10 Signal Processing for Particle Detectors
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Fig. 10.13 An illustration of noise contributions for both locations of white noise sources (series
and parallel) due to various segments of the weighting function. Such a piece-wise linear
approximation of the weighting function provides an estimate of the noise within a few percent
of accurately computed integrals I 1 and I 2
Fig. 10.14 An example of general behaviour of equivalent noise charge (ENC) as a function of
the width parameter τ of the weighting function. 1/f noise raises the noise minimum but does not
affect its position on the time scale
Eq. (10.4). This is illustrated in Fig. 10.14. From Eqs. (10.5, 10.6, and 10.8) the
optimum width parameter of the weighting function is given by,
τ opt =
R s R p
1/2 C in
A 1
A 3
1/2
,
(10.9)
and it is not affected by 1/f noise.