1 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Degrader 58 Ni Beam Fragments Target EM miniCAL GSI’s Fragment Separator (FRS) Cocktail beam at 1.7 GeV/nucleon

2 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status miniCAL: 8 layers of 3 logs each already used at CERN in august crystals from Kalmar, Saclay, Bordeaux CDEs made at Saclay (same as for EM) electronics: Bordeaux FRS trigger plastic Cocktail beam, 1.7 GeV/nucleon Minical

3 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status EM results Nhit Cocktail beam at 1.7 GeV/nucleon

4 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status This is not a bug: it’s a feature. Z-dependent position

5 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status There is a real bug in the EM trigger! Same number of events in two (FRS & EM) data streams External trigger worked fine. Did it? only about 40% of ions found in the peak in the first layer! Almost 80% for minical. 50% of events

6 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status FRS: calibration in Z, A miniCAL: - energy calibration: protons + charge injection - quenching factors - cross sections for charge-changing reactions EM - correction for non-linearity in EM electronics - energy calibration: - protons for LEX8 - cross calibration with real data for LEX1, HEX8, HEX1 - comparison with Sasha’s coefficients - quenching factors - cross sections for charge-changing reactions simulations (standalone GEANT4 v6.0): ionisation energy deposit for protons & ions Analysis Status (Bordeaux)

7 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Calculated energy deposit (taken from Thierry’ s note) SRIM-G4: 1% difference SRIM-G4: 10% for 1 mm 5% for 20 mm G4 may underestimate  E for protons Carbon Proton

8 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Position: X=6 Y=6 (run 165) blue: G4+broadening (0.65 MeV) black:data LEX8 absolute energy calibration with protons

9 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status HEX8/LEX1 Ratio LEX1 vs HEX8 X Y Cross calibration

10 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Comparison with Sasha’s coefficients Proton gain/muon gain Gain (MeV/channel) Layer

11 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Run 178 R L « X=6 Y=6 » but the alphas hit the Y=8 crystal! XY XY The Alpha run

12 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Protons and  do not hit at the same location. Correcting for this effect, the measured energy deposit for  is 9% (50.0 MeV instead of 45.9 MeV) too high as compared to the G4 predictions. Left vs Right amplitudes p  XY The Alpha run (2)

13 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Peak determination Z=14 Hit multiplicity

14 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Quenching For low Z ions, an « anti-quenching » effect (>20%) is observed.

15 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Quenching (2)

16 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status EM vs minical comparison 2% EM minical

17 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Comparison with calibration values established at CERN with 20 GeV muons Minical calibration coefficients

18 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Longitudinal shower profiles measured at CERN 50 GeV 1.3 X 0 80 GeV 1.3 X GeV 0 X GeV 4 X GeV 8 X 0

19 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Cross sections determination Ionisation peaks: « non-interacting » events

20 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status x: depth  : reaction cross section  : density P survival = exp(-x  ) Z=8 Z=14 Z=20 Z=26 minical Cross sections determination (2)

21 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Measured cross sections

22 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status « Things to be done » list Look into EM trigger problem Investigate effects of cuts Position studies Nuclear reactions studies (we have protons and alphas as well) And there are the great many runs using different conditions we have not looked at.

23 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status

24 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status FRS ion identification

25 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Non-linearity manifests the quenching effect! MiniCAL results Cocktail beam at 1.7 GeV/nucleon

26 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status MiniCAL absolute-energy calibration

27 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status EM results Cocktail beam at 1.7 GeV/nucleon

28 GLAST LAT Project CalSoft Face-to-Face Meeting April 15 – 16, 2004 Benoît Lott GSI Analysis Status Hit distribution