FROM TH2F
constant
31.683313691442176+-0.6456668690486728
chi2/ndof = 20.393441836574038
plane
50.57862569695661+-4.051024996535622
invpt slope = -5.219031487607737+-0.5200044499703481
theta slope = -6.7496988730122+-3.3783447942081106
chi2/ndof = 19.515552722683168
from tgraph2D
constant
49.558780286862444+-2.63386009392093
chi2/ndof = 568.8519583495124
plane
83.06502976221446+-10.881083183580008
invpt slope = 9.02526301331915+-1.881970756053501
theta slope = -43.31396397214018+-9.32449332782698
chi2/ndof = 389.57919972036456