2-nd look on J/ψand 1-st iteration with vertex fitter

E. ShulgaNRNU “MEPhI”

2

J/ψ Selection Cuts

• pμT > 3 GeV;

• At least 1 μ is tight;• d0,z0 < 10;• Χ2/ndof<10;• BL Hits > 0• pJ/ψ

T > 6 GeVOpposite Sign Same sign

No Cuts 14745 28437

1 Tight Muon 14391 18470

1 MU4 trig. muon 12203 12382

d0, z0 < 10 11610 10357

Χ2/ndof<10 8544 2924

BL cut 8498 2910

pJ/ψT > 6 GeV 8483 2850

3

J/ψ Peak

- For vertex finding Tracking/TrkVertexFitter/TrkVKalVrtCore was used, and this is the first reasonable iteration with this tool;

- Vertex cuts will be applied

4

Summary & Plans• Selection cuts seams to be reasonable, some improvements

can be achieved taking Barrel and EndCap separately, and using MC;

• Finally there is a separation of prompt/non-prompt pairs, which have to be checked more carefully;

Plans:• Non-/prompt pairs have to be studied carefully ;• Start to look on MC ;• Main goal is to extract Rcp, so it will be one of the next steps;…