FROM TH2F
constant
40.07248578287475+-1.0406921529316584
chi2/ndof = 61.08610488413175
plane
-300.3511226362445+-10.410874286177274
invpt slope = 9.72082428688302+-1.147202032071958
theta slope = 298.65560502055894+-9.008696648183149
chi2/ndof = 32.279857448054784
from tgraph2D
constant
100.34941898411046+-7.703848012817059
chi2/ndof = 2373.9709681331724
plane
-180.8401852829618+-63.468355289962446
invpt slope = 8.432842496986849+-6.493900438187677
theta slope = 225.13895547142982+-50.25848652883792
chi2/ndof = 1621.2738993824976