Until yet mainly a test setup consisting of scintillating counters and silicon PIN diodes is used to monitor the targets. In 1996 the technical test run for the HERA-B sub-detectors, the various triggers and the data acquisition has started. The prototype detector delivers until yet mainly information for improved diagnostic, here esp. the VDS is very helpful (cp. Fig. 16). In the future the HERA-B detector will provide detailed information about rates, the contributions of individual wires etc. , which will be used for steering.
The DAQ system consists mainly out of scalers. ADCs, TDCs and especially
a 40 MHz and 1 GHz FADC system provides detailed information e.g. on the
event topology, the timing and the contribution of individual bunches.
A large number of external data (HERA and other experiments etc.)
are read from various online data servers
and written into one common target online database.
The target information (mainly rates and wire positions)
is delivered through various servers
to the other HERA-B subcomponents, to HERA, the other HERA experiments
and is displayed online on the HERA WEB
page
.
The online monitoring is very essential, for the operation of the target
as well as for the coordination with other groups.
Already now usually at least 20 users request or display target informations.