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Measurement of the branching fraction of the decay and isospin asymmetry of decays
No full textThis paper describes a measurement of the branching fraction using data collected with the LHCb experiment in proton-proton collisions from 2016 to 2018. The dataset corresponds to an integrated luminosity of 5.4\. The branching fraction is determined relative to that of decays, yielding , where the first uncertainty is statistical, the second systematic, the third due to external inputs on branching fractions and the fourth due to the ratio of baryon and meson hadronisation fractions. In addition, the isospin asymmetry between the rates of and decays is measured to be where the first uncertainty is statistical and the second systematic.This paper describes a measurement of the branching fraction using data collected with the LHCb experiment in proton-proton collisions from 2016 to 2018. The dataset corresponds to an integrated luminosity of 5.4. The branching fraction is determined relative to that of decays, yielding , where the first uncertainty is statistical, the second systematic, the third due to external inputs on branching fractions and the fourth due to the ratio of baryon and meson hadronisation fractions. In addition, the isospin asymmetry between the rates of and decays is measured to be , where the first uncertainty is statistical and the second systematic
Search for resonances decaying to an anomalous jet and a Higgs boson in proton-proton collisions at 13 TeV
No full textThis paper presents a search for new physics through the process where a massive particle, X, decays into a Higgs boson and a second particle, Y. The Higgs boson subsequently decays into a bottom quark-antiquark pair, which is reconstructed as a single large-radius jet. The decay products of Y are also assumed to produce a single large-radius jet. The identification of the Y particle is enhanced by computing the anomaly score of its candidate jet using an autoencoder, which measures deviations from typical quark- or gluon-induced jets. This allows a simultaneous search for multiple Y decay scenarios within a single analysis. In the main benchmark process, Y is a scalar particle that decays into a W boson pair. Two other scalar Y decay processes are also considered as benchmarks: decays to a light quark-antiquark pair, and decays to a top quark-antiquark pair. A fourth benchmark process considers Y as a hadronically decaying top quark, arising from the decay of a vector-like quark into a top quark and a Higgs boson. Data recorded by the CMS experiment at a center-of-mass energy of 13 TeV in 2016-2018, corresponding to an integrated luminosity of 138 fb, are analyzed. No significant excess above the standard model background expectation is observed. The most stringent upper limits to date are placed on benchmark signal cross sections for various masses of X and Y particles.This paper presents a search for new physics through the process where a new massive particle, X, decays into a Higgs boson and a second particle, Y. The Higgs boson subsequently decays into a bottom quark-antiquark pair, reconstructed as a single large-radius jet. The decay products of Y are also assumed to produce a single large-radius jet. The identification of the Y particle is enhanced by computing the anomaly score of its candidate jet using an autoencoder, which measures deviations from typical QCD multijet jets. This allows a simultaneous search for multiple Y decay scenarios within a single analysis. In the main benchmark process, Y is a scalar particle that decays into WW. Two other benchmark processes are also considered, where Y is a scalar particle decaying into a light quark-antiquark pair, or into a top quark-antiquark pair. The last benchmark considers Y as a hadronically decaying top quark, arising from the decay of a vector-like quark into a top quark and a Higgs boson. Data recorded by the CMS experiment at a center-of-mass energy of 13 TeV in 20162018, and corresponding to an integrated luminosity of 138 fb, are analyzed. No significant excess is observed, and upper limits on the benchmark signal cross section for various masses of X and Y, at 95% confidence level, are placed
Open Science Fair 2025
No full textWith the increasing popularity of preprints, there are ongoing discussions among the research community about the need to apply peer review to help readers navigate new findings. eLife adopted such an approach in 2023, when we launched our model for publishing. The outputs are Reviewed Preprints, which include the original preprint, public reviews and an eLife Assessment that conveys the significance of the findings and strength of evidence, allowing readers to judge the research based on its own merits rather than where it is published.
Due to our efforts to challenge the status quo in publishing, our indexing status in Web of Science changed last year, meaning eLife no longer receives an Impact Factor. This was followed by concerns that eLife papers would no longer count toward funding or career progression opportunities. We therefore spoke to funders and institutions globally to better understand their position, and reported that 95% of respondents still consider eLife papers when evaluating research contributions. Our conversations highlighted that there is less consideration for the Impact Factor than perceived by the research community, and signalled broad support for more open science practices – showing that it’s time to move away from journal metrics in favour of more transparent and meaningful methods of assessment.
In this session, we will talk more about eLife Assessments, our conversations with the community and why it’s time to embrace innovative approaches to research assessment that better serve science and scientists. We also invite further discussion and participation from the audience
Input to the ESPPU 2026 update: Searching for millicharged particles with the FORMOSA experiment at the CERN LHC
No full textIn this contribution, we evaluate the sensitivity for particles with charges much smaller than the electron charge with a dedicated scintillator-based detector in the far forward region at the CERN LHC, FORMOSA. This contribution will outline the scientific case for this detector, its design and potential locations, and the sensitivity that can be achieved. The ongoing efforts to prove the feasibility of the detector with the FORMOSA demonstrator will be discussed. Finally, possible upgrades to the detector through the use of high-performance scintillator will be discussed
Performance Highlights of the ATLAS Detector
No full textThe ATLAS experiment at the Large Hadron Collider (LHC) continues to deliver high-precision measurements and new physics insights through its extensive dataset collected during Run 2 and the ongoing Run 3. The performance of key detector subsystems, including tracking, calorimetry, and muon detection, plays a crucial role in ensuring the accuracy of physics analyses. This review presents recent highlights from ATLAS performance studies, covering improvements in object reconstruction and calibration techniques. Emphasis is placed on efficiency, resolution, and systematic uncertainties affecting key physics observables, as well as the ongoing efforts to optimize detector performance for future data-taking periods, such as for the HL-LHC
EFT results in the top quark sector in ATLAS
No full textSLIDES of recent ATLAS results including EFT interpretations for the Top2025 conferenc
Strategies and performances of the CMS trigger in Run 3
No full textThe Compact Muon Solenoid experiment at the Large Hadron Collider employs a two-level trigger system to select physics events of interest from high-rate collisions. The third operational period of the accelerator, Run 3, which began in 2022, presents new challenges with unprecedented levels of simultaneous collisions in a single bunch crossing (pileup). To meet the demands of an ambitious physics program, CMS has deployed a significantly upgraded trigger strategy. At the first stage, the hardware-based Level-1 Trigger, new algorithms have been implemented to enhance sensitivity to rare and unconventional signatures, such as those from long-lived particles, and to perform model-agnostic anomaly detection in real time. At the second stage, the software-based High-Level Trigger, substantial performance gains have been achieved through the integration of a heterogeneous computing architecture that offloads a significant part of the event reconstruction to Graphics Processing Units. This has enabled the use of faster, more efficient reconstruction algorithms, including a new single-iteration tracking approach and the deployment of advanced machine learning models like ParticleNet for jet flavor identification. Furthermore, CMS has greatly expanded its data-taking capacity through enhanced data parking and scouting streams. This paper provides a comprehensive overview of these new trigger strategies and reports on their excellent performance during the first years of Run 3
