FROM TH2F
constant
50.719796878901775+-1.0388188557109999
chi2/ndof = 38.32042626531046
plane
-57.10440215026064+-7.081207514693865
invpt slope = 2.7295909255390383+-1.0007521650142046
theta slope = 97.38278908683563+-6.280802190945154
chi2/ndof = 34.54551608837391
from tgraph2D
constant
91.7951937709574+-5.389274962209047
chi2/ndof = 1510.3027965227902
plane
-18.013557297712424+-41.470239400984624
invpt slope = -0.9904438721562818+-3.9524784257510546
theta slope = 99.81621938623714+-36.471837109783834
chi2/ndof = 1362.1976002355252