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IPPOG Newsletter #6
No full text6th IPPOG Newsletter, sent on 22 September 2025. Features: Spotlight on Conferences 2025, Save the Date(s), Beamline for Schools, Don’t Miss Out
Architecting software applications in containerized environment for CMS data acquisition
No full textThe data acquisition (DAQ) system stands as an essential component within the CMS experiment at CERN. It relies on a large network system of computers with demanding requirements on control, monitoring, configuration and high throughput communication. Furthermore, the DAQ system must accommodate various application scenarios, such as interfacing with external systems, accessing custom electronics devices for data readout, and event building. We present a versatile and highly modular programmable C++ framework designed for crafting applications tailored to various needs, facilitating development through the composition and integration of modules to achieve the desired DAQ capabilities. This framework takes advantage of reusable components and readily available off-the-shelf technologies. Applications are structured to seamlessly integrate into a containerized ecosystem, where the hierarchy of components and their aggregation is specified to form the final deployable unit to be used across multiple computers or nodes within an orchestrating environment. The utilization of the framework, along with the containerization of applications, enables coping with the complexity of implementing the CMS DAQ system by providing standardized structures and components to achieve a uniform and consistent architecture
Advancements and Operations for LHC Run-3 and beyond
No full textThis paper presents recent advancements in the EOS project– the large-scale data storage system developed at CERN–during the preparation and execution of LHC Run-3. Key developments include further simplification of the service architecture, enhancements to metadata performance, and the introduction of new storage device inventory and cost/value interfaces. Additionally, we introduce a new scheduler implementation, a generated REST API derived from the gRPC protocol, and improved integration of features such as SciTags and SciTokens. We report on operational experiences, including the large-scale migration from CentOS 7 to AlmaLinux 9 across over 1000 storage nodes, and significant improvements in EOS file system check (fsck) for erasure coded files.Looking ahead to Run-4 and the High-Luminosity LHC (HL-LHC) era, we outline the planned evolution of EOS, including ongoing software R&D; and storage technology evaluations. We discuss performance testing of hard disks using shingled magnetic recording (SMR) technology, the projected HDD capacity roadmap toward 50TB drives by 2030, and the potential role of SSDs in addressing storage performance challenges at CERN and beyond
Design of the OpenSkyLab project area and plots: reusing molasse excavation materials as functional soils for targeted plant-soil applications
No full textThe OpenSkyLab demonstrates on-site recycling of inert rock materials from tunneling activities into functional soils, tracks their evolution over time, and compares their performance across various potential uses. The scheme illustrates the spatial arrangement of the plots installed in the OpenSkyLab (Cessy, France), how they are constructed with different substrate layers and the plants used in the growth period 2025
Low-latency AI for triggering on electrons at High Luminosity LHC with the CMS Level-1 hardware Trigger
No full textIn preparation for the High Luminosity LHC (HL-LHC) run, the CMS collaboration is working on an ambitious upgrade project for the first stage of its online selection system: the Level-1 Trigger. The upgraded system will use powerful field-programmable gate arrays (FPGA) processors connected by a high-bandwidth network of optical fibers. The new system will access highly granular calorimeter information and online tracking: their combination for identifying physics objects is a key asset to cope with the harsh HL-LHC environment without compromising physics acceptance. The track matching is particularly relevant for identifying calorimeter deposits originating from electron particles. Traditional identification techniques rely on several independent selection stages applied to the calorimeter and track primitives, followed by an angular matching procedure. A new machine learning approach is presented, combining track and calorimeter information into a single identification and matching step. The new algorithm leverages new technologies for running fast inference on FPGA
Recent B-Physics Results from ATLAS
No full textStudying heavy-flavor hadron properties tests QCD predictions and provides a means to probe the Standard Model's validity. The ATLAS experiment, a general-purpose detector at the LHC, is particularly successful in such measurements with final states involving muons, due to large collected integrated luminosity and precise muon reconstruction and triggering. This paper overviews recent ATLAS results on b hadron production and decay properties and the spectroscopy of exotic states
Projected sensitivity for non-resonant production of vector leptoquarks and single production of vector-like quarks in final states with b-jets with the ATLAS experiment at the HL-LHC
No full textProjected sensitivity for -channel vector leptoquark in final states with -jets, and single-production vector-like quark (VLT) decaying to , using the ATLAS experiment at the High Luminosity LHC (HL-LHC) is presented: obtained from the extrapolation of analyses from the Run 2 dataset, using 140 of data at TeV. Two scenarios for the systematic uncertainties are taken into account. The baseline scenario assumes that the systematic uncertainties are reduced by taking into account the increased amount of data, while the Run 2 scenario assumes the same systematic uncertainties as used in the Run 2 analysis. For the leptoquark, the expected limit on using baseline (Run 2) scenario of systematic uncertainty improves about 30% (20%) and 40% (20%) for the case of 3 and 6 , respectively. For the VLT at 3 , the limit on at a given mass improves significantly, being reduced by about 30% at 1.2 TeV up to about 60% at 2.3 TeV, with only modest additional gains achievable through further improvements in systematics or the use of the full 6 dataset. The range of masses that can be studied within the constraints of the narrow-width approximation is extended from 2.3 TeV to over 2.7 TeV
Measurements of top quark properties in CMS: \ensuremath{t\overline{t}}~spin density matrix, quantum entanglement and quantum magic
No full textPolarization and spin correlation measurements of top quark-antiquark (\ensuremath{t\overline{t}}) pairs provide tests of the standard model, but also new ways to test quantum mechanics with unstable particles at highest energies ever produced in a laboratory.
Recent \ensuremath{t\overline{t}}~spin correlation measurements and the tests they enable, made with the CMS detector at the CERN LHC Run 2, are presented. The measurements summarized include the full spin density matrix measurement of top quark pairs using events with a single lepton and jets in the final state.
Spin correlation measurements in specific phase space regions allow the observation of the entanglement phenomenon, and the measurement of quantum magic.
From the measured spin correlation at the \ensuremath{t\overline{t}}~production threshold and high \ensuremath{t\overline{t}}~mass, entanglement is observed with a large fraction of the \ensuremath{t\overline{t}}~decays being spacelike separated. The observation of entanglement in \ensuremath{t\overline{t}}~events with two high transverse momentum leptons of opposite charge is also presented. Finally, the first TeV-scale experimental measurement of quantum magic, an important variable for the characterization of quantum states in quantum information science, is presented. These measurements provide one of the first connections between quantum information science and particle physics, and show the potential of collider experiments in the studies of the foundations of quantum mechanics