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Artwork illustrating current and projected CMS integrated luminosity, with selected results and prospects
No full textAn artwork (infographic) depicting integrated luminosity collected by the CMS detector until now, and projected to 2041. Pointers to selected physics results highlights, and possibilities for the future, are also depicted
Exotics searches at ATLAS (prompt)
No full textDespite the success of the Standard Model in predicting most of the phenomena observed in particle physics experiment, some observational evidences and theoretical inconsistencies motivate the search for exotic phenomena. Four exotic searches based on the LHC Run 2 data collected by the ATLAS detector are highlighted in this contribution, mainly concerning the Dark Matter and the hierarchy problems
D1 cold mass for HL-LHC in finalisation zone
No full textThe first of the six D1 separation and recombination dipole (MBXF) series from KEK, Japan was delivered to CERN. After cryostating, the D1 will be cold tested in its final configuration in SM18
Hadron spectroscopy and hadron-hardon interactions
No full textThese proceedings present a selection of results on behalf of all the experiments at LHC. This contribution covers a selection of results appeared after the 2024 winter conferences and before ICHEP2024. Highlights include the observation of new charmonium(-like) states in decays and exotic resonances produced in central exclusive production collisions. Additionally, the Elliptic anisotropy measurement of the f0(980) hadron in proton-lead collisions at CMS is described, along with a similar analysis by the ALICE experiment on the observation of abnormal suppression of f0(980) production in p-Pb collisions
ALICE Forward Calorimeter upgrade (FoCal): Physics program and performance
No full textA new high-precision forward calorimeter (FoCal) is about to be installed in the ALICE experiment at the LHC during Long Shutdown 3 for data-taking in the LHC Run 4 that is currently scheduled for the period 2030-2033. FoCal consists of a Si+W sampling electromagnetic calorimeter with longitudinal and transverse segmentations (FoCal-E) and a conventional Cu+scintillating-fiber hadronic calorimeter (FoCal-H). FoCal has a front face of approximately 90 90 cm and isplaced at z 7 m from the nominal interaction point. It covers the pseudo-rapidity range of 3.2 5.8. FoCal has unique capabilities to measure the direct photon production at the forward rapidity that probes the gluon distribution in protons and nuclei at small-. Furthermore, FoCal will enable to carry out inclusive and correlation measurements of photons, neutral mesons and jets in hadronic pp and p-Pb collisions aswell as J/ production in the ultra-peripheral p-Pb and Pb-Pb collisions. We developed a full-length detector prototype and studied its performance such as a response to minimum ionizing particles and a longitudinal shower profile of electromagneticshowers at the CERN PS and SPS complexes in 2022-2023. We tested the silicon pad sensors for FoCal-E at the RIKEN Accelerator-driven compact neutron systems (RANS) facility in Japan in 2022-2024 and they have the radiation tolerance to withstand the full operation at the LHC Run 4.Mass production of FoCal will begin soon
Search for jet quenching in small systems
No full textHigh multiplicity final states of small collision systems, such as proton-proton or proton-nucleus, exhibit some signatures which resemble features associated with QGP formation in heavy-ion collisions, e.g., collective phenomena or enhancement in produced strangeness. At the same time, there is no experimental evidence for QGP-induced jet quenching to date. Thus, quantification or setting limits on the magnitude of jet quenching in small systems is essential for understanding the conditions needed for QGP formation. These proceedings discuss several recent measurements that searched for jet quenching effects in small collision systems.High multiplicity final states of small collision systems, such as proton-proton or proton-nucleus, exhibit some signatures which resemble features associated with quark-gluon plasma (QGP) formation in heavy-ion collisions, e.g., collective phenomena or enhancement in produced strangeness. At the same time, there is no experimental evidence for QGP-induced jet quenching to date. Thus, quantification or setting limits on the magnitude of jet quenching in small systems is essential for understanding the conditions needed for QGP formation. These proceedings discuss several recent measurements that searched for jet quenching effects in small collision systems
Combination of searches for resonant Higgs boson pair production using collisions at = 13 TeV with the ATLAS detector
No full textCombination of searches for the resonant production of Higgs boson pairs is performed in the , , and decay channels using up to 139~fb of proton-proton collision data at a center-of-mass energy of 13 TeV recorded by the ATLAS detector at the LHC. No significant excess over the expected background was observed, and upper limits were set at the 95\% confidence level on the production cross section of Higgs boson pairs from the decay of a narrow scalar resonance with masses ranging from 251 GeV to 5 TeV. The observed (expected) upper limits range from 0.96 to 600 fb (1.2 to 390 fb). These results are interpreted in the context of the Type-I Two-Higgs-Doublet Model (2HDM) and the Minimal Supersymmetric Standard Model (MSSM), tightening constraints on parameter spaces not previously excluded by other searches
Generative models and seq2seq techniques for the flash-simulation of the LHCb experiment
No full textSimulating detector and reconstruction effects on physics quantities is crucial for data analysis, but it is coming unsustainably costly for the upcoming HEP experiments. The most radical approach to speed-up detector simulation is Flash Simulation, as proposed by the LHCb collaboration in Lamarr, a software package implementing a novel simulation paradigm relying on Deep Generative Models and Seq2seq attention-driven techniques to deliver simulated samples. Thanks to its modular layout, Lamarr provides analysis-level quantities by applying a pipeline of machine learning-based modules that properly transforms the information resulting from physics generators. Good agreement is observed by comparing key reconstructed quantities obtained with Lamarr against those from the existing detailed Geant4-based simulation. Lamarr has been designated with dual capabilities: it can function as a stand-alone simulation framework, while also being seamlessly integrated into the LHCb simulation software