Minutes

RC:

slides - "EM sampling fracctions from photons"

RC: Presenting sampling fractions.

Single photons, 1-10 GeV, uniform in angle. Required conversion in first 1/2 of EM. Angle cuts in barrel, 45 deg, and endcap, away from edge. (don't remember exactly) Fit for sampling fraction.

Plotting total E in EMCal vs. Generated Energy.

Errors w/ estimate of sampling fraction. Iterate. Do a straight line fit.

Using sid00 detector.

Can do a fit. Not a bad chi-squared, assuming 20%/sqrt(E).

Repeat for endcaps w/ same procedure for 2 other EMCal calorimeters.

In cdcaug05 and sid00, compute sampling fraction doubling the energy from the last 10 layers.

RF: Standard cutoff?

RC: slic-generated with "standard" settings. Effective cutoff parameter is large.

RF: This is why 20% instead of 15%?

RC: Yes.

For sidaug05, cdcaug05, check against ZZ data. Plot the residuals.

Go through data and pick out photons. Pick out residuals. Fit with a Guassian. Mean close to 0. Sigma close to 1. Same thing for endcap. Not perfect, but close.

See slides for results.

Propose to put in as sampling fractions.

WL: Error?

RC: Error on the fit is small, in 4th or 5th decimal place.

Averages over a lot of stuff.

Should use same technique to obtain the number for all detectors.

MR: What does "corrected" mean?

RC: "Corrected" means that last 10 layers get weight x2.

Any objections get to me before tomorrow, will consider, but plan to put the numbers in for now.

RF: Did x2 with EGCS, and seemed to be the best.

RC: Seemed best to me.