Experience with a Slow Control system based on industrial process control hardware and software for the XENON1T dark matter search

The XENON1T dark matter experiment

“…The system is protected by a firewall and only authorized users have the possibility to perform operations beyond data access, according to their pre-defined role. More details on the system are presented in [77].…”

“…The slow control system continuously monitors the state of all sub-systems' instruments and equipment. Its software and hardware architecture is identical to the successful XENON1T system [3,86]. It relies on industry-standard control hardware (PACs: programmable automation controllers) and software [87].…”

The XENON1T data acquisition system

“…The electronics of XENON1T are housed in a counting room within a service building adjacent to the water tank containing the detector [7]. PMT high voltage is controlled via the XENON1T slow control system [14] 90 MB/s. By parallelizing readout over multiple optical links and PCs, a maximum readout rate of 300 MB/s is achieved for the complete system, which is sufficient to record the 100 Hz target rate for the 220 Rn calibration mode.…”

“…Disruptions within the DAQ are also propagated to the slow control system over the API, and alarms are raised in the case of DAQ errors, loss of connectivity to the API, or if the data rate has been zero for an extended time. The slow control alarm system then alerts operators and experts via email and telephone [14].…”

The XENON1T Data Acquisition System

“…The electronics of XENON1T are housed in a counting room within a service building adjacent to the water tank containing the detector [7]. PMT high voltage is controlled via the XENON1T slow control system [14] and supplied by CAEN A1535N modules connected via custom-made passive low-pass filter boxes with a 2.8 MHz cutoff frequency to reduce electronic noise. The filter boxes reduce the RMS of the baseline from a mean of (0.91 ± 0.19) mV to (0.31 ± 0.06) mV, with the remaining dominant 25 kHz noise frequency originating from the high voltage power supplies themselves.…”