Burak Bilki (U)
The Phase I Upgrade of the CMS Hadron Endcap Calorimeters consist of new photodetectors (Silicon Photomultipliers in place of Hybrid Photo-Diodes ) and front-end electronics (QIE11). The upgrade will allow the elimination of the high amplitude noise and drifting response of the Hybrid Photo-Diodes, at the same time enabling the mitigation of the radiation damage of the scintillators and the wavelength shifting fibers with a larger spectral acceptance of the Silicon Photomultipliers. The upgrade will also allow to increase the longitudinal segmentation of the readout to be beneficial for pile-up mitigation and recalibration due to depth-dependent radiation damage. As a realistic operational exercise, the responses of the Hadron Endcap Calorimeter wedges are being calibrated with a 60Co radioactive source both with current and upgrade electronics. The exercise will provide a manifestation of the benefits of the upgrade. Here we describe the instrumentation details and the operational experiences related to the sourcing exercise.
Burak Bilki (U)
Alexander Kaminskiy (Moscow State University) Andrea Benaglia (Princeton University) Andrei Gribushin (Moscow State University) Caleb Smith (Baylor University) Danila Tlisov (Institute for Nuclear Research, Moscow, Russia) Ianos Schmidt (University of Iowa) Jay Dittmann (Baylor University) Joshua Kunkle (University of Maryland) Maria Toms (Institute for Theoretical and Experimental Physics, Moscow, Russia) Paolo Rumerio (University of Alabama) Pavel Bunin (Joint Institute for Nuclear Research) Pawel De Barbaro (University of Rochester) Seth Cooper (University of Alabama) Stepan Obraztsov (Moscow State University) Vladimir Andreev (P.N. Lebedev Physical Institute, Moscow, Russia)