Pixel response file with shield plane at 900V for ND-LAr

[jaafar-chakrani]

Summary

I'm adding here the pixel response file with shield plane. This file is obtained from Jiangmei's simulation at 900 V for the 2x2 drift length (~30 cm), and padded with zeros to match the ND-LAr drift length (~47 cm). This should be fine because the induced current between 30 and 50 cm is multiple magnitudes smaller in the shield-plane case (see bottom plot).

Validation

Values and shapes

import numpy as np

new_response = np.load('response_37_v2d_shield900V_fsd_ndlar_full.npz')

print("Response file w/ shield plane:")
print(" * Response shape: ", new_response['response'].shape)
print(" * Time tick: ", new_response['time_tick'])
print(" * Drift length: ", new_response['drift_length'])
print(" * Bin size: ", new_response['bin_size'])

old_response = np.load('response_37_v2d_fsd_ndlar_full.npz')

print("Response file w/o shield plane:")
print(" * Response shape: ", old_response['response'].shape)
print(" * Time tick: ", old_response['time_tick'])
print(" * Drift length: ", old_response['drift_length'])
print(" * Bin size: ", old_response['bin_size'])

Output:

Response file w/ shield plane:
 * Response shape:  (45, 45, 2975)
 * Time tick:  0.1
 * Drift length:  46.788
 * Bin size:  0.0372
Response file w/o shield plane:
 * Response shape:  (45, 45, 5950)
 * Time tick:  0.05
 * Drift length:  46.788
 * Bin size:  0.0372

Notice that the time tick in the with-shield file is 100 ns vs. 50 ns in the no-shield one, but this is taken care of properly in larnd-sim (e.g. here and here).

Induced current at different x, y positions

Region padded with zeros

[jaafar-chakrani]

Summarizing Dan's comment here: the suppression of the induced current at the far field (as shown in the last plot above) appears to be very high, probably due to idealized assumptions in the Garfield simulation, so it needs some additional thoughts/cross checks.