1 {
2 TFile *
f =
new TFile(
"../hadron_track/pion/pion.root");
3 TTree *
t = (TTree*)
f->Get(
"n103");
4 TCanvas *c1 = new TCanvas("c1","dE/dx distribution",10,10,800,642);
5 t->Draw(
"dEdx_hit>>h(400, 0,3000)",
"ptrk>0.802 & ptrk<0.803",
"", 100000);
6 TArrow *a1 = new TArrow(1040.5, 50., 1040.5, 5., 0.02, "|>");
7 TArrow *a2 = new TArrow(1454.5, 50., 1454.5, 5., 0.02, "|>");
8 TArrow *a3 = new TArrow(1578.7, 50., 1578.7, 5., 0.02, "|>");
9 a1->Draw();
10 a2->Draw();
11 a3->Draw();
12 c1->SaveAs("figs/hist_illustration.eps");
13}
TFile f("ana_bhabha660a_dqa_mcPat_zy_old.root")