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Z->ee data sample. Lee Pondrom 8 Oct 2012. First look at electron Stntuples. Fileset files events bhelbd 881 26 499 561 bhelbh 774 20 026 640 bhelbi 1829 40 529 045 bhelbj 1672 35 279 101 bhelbk 1873 37 161 882
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Z->ee data sample Lee Pondrom 8 Oct 2012
First look at electron Stntuples • Fileset files events • bhelbd 881 26 499 561 • bhelbh 774 20 026 640 • bhelbi 1829 40 529 045 • bhelbj 1672 35 279 101 • bhelbk 1873 37 161 882 • bhelap 19095 499 025 652 • 657 E6 total
Stntuple electron filesets • Typical electron fileset is 4X a large as a typical muon fileset. • Use of the CAF is essential. • Total number of Z->ee events ~250,000, matching the total Z->mumu. • Z->ee yield per fileset ~0.0004.
Electron quality cuts • Electromagnetic shower in the CEM plus matching charged track in the COT. • (z,φ) coordinates at radius of CES gives shower location. • ET>25 GeV • Had/Em < 0.055+0.00045*E • Isolation variable: (ET in CEM+CHA in cone of 0.4 around the electron shower, minus the ET of the electron shower)/eleET
Electron quality cuts • Cluster ET/track match pT<2.0 if pT<50GeV • Track pT is generally lower due to radiation • Lshr < 0.2. Lshare is a variable used by CDF since antiquity. It checks that the transverse shower development in the CEM is consistent with that expected from electromagnetic radiation.
Z->ee candidates • Require ET>25 GeV, ||<1, and the 4 quality cuts for electron #1. • Require ET>25 GeV, ||<1. for electron #2 • Require opposite charges.
conclusions • Z yield looks consistent for e’s and ’s. • Z-> mass resolution slightly better. No quality cuts have been made on ele#2. • Cutoff for Z->ee at low mass is from ET>25 GeV. • Look at the transtrack game next.