Jiskefet, a bookkeeping application for ALICE

A new bookkeeping system called Jiskefet is being developed for A Large Ion Collider Experiment (ALICE) during Long Shutdown 2, to be in production until the end of LHC Run 4 (2029). Jiskefet unifies two functionalities: a) gathering, storing and presenting metadata associated with the operations of the ALICE experiment and b) tracking the asynchronous processing of the physics data. It will replace the existing ALICE Electronic Logbook and AliMonitor, allowing for a technology refresh and the inclusion of new features based on the experience collected during Run 1 and Run 2. The front end leverages web technologies much in use nowadays such as TypeScript and NodeJS and is adaptive to various clients such as tablets, mobile devices and other screens. The back end includes an OpenAPI specification based REST API and a relational database. This paper will describe the organization of the work done by various student teams who work on Jiskefet in sequential and parallel semesters and how continuity is guaranteed by using guidelines on coding, documentation and development. It will also describe the current status of the development, the initial experience in detector stand-alone commissioning setups and the future plans.

Multiplicity Dependence of Heavy-Flavour Hadron Decay Electron Production in Collisions at √sNN = 8.16 Measured with ALICE at the LHC

A Large Ion Collider Experiment (ALICE) at the Large Hadron collider (LHC) is a heavy-ion dedicated experiment designed to study nuclear matter at extreme condition of high temperature and high density at which quarks are deconfined and give rise to a new state of matter known as Quark Gluon Plasma (QGP). Heavy flavours (charm and beauty), are produced in the initial stages of hadronic collisions in hard scattering processes and therefore are effective probes to study the QGP. In this contribution, recent measurements of the production of electrons from heavy-flavour hadron decays, their nuclear modification factor and the self-normalised yield measured up to 14 in collisions at √sNN = 8.16 TeV collected in LHC Run2 in 2016 are presented.

Readout Software for the Alice Integrated Online-Offline (O2) System

ALICE (A Large Ion Collider Experiment) is a heavy -ion detector studying the physics of strongly interacting matter and the quarkgluon plasma at CERN’s LHC (Large Hadron Collider). During the second long shutdown of the LHC, the ALICE detector will be upgraded to cope with an interaction rate of 50 kHz in Pb–Pb collisions, producing in the online computing system (O2) a sustained input throughput of 3 TB/s. The readout software is in charge of the first step of data-acquisition, handling the data transferred from over 8000 detector links to PC memory by dedicated PCI boards, formatting and buffering incoming traffic until sent to the next components in the processing pipeline. On the 250 readout nodes where it runs, the software has to sustain a throughput which can locally exceed 100 Gb/s. We present the modular design used to cope with various data sources (hardware devices and software emulators), integrated with the central O2 components (logging, configuration, monitoring, data sampling, transport) and initiating the online data flow using the standard O2 messaging system. Performance considerations and measurements are also discussed.

GEM Foil Quality Assurance For The ALICE TPC Upgrade

The ALICE (A Large Ion Collider Experiment) experiment at the Large Hadron Collider (LHC) at CERN is dedicated to heavy ion physics to explore the structure of strongly interacting matter. The Time Projection Chamber (TPC) of ALICE is a tracking detector located in the central region of the experiment. It offers excellent tracking capabilities as well as particle identification. After the second long shutdown (LS2) the LHC will run at substantially higher luminosities. To be able to increase the data acquisition rate by a factor of 100, the ALICE TPC experiment has to replace the Multi-Wire Proportional Chamber (MWPC) –based readout chambers. The MWPC are operated with gating grid that limits the rate to O(kHz). The new ReadOut Chamber (ROC) design is based on Gas Electron Multiplier (GEM) technology operating in continuous mode. The current GEM productions scheme foresees the production of more than 800 GEM foils of different types. To fulfill the requirements on the performance of the GEM TPC readout, necessitates thorough Quality Assurance (QA) measures. The QA scheme, developed by the ALICE collaboration, will be presented in detail.

A MOdular System for Acquisition, Interface and Control (MOSAIC) of detectors and their related electronics for high energy physics experiment

In this work the MOSAIC (“MOdular System for Acquisition, Interface and Control”) board, designed for the readout and testing of the pixel modules for the silicon tracker upgrade of the ALICE (A Large Ion Collider Experiment) experiment at teh CERN LHC, is described. It is based on an Artix7 Field Programmable Gate Array device by Xilinx and is compliant with the six unit “Versa Modular Eurocard” standard (6U-VME) for easy housing in a standard VMEbus crate from which it takes only power supplies and cooling.

QUARKONIA MEASUREMENTS WITH THE CENTRAL DETECTORS OF ALICE

A Large Ion Collider Experiment – ALICE will become operational with the startup of the Large Hadron Collider – LHC at the end of 2007. One focus of the physics program is the measurement of quarkonia in proton-proton and lead-lead collisions. Quarkonia states will be measured in two kinematic regions and channels: di-muonic decays will be measured in the forward region by the muon arm, the central part of the detector will measure di-electronic decays. The presented studies show the expected performance of the di-electron measurement in proton-proton and central lead-lead collisions.