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Open Science Fair 2025
No full textThis panel confronts the critical tension between openness and security in today’s Open Science landscape. As AI revolutionizes research, it also introduces significant risks like disinformation and trust erosion. Compounding this, geopolitical strains force a reassessment of knowledge sharing, further undermining scientific trust. We are caught in an "information paradox": unparalleled access to knowledge alongside a public debate degraded by misinformation, shaking faith in science and democratic institutions. At the heart of this lies a vulnerable "public knowledge infrastructure" spanning research, education, and media. While openness is vital for progress, it demands careful governance.
This session will explore proactive strategies and collaborative solutions. We will examine how infrastructures like OPERAS, OpenAIRE, and EOSC champion vetted, multilingual open research through transparency and initiatives such as the Information Quality Protocol (IQP). The discussion will focus on uniting diverse "knowledge workers," fostering citizen engagement, and rebuilding our knowledge infrastructure. Key themes include robust governance, quality standards, and collective action to safeguard reliable open knowledge, counter disinformation, and restore public trust. Ultimately, the panel will address how Open Science can securely foster an informed, resilient, and democratic society
The ATLAS High-Granularity Timing Detector for the HL-LHC
No full textThe increase of the particle flux (pile-up) at the HL-LHC with instantaneous luminosities up to L ≃ 7.5 × 10 cms will have a severe impact on the ATLAS detector reconstruction and trigger performance. The end-cap and forward region where the liquid Argon calorimeter has coarser granularity and the inner tracker has poorer momentum resolution will be particularly affected. A High Granularity Timing Detector (HGTD) will be installed in front of the LAr endcap calorimeters for pile-up mitigation and luminosity measurement. The HGTD is a novel detector introduced to augment the new all-silicon Inner Tracker in the pseudo-rapidity range from 2.4 to 4.0, adding the capability to measure charged-particle trajectories in time as well as space. Two silicon-sensor double-sided layers will provide precision timing information for minimum-ionising particles with a resolution as good as 30 ps per track in order to assign each particle to the correct vertex. Readout cells have a size of 1.3 mm × 1.3 mm, leading to a highly granular detector with ~3.7 million channels. Low Gain Avalanche Detectors (LGAD) technology has been chosen as it provides enough gain to reach the large signal over noise ratio needed. The requirements and overall specifications of the HGTD will be presented as well as the technical design and the project status. The R&D effort carried out to study the sensors, the readout ASIC, and the other components, supported by laboratory and test beam results, will also be presented
A method for measuring energy gain with variable plasma length at AWAKE
No full textThe AWAKE experiment investigates the acceleration of externally injected electrons into the wakefields driven by a self-modulated proton bunch. In Run 1, AWAKE successfully demonstrated proton bunch self-modulation and accelerated electrons from 19 MeV to 2 GeV. For Run 2b, upgrades to the rubidium vapour source enabled the introduction of a plasma density step and adjustments to the plasma length. This facilitated studies on how the density step sustains the longitudinal wakefield amplitude by measuring the electron energy gain as a function of the plasma length. This paper presents the analysis techniques for such energy measurements and the technical considerations for interpreting results under the varying plasma conditions
Measurement of the top-quark Yukawa coupling from production in the lepton+jets final state using collisions at TeV with the ATLAS detector
No full textThe top-quark Yukawa coupling is extracted from the distribution of the top-quark pair () invariant mass in proton-proton collisions using 140 of data at TeV collected in 2015-2018 by the ATLAS experiment at the Large Hadron Collider. In the region near the production threshold, the invariant mass spectrum is sensitive to electroweak virtual corrections, including contributions from Higgs boson exchange, thereby providing sensitivity to the top-quark Yukawa coupling. This is the first measurement in ATLAS that aims to obtain this coupling exploiting this approach. The system is reconstructed in the single-lepton final state, requiring exactly one isolated electron or muon and at least four jets with at least two identified as originating from -quarks. The measured Yukawa coupling is found to be in good agreement with the Standard Model prediction. An upper limit on the top-quark Yukawa coupling strength of relative to the Standard Model prediction is observed at 95% confidence level, consistent with the expected sensitivity.The top-quark Yukawa coupling is extracted from the distribution of the top-quark pair () invariant mass in proton-proton collisions using 140 fb of data at TeV collected in 2015-2018 by the ATLAS experiment at the Large Hadron Collider. In the region near the production threshold, the invariant mass spectrum is sensitive to electroweak virtual corrections, including contributions from Higgs boson exchange, thereby providing sensitivity to the top-quark Yukawa coupling. This is the first measurement in ATLAS that aims to obtain this coupling exploiting this approach. The system is reconstructed in the single-lepton final state, requiring exactly one isolated electron or muon and at least four jets with at least two identified as originating from -quarks. The measured Yukawa coupling is found to be in good agreement with the Standard Model prediction. An upper limit on the top-quark Yukawa coupling strength of relative to the Standard Model prediction is observed at 95% confidence level, consistent with the expected sensitivity
Electron beam scattering in Rubidium vapour at AWAKE
No full textThe Advanced Wakefield Experiment (AWAKE) at CERN uses bunches from the CERN SPS to develop proton-driven plasma wakefield acceleration. AWAKE Run 2c (starting in 2029) plans for external on-axis injection of a 150MeV electron witness bunch with the goal to demonstrate emittance control of multi-GeV accelerated electron beams. Prior to injection, the electron witness bunch may have to traverse rubidium vapour. Since the beam must have the correct beam size and emittance at injection, it is important to quantify the scattering effect. For this, first-principle estimates and simulations are compared with measurements of a 20MeV electron beam scattering in 5.5m of rubidium vapour, showing good agreement. Building on this agreement, simulations using the estimated AWAKE Run 2c parameters are performed. These predict that scattering will not increase the electron beam size or emittance
Impedance Reduction of the Beam Wire Scanners for the CERN LHC
No full textThe beam wire scanners are instruments for precise transverse beam profile measurements by detecting the secondary particles generated from the interaction of the beam with a moving carbon wire. Following a completely new design of this device for the Large Hadron Collider (LHC), a detailed impedance calculation has been performed already in the design phase. This contribution presents the beam coupling impedance optimization and reduction strategy of the beam wire scanners for the High-Luminosity (HL) upgrade of the LHC. Prior to the construction of the prototype, extensive three-dimensional electromagnetic simulations of the proposed mechanical designs were performed to detect potential resonances and their sources. The mechanical model was improved to minimize the beam coupling impedance by geometrical modifications and coatings. We also present the beam-induced RF power loss calculation of the instrument
2nd DRD3 school on TCT - Transient Current Technique
No full textParticipants of the 2nd DRD3 school on TC
Search for Heavy Stable Charged Particles with L1 Scouting Data at the CMS experiment
No full textHeavy long-lived charged particles crossing the CMS muon chambers in several bunch crossings are searched for using 3.7 fb−1 of data collected in 2024 at a center-of-mass energy of 13.6 TeV. The search relies on a new data set, so called Level-1 Scouting, collected without any trigger selection, allowing for correlations between bunch crossings to be analyzed. This analysis complements existing searches for heavy long-lived charged particles by extending the sensitivity to lower beta values.
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Design and Performance of the FBCM23 ASIC for the CMS Luminosity Measurement
No full textWe present the design and evaluation of the FBCM23 ASIC designed for the Fast Beam Condition Monitoring (FBCM) system intended for the luminosity measurements in the upgraded CMS experiment at CERN. The ASIC is implemented in a CMOS 65 nm technology and consists of six front-end channels with a binary architecture optimized to work with
1.7×1.7
mm2 area and 290 or
150μ
m thick silicon sensors. The presented ASIC will replace the existing system to comply with new, challenging specifications concerning the time resolution (1 ns rms) and noise, the latter related to the expected radiation damages of the sensors located at a radius close to 14.5 cm. The expected total ionizing dose (TID) and the fluence at the end of the experiment lifetime are 200 Mrad and
2.5×
10
15
n/
cm
2
, 1 MeV equivalent, respectively. We present the design and a complete characterization of the ASIC, including TID irradiation, single-event upset (SEU) tests, thermal drifts, and performance of the ASIC connected to the sensor