The CMS ECAL Detector Control System

The challenging constraints on the design of the Electromagnetic Calorimeter (ECAL) of the Compact Muon Solenoid (CMS) experiment, such as rigorous temperature and voltage stability, imposed the development of a complex Detector Control System (DCS). In this paper the final layout and functionality of the CMS ECAL DCS are presented and the operational experience during the detector's commissioning and cosmic runs is discussed

The CMS ECAL Control and Safety Systems Upgrades during the CERN LHC Long Shutdown 2

The Electromagnetic Calorimeter (ECAL) is one of the sub-detectors of the Compact Muon Solenoid (CMS), a general-purpose particle detector at the CERN Large Hadron Collider (LHC). The CMS ECAL Detector Control System (DCS) and the CMS ECAL Safety System (ESS) have supported the detector operations and ensured the detectors integrity since the CMS commissioning phase, more than 10 years ago. Over this long period, several changes to both systems were necessary to keep them in-line with current hardware technologies and the evolution of software platforms. The acquired experience of long-term running of both systems led to the need of major modifications to the original design and implementation methods. Such interventions to either systems, which require mid- to long-term validation, result in a considerable amount of downtime and therefore can only be performed during long LHC shutdown periods. This paper discusses the software and hardware upgrades to be carried out during the LHC Long Shutdown 2 (LS2), with emphasis on the evaluation of design choices concerning custom and standard industrial hardware

Detector Control System for the electromagnetic calorimeter in the CMS experiment summary of the first operational experience

A full scale implementation of the Detector Control System (DCS) for the electromagnetic calorimeter (ECAL) in the CMS experiment is presented. The operational experience from the ECAL commissioning at the CMS experimental cavern and from the first ECAL and global CMS data taking runs is discussed and summarized

Status report on the architecture and future upgrades of the CMS Electromagnetic Calorimeter Control and Safety Systems

The Electromagnetic Calorimeter (ECAL) is one of the sub-detectors of the Compact Muon Solenoid (CMS) experiment of the Large Hadron Collider (LHC) at CERN. For more than ten years, the ECAL Detector Control System (DCS) and the ECAL Safety System (ESS) have supported the experiment operation, contributing to its high availability and safety. The evolution of both systems to fulfill new requirements and constraints, in addition to optimizations towards improving usage and process automation, led to several changes to their original design. This paper presents the current software/hardware architecture of both CMS ECAL DCS and ESS and reviews the major changes applied to both systems during the past years. Furthermore, in view of the CMS Phase-II upgrade of this sub-detector, the corresponding plans for the control and safety systems are also discussed

The CMS Electromagnetic Calorimeter Detector Control System

This paper presents the Detector Control System (DCS) designed and implemented for the Electromagnetic Calorimeter (ECAL) of the Compact Muon Solenoid (CMS) experiment at CERN. The focus is on its distributed controls software architecture, the deployment of the application into production and its integration into the overall CMS DCS. The knowledge acquired from operational issues during the detector commissioning and the first phase of the Large Hadron Collider (LHC) physics runs is discussed and future improvements are presented

Improving the Compact Muon Solenoid Electromagnetic Calorimeter control and safety systems for the Large Hadron Collider Run 2

The first long shutdown of the Large Hadron Collider (LS1, 2013-2015) provided an opportunity for significant upgrades of the detector control and safety systems of the CMS Electromagnetic Calorimeter. A thorough evaluation was undertaken, building upon experience acquired during several years of detector operations. Substantial improvements were made to the monitoring systems in order to extend readout ranges and provide improved monitoring precision and data reliability. Additional remotely controlled hardware devices and automatic software routines were implemented to optimize the detector recovery time in the case of failures. The safety system was prepared in order to guarantee full support for both commercial off-the-shelf and custom hardware components throughout the next accelerator running period. The software applications were modified to operate on redundant host servers, to fulfil new requirements of the experiment. User interface extensions were also added to provide a more complete overview of the control system. This paper summarises the motivation, design, implementation and validation of the major improvements made to the hardware and software components during LS1

Strategies and performance of the CMS silicon tracker alignment during LHC Run 2

The strategies for and the performance of the CMS silicon tracking system alignment during the 2015-2018 data-taking period of the LHC are described. The alignment procedures during and after data taking are explained. Alignment scenarios are also derived for use in the simulation of the detector response. Systematic effects, related to intrinsic symmetries of the alignment task or to external constraints, are discussed and illustrated for different scenarios.ISSN:0168-9002ISSN:1872-957

The CMS Barrel Calorimeter Response to Particle Beams from 2 to 350 GeV/c

The response of the CMS barrel calorimeter (electromagnetic plus hadronic) to hadrons, electrons and muons over a wide momentum range from 2 to 350 GeV/c has been measured. To our knowledge, this is the widest range of momenta in which any calorimeter system has been studied. These tests, carried out at the H2 beam-line at CERN, provide a wealth of information, especially at low energies. The analysis of the differences in calorimeter response to charged pions, kaons, protons and antiprotons and a detailed discussion of the underlying phenomena are presented. We also show techniques that apply corrections to the signals from the considerably different electromagnetic (EB) and hadronic (HB) barrel calorimeters in reconstructing the energies of hadrons. Above 5 GeV/c, these corrections improve the energy resolution of the combined system where the stochastic term equals 84.7$\pm$1.6$\%$ and the constant term is 7.4$\pm$0.8$\%$. The corrected mean response remains constant within 1.3$\%$ rms

Precision measurement of the structure of the CMS inner tracking system using nuclear interactions

The structure of the CMS inner tracking system has been studied using nuclear interactions of hadrons striking its material. Data from proton-proton collisions at a center-of-mass energy of 13 TeV recorded in 2015 at the LHC are used to reconstruct millions of secondary vertices from these nuclear interactions. Precise positions of the beam pipe and the inner tracking system elements, such as the pixel detector support tube, and barrel pixel detector inner shield and support rails, are determined using these vertices. These measurements are important for detector simulations, detector upgrades, and to identify any changes in the positions of inactive elements