Tilecal Pion Response and Energy Resolution

Pion response vs. energy (1) News: bug-fix: original plot dealt with nominal beam energies on X-axis, whereas we should consider real beam energies effectively the only change is at 350 GeV (real E=333.5 GeV) no impact on results (e/h remains the same) use "average" transverse energy leakage corrections and assign the appropriate systematic error to e/h (comment by Ana) small effective change of e/h (from 1.356±0.013 to 1.352±0.013) same style as in TB paper: full circles = data open squares = MC

Pion response vs. energy (2) systematics is the half of the difference between the two leakage corrections this yields e/h = 1.352±0.013(stat)±0.005(sys)

Pion response vs. energy (3) why do we fix both parameters in the fit ? (comment by Tancredi) so far we fixed m=0.84 and E0=1 according to results obtained by Tancredi and Margar at 90 deg (they fix E0=1) let's try .... WHAT DO WE CHOOSE FOR THE PAPER ? really crazy makes sense, but lower e/h and of coarse much bigger error

Pion response vs. energy (4) We decided to have fit with two parameters free (result shown on previous page), what is the systematics associated with the two sets of transverse leakage corrections ? here the systematics is much bigger than in case of only 1 free parameter the result is thus: e/h = 1.33 ± 0.06(stat) ± 0.02(syst) m = 0.85 ± 0.03(stat) ± 0.008(syst)

Energy resolution (1) Baseline is what we currently have in the TB paper draft News: what is the impact of the noise, can we make the resolution fit with the noise term ? (comment received during Rio TW) noise is different in high- and low-gain, therefore the noise contribution depends on the beam energy (since one has to take into account the share of high- and low-gains in the total energy) one cannot simply add the noise term to the fit issue was studied in details with bi-gain pedestal runs (and using info from ordinary pion runs on the high/low-gain share) resulting noise is Gaussian-like; ranges from σ = 0.16 pC (20 GeV and below, all channels are high-gain) to σ = 0.86 pC (350 GeV) subtracting this noise in quadrature has absolutely no effect on the resulting resolution

Energy resolution (2) Proposal: leave the fit as it is and mention that noise has been carefully evaluated but is too small to affect the results. bug-fix: original plot dealt with nominal beam energies on X-axis, whereas we should consider real beam energies effectively the only change is at 350 GeV (real E=333.5 GeV) the fit basically does not change old: a=(52.7±0.9)% b=(5.7±0.2)% new: a=(52.9±0.9)% b=(5.7±0.2)%