Installation of the DCal, the second component of the ALICE Di-Jet calorimeter detector, was completed in late October 2014, two weeks ahead of its scheduled installation window. The DCal is situated in the ALICE central barrel, 180 degrees in azimuth from the EMCal, and completes the calorimetric coverage of the open regions of ALICE. This configuration enables back-to-back coincidence measurements of jets with various triggers, including jets, photons, and high momentum hadrons and electrons. The DCal thereby expands the ALICE jet program significantly.
The DCal structure, which is identical to that of the ALICE EMCal, is based on supermodules, each of which consists of 1100 individual calorimeter towers and weigh about 8 tons. The DCal is made up of six full-sized supermodules and two 1/3-sized supermodules.
Members of the DCal installation team in the ALICE detector. The recently completed DCal is hanging above their heads.
The DCal was not initially part of the EMCal project, but followed the successful completion of the EMCal project in 2011. The DCal effort required redesign of the ALICE support structure, fabrication and assembly of the DCal components, and finally, integration and installation of the full detector in ALICE.The success of this project is due to the great effort of many members of the collaboration and the ALICE Integration Team.