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2) Random Track + Tower Matching - Look at the W signal region spectrum as a function of z-vertex (see if you get increased signal/background as a function of z. Should not have EEMC veto cut in this study because it already has a strong z dependence).
3) Ineffective Inefficient veto cuts from dead area of TPC/BEMC/EEMC
4) Possible beam backgrounds in BTOW/TPC caused inefficient veto cuts
5) No CMB crossing tracks leads to increased background because of inefficiency of veto cuts - Can study this in simulation by dropping any track that crossing the CMB
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8) If BTOW DB gains are very far from the truth this will cause an increased/decreased background in the signal region (stuff gets pushed up into or pushed out of the signal region)
9) L2W/BTH3 trigger background