July 10, 2001 LArg Meeting 1

Electronic Simulation Work at Victoria and TRIUMF

Victoria: Erica Muzzerall, Dr. Richard Keeler TRIUMF: Dr. Chris Oram

July 10, 2001 LArg Meeting 2

Outline Catch up on test beam simulation

NIM paper, Leonid Examine non-ideal signal source Conclusion

July 10, 2001 LArg Meeting 3

Leonid’s HEC Chain

July 10, 2001 LArg Meeting 4

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July 10, 2001 LArg Meeting 5

HEC Electronics Chain

July 10, 2001 LArg Meeting 6

Calibration Chain

July 10, 2001 LArg Meeting 7

Cold Electronics

July 10, 2001 LArg Meeting 8

Warm Electronics

July 10, 2001 LArg Meeting 9

HEC Chain Output

Left: fig 8 from HEC Note 109Right: our PSpice output

July 10, 2001 LArg Meeting 10

Non Ideal Signal Source

Fig 19, NIM paper

July 10, 2001 LArg Meeting 11

Hypothesis: Why these residuals? Consider 2 possible sources:

Unequal Liquid Argon gaps in EST Uncertainty in the gap capacitances

Future: Investigate cross talk

July 10, 2001 LArg Meeting 12

EST Drawing

July 10, 2001 LArg Meeting 13

Gap Tolerance

0

5

10

15

20

25

30

35

40

45

0 10 20 30 40 50 60

0.01 m m

Nu

mb

er

Measured difference in height between 8.5 m m copper plate spacer and gap m aterials

( 4 honeycom b + 2 EST + 1 Pad ).Under the pressure of 25m m of Copper

July 10, 2001 LArg Meeting 14

Model EST

Drift Times:400 V: 905 ns

1800 V: 548 ns

July 10, 2001 LArg Meeting 15

Ideal Shaper

July 10, 2001 LArg Meeting 16

Output from Perfect EST

V = 400 V

V = 1800 V

July 10, 2001 LArg Meeting 17

Modified Model EST

A B B B

A B

400 V

1029 ns

864 ns

1800 V

624 ns

524 ns

Drift Times:

July 10, 2001 LArg Meeting 18

Output from Modified Model EST

V = 400 V

red: ideal EST green: modified EST Gap change = 0.2 mm

V = 1800 V

July 10, 2001 LArg Meeting 19

Procedure Gap change was adjusted to approximate peak

height at end of NIM residual spectra 400 V : 0.055 mm 1800 V: 0.076 mm

The capacitance of ideal circuit was altered to approximate distortions at the beginning of NIM residual spectra

Ideal capacitance changed from 100 pf to 99 pf

July 10, 2001 LArg Meeting 20

Procedure

Td takes into account E-field change

July 10, 2001 LArg Meeting 21

ResultsV = 400 V V = 1800 V

July 10, 2001 LArg Meeting 22

Results – realistic shaper

July 10, 2001 LArg Meeting 23

Conclusion The investigated effects are a

plausible source of the observed residuals between the data and the nominal model.

Future: Investigate cross talk