** Trigger simulation *** (see pdf file)

1 GeV muons have been simulated at 0, 10, 20, 30 and 40 degrees in zenith

and [0, 360] degrees in azimuth (uniform random distributed).

The input point is displaced of 1

cm in x and 1 cm in y from the center of the first ssd layer, and it is

Gauss distributed with a sigma of 1 mm (gaussian illumination across

several strips).

The time over threshold (1/4 mip) respect to the trigger time Tc has been

evaluated at strip level (T2-Tc in the figures).

The T2-Tc are greater than about 2 microseconds for all these

configurations. In other words, the trigger signal could go back to the

tracker in about 2 microseconds with about 100 % efficiency.

1 GeV muons have also been simulated at 40 degrees in zenith and 0 degrees

in azimuth. The T2-Tc distributions have been evaluated for odd

(continuos line) and for even ssd layers (dashed line), namely for the

strips oriented along the generated muon plane and for the strips oriented

orthogonal respect the generated muon plane. The T2-Tc are greater than

about 2 microseconds too.

Finally, the T2-Tc have been evaluated with a higher threshold (1/2 mip)

for 0 deg in zenith and [0, 360] degrees in azimuth (uniform random

distributed). The T2-Tc time is lower, and for 2 microseconds we have

about 90 % efficiency (last figures, continuos line: th=1/4 mip,

dashed line: th=1/2 mip).