The AURIGA data acquisition
|After the last amplification stage, the output electric
signal of the detector is carried with a 20m long shielded coaxial cable
to a 23bit-10MHz ADC board on a VXI bus.
The ADC control is provided from the acquisition workstation by hardware Interrupt Requests (IRQ), which have a slow intrinsic time jitter of the order of 0.1Ás. Each time new data are ready in the ADC internal memory, an IRQ is sent from the ADC to the GPS clock, that answers back a synchronization time label to the acquisition workstation through an RS232 port. In this way the achieved timing precision is of the order of 0.1Ás.
The acquisition software collects the data from the ADC, add to them the time label, setup parameters and other informations organized in a binary frame. Then the frame can be stored on disk, stored on tape, sent by ethernet TCP to the analysis workstations or just used 'on the fly' by monitoring software.
The acquisition of the detector signal can be done along with auxiliary informations, e.g. from sysmometers, thermometers, analog lock-ins, and so on. These data are digitized with a multiplexed 24 channels 16bit ADC board, or acquired through the GPIB port. The latter port can provide control signals for instrumentations as well.
A photograph of the AURIGA data acquisition room. For a more detailed picture see fig. 11 of the AURIGA photo album