Main INDEX
Monthly INDEX
PREV
NEXT
User name Reitz
Log entry time 18:14:41 on July 6,2001
Entry number 65653
Followups:
keyword=Third TDC peak
The strange third TDC peak, which is related to events
of type T1, but without S1 and VDC, is probably caused
by some kind of cross-talk:
- in S2, panel 1 something causes a strong signal (on both
PMTs) . It is that big, that it drives the ADCs into saturation.
- the signal of those PMTs is connected to channel 9 of a Lecroy
discriminator
- these strong signals induce cross talk to channel 8, which is
nearly unused, (we only have six panels in S1 rs. S2), so it is not
connected to any ADC or TDC.
- but it is connected to the or over all panels. Where it produces
these ghost S1 signals, which are necessary to make a T1
=> for the time being, I've just disconnected the output of
channel 8 of the discriminators. so these peaks should
disapear. (looks fine on a scope, will check it with a cosmics run)
but nevertheless, in the long term, one might want
to get rid of those strong signals.