FROM TH2F
constant
16.37085103480322+-0.5840029088115581
chi2/ndof = 62.97846708397877
plane
-21.74128777120869+-7.185133857102251
invpt slope = -3.1301358618826067+-0.415144221430812
theta slope = 37.60618455216458+-6.396652734991392
chi2/ndof = 64.50411770446672
from tgraph2D
constant
81.84193767263979+-6.133207165693939
chi2/ndof = 1918.427738238181
plane
167.20656383900914+-64.44689542545748
invpt slope = -12.711463405027292+-3.8538581527835793
theta slope = -45.99675707779852+-52.38936406760688
chi2/ndof = 1570.820295526916