Hello top snowmass group,
Is anyone else seeing something weird with lepton charge in the TTBAR_13TEV samples? I'm getting lots of same sign events and it doesn't seem to be due to charge mis-id since I'm also finding them in the truth record.  Here is an example:
                         (pt, phi, eta ) : charge
True Muon ( 42.1623 , 0.411772 , -2.77126 )  : -1 :
True Muon ( 26.747 , -0.218218 , 2.59109 )  : -1 :
Reco Muon 41.3628 Charge=-1 -2.77126
Reco Muon 27.3483 Charge=-1 2.59109
Jet #0 (55.3075 , 0.825672 , 0.810374 )
Jet #1 (49.6473 , 0.978317 , 0.334852 )
Jet #2 (28.1821 , -1.40152 , -2.2976 )

Here we have two muons, same sign and neither one seems to overlap with reconstructed jet.  I'm finding a substantial number of events like this.  I thought about heavy flavor decays but I would imagine that I would find the b-jet. This problem seems to be worse in the m=140 case than the mu=0 and mu=50.  Anyone have any ideas about what could be going on?

Thanks,
Rob Calkins