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First fully exclusive reconstruction of radiative decays of the , , and mesons and measurement of their masses in proton-proton collisions at
No full textUsing a data sample corresponding to an integrated luminosity of of proton-proton collisions collected by the CMS experiment at in 2016--2018, the first full reconstruction of the three vector B meson states, , , and , is performed. The mass differences between the excited mesons and their corresponding ground states are measured to be , , and , where the first uncertainty is statistical and the second is systematic. These results are consistent with, and an order of magnitude more precise than, the current world average values
Measurement of the -boson mass
No full textThe first dedicated -boson mass measurement at the LHC with decays is reported. The dataset uses proton-proton collisions at a centre-of-mass energy of TeV, recorded in 2016 by the LHCb experiment, and corresponds to an integrated luminosity of fb. A template fit to the mass distribution yields the following result for the -boson mass, \begin{equation*} m_{Z} = 91184.2 \pm 8.5 \pm 3.8 \rm{MeV}, \end{equation*} where the first uncertainty is statistical and the second systematic. This result is consistent with previous measurements and predictions from global electroweak fits.The first dedicated Z-boson mass measurement at the LHC with Z→μ+μ- decays is reported. The dataset uses proton-proton collisions at a center-of-mass energy of 13 TeV, recorded in 2016 by the LHCb experiment, and corresponds to an integrated luminosity of 1.7 fb-1. A template fit to the μ+μ- mass distribution yields the following result for the Z-boson mass: mZ=91,185.7±8.3±3.9 MeV, where the first uncertainty is statistical and the second systematic. This result is consistent with previous measurements and predictions from global electroweak fits.The first dedicated -boson mass measurement at the LHC with decays is reported. The dataset uses proton-proton collisions at a centre-of-mass energy of TeV, recorded in 2016 by the LHCb experiment, and corresponds to an integrated luminosity of fb. A template fit to the mass distribution yields the following result for the -boson mass, \begin{equation*} m_{Z} = 91185.7 \pm 8.3 \pm 3.9 \rm{MeV}, \end{equation*} where the first uncertainty is statistical and the second systematic. This result is consistent with previous measurements and predictions from global electroweak fits
2nd FPGA Developers' Forum (FDF) meeting
No full textTime-to-digital converters (TDCs) are essential for precise time measurements in several domains. FPGA-based TDCs are a flexible, low-cost, highly customizable alternative. We have implemented an FPGA-based TDC based on a tapped delay line architecture, targeting the latest device families of AMD, to measure single particle transit times in a silicon sensor with a <30ps resolution at Particle Therapy clinical rate (average rate of 1e7-1e9 pps). This is highly needed for new in-vivo online treatment verification techniques, e.g. Prompt Gamma Timing. The TDC design relies on carry-logic blocks to introduce a small delay, and latch-based observation points placed at regular intervals along the chain to sample the signal at discrete time steps. Manufacturing process variations are addressed by acting directly on placement and routing. A synchronous counter is enabled to extend the measurement range. Experimental validation confirmed an average of 5.8 ps with an uncertainty of 30 ps
RPP Model Trends Across Technology Nodes for the MC Simulation of SEUs in Commercial Bulk Planar CMOS SRAMs Under Proton Irradiation
No full textThe ubiquitous use of electronic devices in high-radiation environments requires robust methods for assessing and improving their resilience against single-event effects (SEEs) and, especially, single-event upsets (SEUs). In this study, SEU production induced by protons below 500 MeV in three commercial bulk planar static random access memories (SRAMs) manufactured on different standard CMOS technology nodes (from 250 to 40 nm) is investigated employing the Monte Carlo (MC) particle-transport code FLUKA. A rectangular parallelepiped (RPP) model is adopted to describe the device geometry, relying on the sensitive volume (SV) and the critical charge as effective parameters. Optimal values of these two parameters that maximize the agreement between simulated and experimental SEU production cross sections are found for the three considered devices. Parameter trends in the RPP model across technology nodes are identified, thus providing practical guidelines when modeling components manufactured on other technology nodes
2nd FPGA Developers' Forum (FDF) meeting
No full textWith the increasing adoption of SoC-based systems in CERN Accelerator and Technology sector (ATS), new initiatives have been put in place to ensure that systems of similar form share as many components (hardware, gateware and software) as possible. These initiatives are grouped by the ATS SoC Framework Project, now under development. The first part of this talk gives an overview of some of the common challenges users face when using a SoC in the accelerator complex and it describes the tools the framework will provide to speed up and standardise the development of SoC-based applications.
The second part of the talk focuses on one of these initiatives, the DI/OT framework new standardized build system, which has been developed to generate boot images for these platforms. This build system is modular, expandable and designed to streamline the HDL synthesis and compilation of Xilinx SoC-based projects, with strong emphasis on re-usability and standardization. It is also CI-friendly, aligning with CERN IT's new CI4FPGA developments for CI runners and Docker images
ATLAS electron and photon energy calibration with Run 3 data
No full textposter at Higgs Pair 2025 on ATLAS electron and photon energy calibration with Run 3 dat
Non-resonant HH measurements in ATLAS and CMS
No full textSummary of the di-Higgs measurements in ATLAS and CMS
Search for displaced top quark in the tracker of the CMS experiment at the LHC
No full textA search for a massive long-lived particle decaying to a top quark in proton-proton collisions at = 13 TeV and 13.6 TeV is presented in this paper. Long-lived particles are predicted in several extensions of the Standard Model. In the R-parity violated Minimal SuperSymmetric Model considered, the lightest SuperSymmetric particle is long-lived and decays into a top quark and a virtual stop quark which couples to a down and strange quark pair. A multivariate analysis is used to distinguish signal displaced tracks from Standard Model prompt tracks for the reconstruction of displaced vertices
