FROM TH2F
constant
25.5475275260846+-0.4256620011218912
chi2/ndof = 22.806376205648693
plane
25.031308577362104+-1.1479358014679097
invpt slope = -4.475623349471814+-0.3587662340923483
theta slope = 15.966865535513113+-0.9449841920701388
chi2/ndof = 19.08852500314564
from tgraph2D
constant
45.44012630458664+-1.8675684998758204
chi2/ndof = 561.5377496768838
plane
18.117536014185575+-3.6043373593877805
invpt slope = 6.425543220218537+-1.342844100095787
theta slope = 22.722208112535146+-3.664558521618625
chi2/ndof = 392.5066594926959