1. Progress on PID studies Rikard Sandström University of Geneva 2007-02-06 MICE Analysis meeting

2. Outline Probability continued TDC threshold and performance Reconstruction and PID Obstacles on the roadmap to PID size study MICE note(s)

3. Probability continued The signal efficiency is e s =∫ Out0 inf s(x)dx. The mutually exclusive probability is P s (x 0 <x<x 1 )=∫ x0 x1 s(x)/(s(x)+b(x))dx and integration limits (bin size) is chosen so that s(x)+b(x) constant.

4. TDC threshold and performance Many poorly identified muons are decaying in the open gate of the calorimeter, and the tdc cannot distinguish two separate peaks. –Make threshold higher! 83% of distribution has dE/dx>2 MeV/cm in polystyrene, which corresponds to 1.84 pC/cm at the highest point of the q(t) curve. -> New TDC threshold = 1.84 pC (independent of layer thickness). –Thinnest layer is 1 cm, but around Bragg peak dE/dx is higher. Waiting to see how this translates in PID performance.

5. Reconstruction and PID Before Christmas, I added the EMCal reconstruction in the Recon area, and PidFits in the Config area. This should make it very simple to read in NN weight files and assign PID quantities (“muonness”) to the events. Unfortunately I cannot read in any files right now from G4MICE, so I have not been able to work on that, but if I cannot finish this before I have to go it should not be a hard task for someone else.

6. Obstacles I have not run the simulation in quite some time and encountered new problems when I did run it recently: –Impossible to read in any simulated data, either for digitization or just make plots. –I have tried the Matcher application to get matched beams, but it failed. –The way we interfaced external magnetic field maps in G4MICE has changed, so I am now trying to understand how to do it. –Problems with production threshold of secondary particles and perhaps physics processes too. All of this I am sure the software group can solve, hopefully in time before the collaboration meeting. –Previous problem with cryostat disabling SciFi hits is solved.

7. MICE note(s) I am writing a summary of the PID analysis as a MICE note. It will contain all you need to know to understand how it works, what values are used and the performance obtained. A unpublished MICE note on expected time of flight is on my desk; in order to understand where those values comes from in the analysis MICE note, it might have to be included, or posted as a stand alone note.

8. Future plans After the CM in two weeks at CERN I will not have any time to work on MICE, so I am working hard to finalize PID results and write MICE notes, and to study the downstream detector sizes. –Whatever is not finished by then will not be finished. Do not expect any updates on anything from March onward.