Jpsi via the dimuon channel  in Run14 200 GeV (slides 33+) - Rongrong Ma
The TPC tracking efficiency on slide 42 for prod_high is lowest 30-40% centrality bin.
This has been  linked to non-monotonic behavior of #NGlobalTracks as a function on centrality (slide 43).
It is not clear why this happens. This issue will consulted with TPC experts.

Upsilon production in p+p 500 GeV - trigger efficiency studies - Leszek Kosarzewski
Small dependence of efficiencies on slide 7,8 on TOFmult and #Primaries was shown.
Asked to extract efficiencies as a function of pt (and ideally a mass). 
Use these to apply event-by-event weight of pairs when filling histograms from data.