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1st FCC-ee TDAQ Workshop
No full textOverview of the many beam background sources, highlighting the simulation status of each, with a target audience of the detector concept community (to use for occupancy studies and similar
1st FCC-ee TDAQ Workshop
No full textOverview of digitisation status for different detector concept sub-detector
LHCb-Autoencoders for real-time event selection at the LHCb experiment
No full textThe second software trigger (HLT2) of the LHCb experiment employs a combination of cut-based and multivariate selections, with the latter achieving superior performance but requiring background samples for training. This work investigates an alternative, unsupervised approach based on an autoencoder trained exclusively on signal Monte Carlo (MC) samples of the decay . The autoencoder is trained using approximately 200k truth-matched events and evaluated using HLT1-filtered data to estimate trigger rates as a function of the reconstruction-error threshold. For the studied decay, the method provides both higher signal efficiency and lower rate compared to the current cut-based HLT2 line. The trained model is deployed in HLT2 through the ONNX framework, enabling real-time operation. The new selection has been active since the September MD, and its performance during data taking and its implications for offline analyses are currently under evaluation
ATLAS, beyond the Standard Model
No full textMany theories beyond the Standard Model (SM) have been proposed to address several of the SM shortcomings, such as explaining why the Higgs boson is so light, the origin of neutrino masses, or the observed pattern of masses and mixing angles in the quark and lepton sectors. Many of these beyond-the-SM extensions predict new particles or interactions directly accessible at the LHC. This talk will present some highlights on recent searches based on Run 2 and Run 3 data collected by the ATLAS collaboration
View of Science Gateway with snow in the background
No full textView of Science Gateway with snow in the backgroun
Hunting the dark-Higgs: A search for a dark-Higgs boson in the 4 final state at TeV with the ATLAS detector.
No full textThe Standard Model of particle physics, while remarkably successful in describing most phenomena related to the fundamental interactions and particles, notably lacks a mechanism to account for dark matter, prompting a wealth of beyond the Standard Model (BSM) theories that propose various candidates and interactions. One such theory is the dark Higgs boson model. This model introduces three additional states: the dark matter candidate; a dark Higgs boson responsible for giving mass to the dark matter candidate; and a heavy spin-1 mediator (). It is able to reproduce the observed relic density naturally. A search for a di-Higgs resonance will be presented, with each Higgs decaying to two b-jets, paired with significant missing transverse momentum (MET), in 140/fb of pp collision data recorded by the ATLAS experiment at =13 TeV. This signature provides the first sensitivity for the process where the radiates a dark Higgs, the decays to two dark matter particles, and the dark Higgs into two Higgs bosons, likely for a sufficient dark Higgs mass. A specialised neural network approach is used, decorrelated with the di-Higgs mass (a proxy for the dark Higgs mass), to enhance the sensitivity of our search, enabling the analysis to probe the previously unexplored parameter space of high- and dark-Higgs masses
Complex Parsing for In-Network Acceleration of High-Energy Physics Experiments
No full textThis paper describes a novel application and evaluation of programmable networking in High-Energy Physics (HEP): a complete parser for the custom packet format used by Fermilab’s DUNE experiment. Notably, this parser is implemented on a Tofino programmable network switch and evaluated on the FABRIC testbed by using network traffic generated by the ICEBERG DUNE prototype. The parsed network traffic consists of Jumbo Ethernet frames that contain digitizations of sensor readings from ICEBERG’s detector.This work is an early investigation into providing in-network processing support for HEP experiments. The paper describes DUNE’s custom packet format, the challenges encountered when implementing a parser for that format, and an exploration of the techniques that are needed to overcome those challenges. We identify performance bottlenecks and discuss directions for future research
Powering the Future: Next-Gen Power and Detector Control System for the HL-LHC Upgrade
No full textThe background radiation levels expected at the High-Luminosity LHC (HL-LHC) will substantially exceed those for which the ATLAS Muon Spectrometer was originally designed. To meet this challenge, the Monitored Drift Tube (MDT) chambers in the barrel inner small sectors will be replaced with new small-diameter MDT (sMDT) chambers. This upgrade also enables the installation of an additional triple-layer of Resistive Plate Chambers (RPCs), which will significantly enhance the performance of the Level-1 muon trigger system. In parallel with the R&D efforts for these new detectors, the development of a reliable and user-friendly Detector Control System (DCS) has been a key priority. The DCS for the (s)MDT power supply builds upon the proven design philosophy of the legacy systems, preserving their graphical interface and command structure. Its primary objective is to ensure coherent and safe detector operation by continuously monitoring critical parameters and system status. One of the main differences between the legacy and the Phase-2 Power System (PS) lies in the branch controller architecture: the A1676A module, together with its mainframe SY4527, has been consolidated into a single standalone unit, the R6060. To validate both the new detector technologies and the updated control architecture, a series of dedicated tests were conducted. In particular, the performance of the new power system was assessed using a slice of the RPC detectors currently installed in the ATLAS experiment. These tests demonstrated performance improvements of up to a factor of 40 over the A1676A system, depending on the operating conditions. Additionally, a full-scale test setup reproducing the complete power supply configuration for three MDT chambers has been installed. This setup serves multiple purposes: it acts as a validation platform, a reference system for all Muon sub-detectors in test environments, a support tool for pre-commissioning activities at Point 1 (P1), and a training facility for new DCS experts—thereby facilitating knowledge transfer and ensuring operational readiness for the HL-LHC era