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The Universe for All: Hands-On Modern Physics for STEM Educators
No full textThe STEM education initiative “The Universe for All” is an international professional development program aiming to enhance science education through simple experiments and activities in modern physics and technology. In collaboration with leading institutions such as the Perimeter Institute for Theoretical Physics in Canada, the European Gravitational Observatory in Italy, a team of CERN researchers in Switzerland, and the Eugenides Foundation, as well as academic institutions in Greece, the program was piloted in Greece with science educators working in public primary and secondary schools. Quantitative and qualitative methods were employed to assess the program's effectiveness, focusing on the participant's needs and the impact on classroom teaching. Findings showed that hands-on teaching methods and direct interaction with researchers increased the educators' confidence and ability to engage students in STEM subjects. The collaboration fostered a shared learning environment. Suggestions were made for continuous scientific support and simplified educational tools. Overall, the educational program in question has the potential to enhance STEM education. The program's results indicate a strong need for continuous professional development in the modern sciences
Novel method to assess the electromagnetic radiation damage using HGCAL silicon sensors
No full textStudies of the silicon dioxide (SiO) passivation layer in n-on-p silicon sensors, which will be used in the CMS High Granularity Calorimeter (HGCAL), are important for improving their performance notonly at the High-Luminosity LHC, but also at future high-energy physics experiments.This work explores a novel method for estimating the effect of surface radiation damage on inter-pad isolation in HGCAL sensors by measuring the threshold voltage for inter-electrode isolation V. Test diodes with different SiO variants are irradiated with X-rays, and their characteristics are measured at a controlledtemperature of -20°C. The results are then compared with previous measurements with MOS andstrip-like sensors. Three measurement techniques — CV, IV, and interstrip like resistance measurements — are employed to extract V. Among these, the CV-based extraction method is found to be the most robust. The results show an unexpected dependence of V on the ionising dose, which has not been observed before. Possible explanations for the observed behaviour are also discussed
Few is different: deciphering many-body dynamics in mesoscopic quantum gases
No full textEmergent macroscopic descriptions of matter, such as hydrodynamics, are central to our description of complex physical systems across a wide spectrum of energy scales. The conventional understanding of these many-body phenomena has recently been shaken by a number of experimental findings. Collective behavior of matter has been observed in systems, such as high-energy hadron-hadron collisions, or ultra-cold gases with only few strongly interacting fermions. In such systems, the separation of scales between macroscopic and microscopic dynamics (at the heart of any effective theory) is inapplicable. To address the conceptual challenges that arise from these observations and explore the universality of emergent descriptions of matter, the EMMI Rapid Reaction Task Force was assembled. This document summarizes the RRTF discussions on recent theoretical and experimental advances in this rapidly developing field. Leveraging technological breakthroughs in the control of quantum systems, we can now quantitatively explore what it means for a system to exhibit behavior beyond the sum of its individual parts. In particular, the report highlights how the (in)applicability of hydrodynamics and other effective theories can be probed across three principal frontiers: the size frontier, the equilibrium frontier, and the interaction frontier
ATLAS New Small Wheel performance studies with LHC Run 3 data
No full textThe most important ATLAS upgrade for LHC run-3 has been in the Muon Spectrometer, where the replacement of the two forward inner stations with the New Small Wheels (NSW) introduced two novel detector technologies: the small-strip Thin Gap Chambers (sTGC) and the resistive strips Micromegas (MM). The integration of the two NSW in the ATLAS endcaps marks the culmination of an extensive construction, testing, and installation program. The NSW actively contributes to the muon spectrometer trigger and tracking, during the concurrent finalization of the commissioning phase of this innovative system and the optimization of its performances. This presentation will offer a detailed report on the studies on the NSW system, based on the LHC run-3 dataset collected from 2022 to 2024. The report will cover the performance of the two novel detector technologies, as well as the muon trigger and reconstruction performance in the ATLAS endcaps
High-Granularity Timing Detector for ATLAS experiment at HL-LHC
No full textHGTD talk in Lepton Photon 202
The ATLAS High-Granularity Timing Detector for the HL-LHC: project status and results
No full textThe increase of the particle flux (pile-up) at the HL-LHC with instantaneous luminosities up to L ≃ 7.5 × cm2 s-1 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
Operational Experience & Performance With the ATLAS Pixel Detector at the Large Hadron Collider at CERN
No full textThe tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector, with a sensitive area of ~1.9 m2 and 92 million pixels. Its original part, consisting in 3 layers of planar pixel sensor is continuously operating since the start of LHC collisions in 2008, while Its innermost layer, the Insertable B Layer (IBL) at about 3 cm from the beam line, was installed in 2015 before the start of LHC Run2 and consists of both planar and 3D pixel sensors, with FE-I4 readout frontends at 130nm CMOS technology. As the closest detector component to the interaction point, this detector is subjected to a significant amount of radiation over its lifetime. At present, before the start of 2025 Run3 LHC collisions, ATLAS Pixel Detector on innermost layers is operating after integrating fluence of O(10**15) 1 MeV n_eq cm-2. In this talk the key status and performance metrics of the ATLAS Pixel Detector are summarised, putting focus on performance and operating conditions at a over performing LHC, with special emphasis to radiation damage and mitigation techniques adopted, with prediction of their evolution until the end of LHC Run3 in 2026. These results provide useful indications for the optimisation of the operating conditions for the new generation of pixel trackers under construction for HI-LHC upgrades
tt +heavy flavor measurements from ATLAS
No full textProceedings on ttbar+heavy flavor measurements from ATLA
Probing fundamental symmetries with heavy flavor physics at CMS
No full textThis document presents recent results in heavy flavor physics, such as studies of lepton flavor universality in semi-leptonic decays, rare decays of mesons and spectroscopy of all-charm tetraquarks. All measurements are performed using proton-proton collision data at a center of mass energy of 13 TeV collected by the CMS detector at the LHC experiment
