515664 research outputs found
Sort by
Luminosity measurements at CMS using DT Phase 2 Demonstrator
No full textIn Phase-2, CMS will rely on multiple detector systems and, in particular, DT Luminosity, this is the Synchronous histogramming of muon trigger primitives. In this phase hits from DT and RPC detectors will be combined to reconstruct muon track segments. The demonstrator system is equipped with 5 back-end boards. This report shows an analysis of several datasets recorded in 2023. Most of the analysis was performed for Fill 9062 (Stable Beams, 2452 colliding bunches). Background contributions such as type1 afterglow hits, cosmic and beam induced were analysed. Finally, the luminosity for one of the boards was computed
Significance of Corrosion Phenomena for Magnets of Accelerators, Fusion and High Energy Physics Experiments
No full textAlthough superconducting accelerator and fusion magnets operate at cryogenic temperature and in most cryogenic applications corrosion is not an issue, it is essential to avoid corrosion phenomena that may occur during production and fabrication of parts and components of magnet systems, or during their installation, assembly or maintenance. A delayed leak or a structural failure that would arise in operation due to onset of corrosion phenomena at an earlier stage could lead to grave consequences due to many such components becoming embedded and virtually unrepairable. Therefore, corrosion prevention is of paramount importance in all the phases of a project involving superconducting or even normal conducting magnets and their vacuum systems, including during storage of components or assemblies before their final commissioning and operation, in order to minimise the associated risks and guarantee their reliability over time. The return from decades of experience in assessing and investigating magnet components and ancillaries, and in analysing their failures is presented, showing the relevance and variety of corrosion phenomena that may affect magnet systems of accelerators, high energy physics experiments and fusion devices and their ancillaries. Through the examples and the failure analyses provided, the paper discusses the most relevant corrosion mechanisms, their prevention and applicable remediation actions, that have been of paramount importance for a reliable operation of the magnet systems
High Field Cos-Theta FalconD-C Dipole Magnet Development at CERN
No full textThe FalconD (Future Accelerator post-LHC Cos- θ Optimized Nb3Sn Dipole magnet is part of the High Field Magnet (HFM) CERN programme. In collaboration with the Ital- ian Institute for Nuclear Physics (INFN Genova and LASA Milano), CERN is developing a cos θ dipole magnet beyond 12 T based on proven Nb3Sn technology in the MQXF quadrupole used in the high-luminosity upgrade of the LHC. The magnet, with design aperture diameter of 50 mm, provides a bore field of 12 T for a 73 TeV center-of-mass energy scenario for the Future FCC-hh Circular Collider. The project has specific objectives to investigate cos-θ short magnet model design based on a two-layers coil with a wide high current cable. Moreover, the study of mechanical dipole structures based on aluminum shell with bladders and key (B&K) developed for the HL-LHC MQXF quadrupole will be presented as a baseline. The structure pre-loading system assembly baseline shall be tested on sub-scale mechanical mock ups at 77 K prior to building two single aperture 1.5 m long Nb3Sn magnet models fol- lowed by a 2-in-1 dipole magnet assembly. In this paper, we provide an overview of the magnetic and structural design carried out at CERN on an increased aperture diameter variant supported by first preliminary winding trials and give insights of the project timeline. Some preliminary protection scheme assessment is presented as baseline to be tested. Following the cable winding outcomes and the mechanical properties measured, some alternative coil optimized magnetic cross-section is reported
First measurement in nucleus-nucleus collisions at SPS energies with NA61/SHINE
No full textThe measurement of open charm meson production provides a tool for the investigation of the properties of the hot and dense matter created in nucleus-nucleus collisions at relativistic energies. In particular, charm mesons are of vivid interest in the context of the study of the nature of the phasetransition between confined hadronic matter and the quark-gluon plasma. Recently, the NA61/SHINE experimental setup was upgraded with a high spatial resolution Vertex Detector which enables the reconstruction of secondary vertices from open charm meson decays.The first direct neutral D meson yields at the SPS energy regime will be shown. The analysis used the 20% most central Xe+La collisions at 150A GeV/c from the data set collected in 2017. It allowed the estimation of the mid-rapidity yields (dN/dy) of D0 + D¯0 using their π± + K∓ decay channels and phase space corrections derived from the three models AMPT, PHSD, and PYTHIA/Angantyr. The results will be compared and discussed in the context of several model calculations including statistical and dynamical approaches.The measurement of open charm meson production provides a tool for the investigation of the properties of the hot and dense matter created in nucleus-nucleus collisions at relativistic energies. In particular, charm mesons are of vivid interest in the context of the study of the nature of the phase-transition between confined hadronic matter and the quark-gluon plasma. Recently, the experimental setup of the NA61/SHINE experiment was upgraded with the high spatial resolution Vertex Detector which enables the reconstruction of secondary vertices from open charm meson decays. In this presentation the first meson yields at the SPS energy regime will be shown. The analysis used the most central 20% of Xe+La collisions at 150A GeV/c from the data set collected in 2017. This allowed the estimation of the corrected yields (dN/dy) for via its decay channel at mid-rapidity in the center-of-mass system. The results will be compared and discussed in the context of several model calculations including statistical and dynamical approache
Testbeam Characterization of a SiGe BiCMOS Monolithic Silicon Pixel Detector with Internal Gain Layer
No full textA monolithic silicon pixel ASIC prototype, produced in 2024as part of the Horizon 2020 MONOLITH ERC Advanced project, wastested with a 120 GeV/c pion beam. The ASIC features a matrix ofhexagonal pixels with a 100 μm pitch, read by low-noise,high-speed front-end electronics built using 130 nm SiGe BiCMOStechnology. It includes the PicoAD sensor, which employs acontinuous, deep PN junction to generate avalanche gain. Data weretaken across power densities from 0.05 to 2.6 W/cm and sensorbias voltages from 90 to 180 V. At the highest bias voltage,corresponding to an electron gain of 50, and maximum power density,an efficiency of (99.99 ± 0.01)% was achieved. The timeresolution at this working point was (23.9 ± 0.2) ps beforetime-walk correction, improving to (12.1 ± 0.3) ps aftercorrection.A monolithic silicon pixel ASIC prototype, produced in 2024 as part of the Horizon 2020 MONOLITH ERC Advanced project, was tested with a 120 GeV/c pion beam. The ASIC features a matrix of hexagonal pixels with a 100 μ m pitch, read by low-noise, high-speed front-end electronics built using 130 nm SiGe BiCMOS technology. It includes the PicoAD sensor, which employs a continuous, deep PN junction to generate avalanche gain. Data were taken across power densities from 0.05 to 2.6 W/cm2 and sensor bias voltages from 90 to 180 V. At the highest bias voltage, corresponding to an electron gain of 50, and maximum power density, an efficiency of (99.99 ± 0.01)% was achieved. The time resolution at this working point was (24.3 \pm 0.2) ps before time-walk correction, improving to (12.1 \pm 0.3) ps after correction
Enhancing product management in the ATLAS Management Glance team
No full textCERN has a very dynamic environment and faces challenges such as information centralization, communication between the experiments’ working groups, and the continuity of workflows. The solution found in 2003 for those challenges was automation and, therefore, the Glance project, an essential management software tool for all four large LHC experiments. Its main purpose is to develop and maintain web-based automated solutions that are easy to learn and use and allow collaboration members to perform their tasks quickly. The ATLAS Management Glance team (AMGT) is a subset of the Glance team focused on addressing the software requests of the ATLAS Spokesperson and deputies. The team maintains 11 systems that allow the management of ATLAS members, appointments, analyses, speaker nomination, and selection, among other tasks. Historically, each Glance developer would be an expert in the requirements of one or more systems, but their product management was inefficient, lacking the mapping of the product vision, goals, business rules, stakeholders, and metrics. Also, the team's roadmap lacked predictability since it had no planned timeline. In December 2023, the AMGT adopted the Product Owner role concentrated in a single person as stated in the Scrum Guide. This contribution dives into the challenges faced by the Glance Team Product Owner in establishing a strategy for effective product management and roadmap planning and the key takeaways from that process
Discovery potential of LHCb Upgrade II
No full textA second major upgrade of the LHCb detector is necessary to allow full exploitation of the HL-LHC for flavour physics. The new detector will be installed during long shutdown 4 (LS4), and will operate at instantaneous luminosity up to . By upgrading all subsystems and adding new detection capability it will be possible to accumulate a sample corresponding to an integrated luminosity of at least of high energy collision data, giving unprecedented and unique scientific opportunities in flavour physics, in electroweak physics, in searches for new feebly interacting particles and in hadron spectroscopy. In this document, the potential of the LHCb Upgrade II detector to enable major discoveries through increased sensitivity to a range of as-yet unknown phenomena is summarised.A second major upgrade of the LHCb detector is necessary to allow full exploitation of the HL-LHC for flavour physics. The new detector will be installed during long shutdown 4 (LS4), and will operate at instantaneous luminosity up to . By upgrading all subsystems and adding new detection capability it will be possible to accumulate a sample corresponding to an integrated luminosity of at least of high energy collision data, giving unprecedented and unique scientific opportunities in flavour physics, in electroweak physics, in searches for new feebly interacting particles and in hadron spectroscopy. In this document, the potential of the LHCb Upgrade II detector to enable major discoveries through increased sensitivity to a range of as-yet unknown phenomena is summarised.A second major upgrade of the LHCb detector is necessary to allow full exploitation of the HL-LHC for flavour physics. The new detector will be installed during long shutdown 4 (LS4), and will operate at instantaneous luminosity up to . By upgrading all subsystems and adding new detection capability it will be possible to accumulate a sample corresponding to an integrated luminosity of at least of high energy collision data, giving unprecedented and unique scientific opportunities in flavour physics, in electroweak physics, in searches for new feebly interacting particles and in hadron spectroscopy. In this document, the potential of the LHCb Upgrade II detector to enable major discoveries through increased sensitivity to a range of as-yet unknown phenomena is summarised
