rest act in a consistent manner. As part of this we should decide how to set the various lifetime values in evt.pdl and similarly in the LHCb particle tables. Finally, this should also be documented.

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