10/14/20051 Tau reconstruction and H/A →  H/A →  MC events: PYTHIA ⇒ OSCAR ⇒ DIGI (mass 120 GeV ?) 10k events overnight DIGI ⇒ DST: crashes DIGI ⇒ Exroot: crashes after few events: ran 20 events at a time 4200 events in EXroot tree.

10/14/20052

3

4

5 Tau mass Calculation Use tau tagged jets with a single track (  →  n  0,l) Add energy in ECAL and HCAL cells within 0.25 of jet axis exclude cells 0.02 (ECAL)/0.09 (HCAL) from track Calculate the momentum of photons Add track momentum and energy Calculate invariant mass

10/14/20056 Reconstructed tau mass from generator e/p of tau decay particles except neutrinos.

10/14/20057 From CMS note Tagged tau jet Invariant mass

10/14/20058 Assuming the track electron/pion has negligible effect. Electron pion

10/14/20059

10

10/14/ (From Simone Gennai’s April CPT talk) Calculate  energy, momentum in collinear approx. add to the visible e/p to get mass.

10/14/200512

10/14/  mass from generator momentum and energy of  s Reconstructed 2  mass Use energies of s to get E T Use e/p of other tau decay particles as jet/track energy

10/14/ From Simone’s April talk