-- Installation of the Pre-Processor in the ATLAS Level-1 Calorimeter Trigger --
(links hereunder point to a picture
of the item; use the browser's "back" to return here)
All parts of the Pre-Processor System were produced during 2005/06 in the quantities required for the ATLAS experiment. Before this stage was reached, final prototypes ("Module_0") were tested thoroughly:
in a testbeam at the CERN-SPS, where real detector-elements exposed to beam-particles delivered analog signals as trigger-input.
Finally, peer-reviews gave "go-aheads" for the production. The approved prototype of a Pre-Processor Module consists of a 9u VME-motherboard and many rather complex daughter-boards.
The PPM-assemblies (motherboards fully equipped with daughterboards) were tested again at KIP in their final crate-configuration (16 PPMs). These tests verfied the environmental conditions like power-load, cooling of each board, transmssion of protocol-signals to each station in a fully installed ATLAS-crate.
The infrastructure in the "electronics barrack" next to the cavern housing the ATLAS-detector had been prepared. Cabling for analog signals from the ATLAS-calorimetry was laid already to the racks housing the trigger electronics. The Pre-Processor Modules in a crate literally disppear behind their input-cabling. Yet the LED-indicators in the center of a front-panel can just still be inspected.
Not only the input of 7200 analog calorimeter-signals presents high-density cabling at the front of the modules, but also the huge number of digital outputs to both trigger-processor systems (1. "Cluster processor", 2. "Jet/Energy Processor") requires careful planning of cable-logistics. Due to the high connector density, the miniaturisation and the high signal-speed (480 MBit/sec), the challenge is an even bigger one than on the input-side. The problems were, however, mastered.
After a long and difficult job done, the workers leave the building site. The completion is documented for purposes like this page here. Many in-situ tests are carried out to get the system into shape for ATLAS data acquisition. Beams in LHC are imminent (autumn 2008). The contribution of KIP in the shape of the "Pre-Processor system in the Level-1 Calorimeter Trigger" is ready to select the "interesting physics" for analysis.
Care was taken to complete the project NOT as outlined here, but to build the right thing for the purpose.
