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EOS 2024 Workshop
In close collaboration with the IT procurement team we have conducted R&D with EOS and SMR disks. The findings, current status and outlook on integration of SMR disks will be covered in this presentation
Enabling Real-Time Impedance Measurements of Operational Superconducting Circuits of Accelerator Magnets
Impedance measurements of superconducting circuits routinely serve as means to anticipate their dynamic response and validate their electrical integrity. Usual procedures involve performing tests on non-powered systems during commissioning and maintenance periods. However, impedance measurements might have a strong potential in diagnostics of powered superconducting circuits as well. In particular, they should allow for on-line fault monitoring, enhanced quench detection, and deeper insight into the electrical properties of the circuits such as impedance variations or non-linear effects in the operational conditions. This paper outlines the design of an experimental platform enabling such an evaluation. In essence, this system is capable of injecting electrical stimuli into a magnet circuit and capturing the response. The acquired data are processed in order to extract circuit characteristics, in particular the impedance and its temporal evolution. In addition to discussing key design considerations related to measurement performance such as bandwidth, resolution, and sensitivity, the paper explores how to maintain transparent operation with respect to peripheral components such as the power converters and quench protection systems. Finally, the paper presents the validation campaign of the designed solution. The validation consists of two stages, including non-powered and powered superconducting circuits. The former case compares performance of the system to a state-of-the-art industrial impedance analyser, while the latter focuses on the impact the system has on peripheral components. Presented conclusions provide guidelines for front-end instrumentation design and data processing in order to enhance performance evaluation of superconducting circuits in their entire operational spectrum
Half-life determination of At and Ra with high-purity radioactive ion beams
At CERN-ISOLDE, high-purity radioactive ion beams of Fr and RaF were investigated with -decay spectroscopy at the CRIS and ASET experiments in the course of three different experimental campaigns. The half-life of At, -decay daughter of Fr, is measured to be 36.3(3)[9]μs, and that of Ra was determined to be 26.2(1)[6]s, both of which are well in line with the trends in this region of the nuclear landscape but at odds with some of the reported literature
CERN Tape Archive Workshop : CTA 2024
The configuration of the CTA tape daemon was inherited from CASTOR, which relied on a manual process to create and store the configuration for each tape drive. As the scale of CERN's tape operations have grown to hundreds of drives, this approach has not scaled well. The CTA team have therefore developed a new semi-automated process to determine the configuration of each drive. The configuration has been simplified and refactored, making it easier to operate multiple tape drives per tape server. In this two-part presentation we will describe: the procedure to automatically obtain the drive information from the library; and the new tape daemon configuration file structure and how to configure multiple drives per tape server
The latest highlighted measurements of the Standard Model with the ATLAS Experiment
We selects the recent high precision measurements and exciting observations with covering the topics of vector boson, multi-jets and top productions extensively, together with the further interpretations as for the determinations of fundamental parameters of the standard model, confrontations with the state-of-art predictions and constrains of new physics via the model independent way
Characterization of Hysteretic Behavior of a FeCo Magnet for the Design of a Novel Ion Gantry
In the framework of the euroSIG project and within an international collaboration between CNAO, CERN, INFN, and MedAustron, the design of a novel gantry for hadron therapy based on superconducting magnets and a downstream scanning system has been undertaken. The choice of placing the scanning system downstream of the last superconducting dipole plays a crucial role in the overall layout of the gantry, having a direct impact on its radius, weight, and cost. The proposed design for the scanning system considers two separate normal-conducting scanning magnets with a central field in the order of 1 T, three times higher than the current state-of-the-art scanning magnets for hadron therapy. Such a magnetic field value for a fast-pulsed magnet poses interesting questions regarding non-linearities due to the yoke saturation, hysteretic effects, and eddy currents. In this context, it is important to develop reliable models to study the behavior of the magnet at various levels of current and magnetic field. For this reason, we implemented two and three-dimensional simulations of a short dipole with FeCo yoke and we validated them against experimental measurements. In this paper, we focus on the modelization of the hysteretic behavior of this magnet, providing insight into the feasibility of proposed scanning magnets
CERN Tape Archive Workshop : CTA 2024
At the 2nd CTA Workshop (2023), we announced a repository of Free and Open Source operator tools for CTA, including the Repack automation system (ATRESYS) tool. Since then, the repository has seen a number of new tool additions, as well as changes to the underlying libraries.
In this talk, we will introduce these new features, including tools for: automating the supply of tapes to tape pools; automated validation of data on tape; EOSCTA disk file metadata operations; and higher-level CTA operator tasks. Together, these make up the backbone of the tape operations ecosystem at CERN. We present these contributions in the hope that they will be as useful to the CTA community at large
Search for the lepton flavour violating decays and with LHCb Run 2 data
A large variety of new physics models suggest that the rates for lepton flavour violating -hadron decays may be much higher than predicted in the Standard Model, which leads to a high interest in the search for such decays. This thesis presents the search for the lepton-flavour violating decays and with the data sample collected by the LHCb experiment between 2016 and 2018, which corresponds to an integrated luminosity of 5.4 fb of proton-proton collisions. The analysis is performed while blinding the signal mass region, to avoid any bias introduced by the experimenter. The and branching fractions are measured with respect to the high statistics decay, with a fit to the invariant mass distribution in six independent data samples characterized by different background levels and signal mass resolutions due to electron bremsstrahlung. A dedicated selection is used to reduce background from random combinations and specific physics decays with a multivariate analysis and particle identification requirements, respectively. Efficiencies are determined from simulation, corrected for mismodeling effects with data-driven methods, and validated by measuring . The main physics backgrounds are identified to arise from decays to the , , and final states, and taken into account in the mass fit; the yields of the two components peaking in the signal mass window, (12.2 events) and (7.7 events), are estimated from simulation and validated with two independent data-driven methods. Pseudo-experiments are performed to test the fit stability, study potential biases, and estimate the sensitivity of the analysis. In absence of signals and without any systematic uncertainty considered, the average expected upper limits at 95%(90%) confidence level are estimated to be , and or assuming the decay amplitude is completely dominated by the light (short-lived) or heavy (long-lived) mass eigenstate of the system, respectively. This is an improvement in sensitivity by a factor 1.6 for and 2.8 for (when dominated by the heavy eigenstate), with respect to the previous best expected limits published by LHCb with the 2011 and 2012 data. In addition, this thesis presents the quality assurance process of silicon photomultiplier detectors used for the Scintillating Fibre (SciFi) tracker of the recent LHCb detector upgrade