Standalone Geant4 and extra X0
one preshower of CsI (tracker+extra material)
and 8 layers of CsI (19.9mm)
look at the ratio of the mean energy in the merit
over the mean energy in the standalone MC for
each layer
how does it change when increasing the
preshower thickness ?
Ph. Bruel - BT-meeting - 22/11/2006 – p.1/10
CU simulation / G4 standalone
Tkr=1.5 X0
1.5
1.5
1.4
1.3
1.2
1.1
1.2
1.1
1.3
1.2
1.1
1.4
1.3
1.2
1.1
1
1
1
0.9
0.9
0.9
0.9
0.8
0.8
0.8
0.8
0.7
0.7
0.7
0.7
0.6
0.6
0.6
1
2
3
4
5
0.5
0
6
7
8
layer number
1
2
3
4
5
0.5
0
6
7
8
layer number
0.6
1
2
3
4
5
0.5
0
6
7
8
layer number
1
2
Tkr=1.8 X0
Tkr=1.9 X0
1.5
1.5
1.5
1.4
1.3
1.2
1.1
1.4
1.3
1.2
1.1
merit/csi mean energy
Tkr=1.7 X0
1.5
merit/csi mean energy
Tkr=1.6 X0
merit/csi mean energy
merit/csi mean energy
1.3
1.4
1
0.5
0
1.4
1.3
1.2
1.1
1
0.9
0.9
0.9
0.8
0.8
0.8
0.8
0.7
0.7
0.7
0.7
0.6
0.6
0.6
4
5
0.5
0
6
7
8
layer number
1
2
Tkr=2.0 X0
Tkr=2.1 X0
1.5
1.5
1.4
1.3
1.2
1.1
5
6
7
8
layer number
0.8
0.8
0.7
0.7
3
4
5
6
7
8
layer number
0.6
3
4
5
6
7
8
layer number
2
3
4
5
6
7
8
layer number
0.5
0
1
2
4
5
6
7
8
layer number
1.1
1
2
3
0.6
1
1.2
0.9
1
0.5
0
1.3
0.9
0.5
0
4
1.4
1
0.6
3
6
7
8
layer number
1.1
0.9
3
5
1.2
1
2
4
1.3
1
1
3
1.4
1
0.5
0
merit/csi mean energy
1.4
merit/csi mean energy
Tkr=1.4 X0
1.5
merit/csi mean energy
Tkr=1.3 X0
1.5
merit/csi mean energy
Tkr=1.2 X0
merit/csi mean energy
merit/csi mean energy
increasing the preshower thickness from 1.2 to 2.1 X0
0.5
0
Ph. Bruel - BT-meeting - 22/11/2006 – p.2/10
1
2
X0s upstream the cal in MC
In the CU simulation : tracker + extra material = 1.45 X0
slope
merit BT162 (MC 100 GeV)
0.06
0.04
0.02
0
-0.02
-0.04
-0.06
1.2
1.4
1.6
1.8
2
Tkr X0
Ph. Bruel - BT-meeting - 22/11/2006 – p.3/10
CU MC and 1.45 X0
merit BT162 (black) and standalone G4 with 1.45 X0 (red)
CalELayer0
hmerit_0
CalELayer1
Entries10386
0.16
Mean
650.6
RMS
320.1
0.16
Mean
1883
RMS
797.5
hmerit_2
hmerit_3
CalELayer3
Entries10389
0.14
Mean
3820
RMS
1351
Entries 10391
0.14
Mean
6075
RMS
1760
0.12
0.12
0.12
0.12
0.1
0.1
0.08
0.08
0.06
0.06
0.04
0.04
0.02
0.02
0.1
0.1
0.08
0.08
0.06
0.06
0.04
0.04
0.02
0.02
0
0
200 400 600 800 1000 1200 1400 1600
CalELayer4
hmerit_4
Mean
8073
RMS
1875
hmerit_5
0.16
Mean
9391
RMS
1709
0.12
0.1
0
0
1000 2000 3000 4000 5000 6000 7000 8000
CalELayer6
Entries10396
0.14
0.12
0
0
500 1000 1500 2000250030003500 40004500
CalELayer5
Entries10392
0.14
CalELayer2
0.14
0.14
0
0
hmerit_1
Entries10387
hmerit_6
CalELayer7
Entries 10401
0.18
Mean
9848
RMS
1383
2000
4000
6000
8000 10000 12000
hmerit_7
Entries10408
0.18
0.16
0.16
0.14
0.14
0.12
0.12
0.1
0.1
0.08
0.08
0.06
0.06
0.04
0.04
0.02
0.02
Mean
9377
RMS
1070
0.1
0.08
0.08
0.06
0.06
0.04
0.04
0.02
0.02
0
0
0
2000 4000 6000 8000 10000 12000 14000
0
0
2000 4000 6000 8000 1000012000 14000
0
0
2000 4000 6000 8000 10000 12000 14000
0
Ph. Bruel - BT-meeting - 22/11/2006 – p.4/10
2000 4000 6000 8000 10000 12000
CU MC and 1.45 X0
merit BT162 and standalone G4 with 1.45 X0
mean energy ratio (black) and RMS energy ratio (red)
merit/csi mean energy
merit/csi:layer
1.5
1.4
1.3
1.2
1.1
1
0.9
0.8
0.7
0.6
0.5
0
1
2
3
4
5
6
7
8
layer number
Ph. Bruel - BT-meeting - 22/11/2006 – p.5/10
CU data / G4 standalone
Tkr=1.5 X0
1.5
1.5
1.4
1.3
1.2
1.1
1.2
1.1
1.3
1.2
1.1
1.4
1.3
1.2
1.1
1
1
1
0.9
0.9
0.9
0.9
0.8
0.8
0.8
0.8
0.7
0.7
0.7
0.7
0.6
0.6
0.6
1
2
3
4
5
0.5
0
6
7
8
layer number
1
2
3
4
5
0.5
0
6
7
8
layer number
0.6
1
2
3
4
5
0.5
0
6
7
8
layer number
1
2
Tkr=1.8 X0
Tkr=1.9 X0
1.5
1.5
1.5
1.4
1.3
1.2
1.1
1.4
1.3
1.2
1.1
merit/csi mean energy
Tkr=1.7 X0
1.5
merit/csi mean energy
Tkr=1.6 X0
merit/csi mean energy
merit/csi mean energy
1.3
1.4
1
0.5
0
1.4
1.3
1.2
1.1
1
0.9
0.9
0.9
0.8
0.8
0.8
0.8
0.7
0.7
0.7
0.7
0.6
0.6
0.6
4
5
0.5
0
6
7
8
layer number
1
2
Tkr=2.0 X0
Tkr=2.1 X0
1.5
1.5
1.4
1.3
1.2
1.1
5
6
7
8
layer number
0.8
0.8
0.7
0.7
3
4
5
6
7
8
layer number
0.6
3
4
5
6
7
8
layer number
2
3
4
5
6
7
8
layer number
0.5
0
1
2
4
5
6
7
8
layer number
1.1
1
2
3
0.6
1
1.2
0.9
1
0.5
0
1.3
0.9
0.5
0
4
1.4
1
0.6
3
6
7
8
layer number
1.1
0.9
3
5
1.2
1
2
4
1.3
1
1
3
1.4
1
0.5
0
merit/csi mean energy
1.4
merit/csi mean energy
Tkr=1.4 X0
1.5
merit/csi mean energy
Tkr=1.3 X0
1.5
merit/csi mean energy
Tkr=1.2 X0
merit/csi mean energy
merit/csi mean energy
increasing the preshower thickness from 1.2 to 2.1 X0
0.5
0
Ph. Bruel - BT-meeting - 22/11/2006 – p.6/10
1
2
X0s upstream the cal in data
In the CU data : tracker + extra material = 1.55 X0
slope
merit 700002024 (100 GeV)
0.06
0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
1.2
1.4
1.6
1.8
2
Tkr X0
Ph. Bruel - BT-meeting - 22/11/2006 – p.7/10
CU data and 1.55 X0
merit 700002024 (black) and standalone G4 with 1.55 X0 (red)
CalELayer0
hmerit_0
hmerit_1
CalELayer1
Entries43366
0.18
Mean
805.3
RMS
375.4
0.16
CalELayer2
Entries43368
Mean
0.16
RMS
2263
hmerit_2
CalELayer3
Entries43368
0.16
927
Mean
4274
RMS
1494
hmerit_3
Entries43370
0.16
0.14
0.14
0.12
0.12
0.1
0.1
0.08
0.08
0.06
0.06
0.06
0.04
0.04
0.04
0.02
0.02
0.02
Mean
6931
RMS
2049
0.14
0.14
0.12
0.12
0.1
0.1
0.08
0.08
0.06
0.04
0.02
0
0 200 400 600 800 100012001400160018002000
CalELayer4
0
0
hmerit_4
1000
CalELayer5
2000
3000
4000
hmerit_5
Entries 43371
Entries
Mean
8688
Mean
RMS
2119
0.18
0
0
5000
RMS
CalELayer6
1969
0.2
RMS
2000 4000 6000 8000 10000 12000
CalELayer7
43380
hmerit_7
Entries
Mean 1.05e+04
1.034e+04
0.16
hmerit_6
Entries
43375
0
0
1000 20003000 4000 5000 6000 7000 80009000
43384
Mean 1.01e+04
1546
RMS
1298
0.2
0.16
0.14
0.14
0.15
0.12
0.15
0.12
0.1
0.1
0.1
0.08
0.1
0.08
0.06
0.06
0.04
0.02
0.05
0.02
0
0
0.05
0.04
0
2000 4000 6000 8000 100001200014000
0
0
2000 4000 6000 800010000120001400016000
0
0
2000 4000 6000 8000 100001200014000
0
Ph. Bruel - BT-meeting - 22/11/2006 – p.8/10
2000 4000 6000 8000 1000012000 14000
CU data and 1.55 X0
merit 700002024 and standalone G4 with 1.55 X0
mean energy ratio (black) and RMS energy ratio (red)
the mean energy ratio is almost constant ∼ 5%
merit/csi mean energy
merit/csi:layer
1.5
1.4
1.3
1.2
1.1
1
0.9
0.8
0.7
0.6
0.5
0
1
2
3
4
5
6
7
8
layer number
Ph. Bruel - BT-meeting - 22/11/2006 – p.9/10
Conclusion
The data/MC discrepancy for on-axis 100 GeV electrons can be explained by :
0.1 X0 extra material in front of CU (any idea ?)
a ∼ 5% miscalibration (bad nonlinearity correction because of beam conditions ?)
This scenario should be checked at :
other energies (at 10 GeV the discrepancy is
already constant and ∼ 5%...)
other angles (30 deg simulation is being produced)
Ph. Bruel - BT-meeting - 22/11/2006 – p.10/10