Search for Higgs boson production in association with a high-energy photon via vector-boson fusion with decay into bottom quark pairs at = 13 TeV with the …

Wellcome Open Research

The term ‘executive functions’ (EFs) refers to a set of skills that support flexible control over thought and action. Classic EFs (working memory, inhibitory control, and cognitive flexibility) do not show measurable stable function until after the third year of life and continue to develop into early adulthood. However, even at the earliest ages, these EFs are shown to have value for predicting school readiness and academic achievement. They continue to have predictive value for success, mental health, and general well-being across the lifespan including in ageing populations. As such, understanding the developing brain and cognitive developmental dynamics that set the stage for the development of EFs, in the first three years of life, is crucial for developing programming that supports healthy EFs development. The goal of this manuscript is to describe the goals, hypotheses, participant populations, and methodology of the Khula Study. Khula is a multi-modal multi-site longitudinal birth cohort study designed to characterise emerging EFs in the first 1000 days of life in global majority settings. Most research to date has been conducted in highincome countries rather than low- and middle-income countries that comprise most of the world’s child population. We assert that understanding and supporting EF development has global importance, but this must be done with the understanding that EFs are skills that develop within the context of adaptation to one’s environment. As such, the Khula Study aims to understand which EF influences are common across cultures but also which are culture specific. We will address these questions by incorporating data …

Diabetes Technology & Therapeutics

Background: The Omnipod® 5 Automated Insulin Delivery (AID) System was shown to be safe and effective following 3 months of use in people with type 1 diabetes (T1D); however, data on the durability of these results are limited. This study evaluated the long-term safety and effectiveness of Omnipod 5 use in people with T1D during up to 2 years of use. Materials and Methods: After a 3-month single-arm, multicenter, pivotal trial in children (6–13.9 years) and adolescents/adults (14–70 years), participants could continue system use in an extension phase. HbA1c was measured every 3 months for up to 15 months; continuous glucose monitor metrics were collected for up to 2 years. Results: Participants (N = 224) completed median (interquartile range) 22.3 (21.7, 22.7) months of AID. HbA1c was reduced in the pivotal trial from 7.7% ± 0.9% in children and 7.2% ± 0.9% in adolescents/adults to 7.0% ± 0.6 …

Nature Astronomy

The search for life elsewhere involves variables across multiple scales in time and space, often nested hierarchically. We suggest that the emergence of artificial intelligence learning systems offers critically important ways to make progress.

On the 23rd November 2009, the LHC came alive for the experiments with first energy, proton-proton ie, for a centre collisions of mass delivered (CM) energy, for physics/s, of at 900 the GeV. beam On injection the 30th of the November world record the for beam highest energy energy was particle ramped-up collider to 1.18 in the TeV, world thus at setting/s=

Physical Review D

A search for quantum black holes in electron+ jet and muon+ jet invariant mass spectra is performed with 140 fb− 1 of data collected by the ATLAS detector in proton-proton collisions at s= 13 TeV at the Large Hadron Collider. The observed invariant mass spectrum of lepton+ jet pairs is consistent with Standard Model expectations. Upper limits are set at 95% confidence level on the production cross section times branching fractions for quantum black holes decaying into a lepton and a quark in a search region with invariant mass above 2.0 TeV. The resulting quantum black hole lower mass threshold limit is 9.2 TeV in the Arkani-Hamed-Dimopoulos-Dvali model, and 6.8 TeV in the Randall-Sundrum model.

arXiv preprint arXiv:2401.15755

Radiation tolerant, high speed and low power serializer ASIC is critical for optical link systems in particle physics experiments. Based on a commercial 0.25 um silicon-on-sapphire CMOS technology, we design a 16:1 serializer with 5 Gbps serial data rate. This ASIC has been submitted for fabrication. The post-layout simulation indicates the deterministic jitter is 54 ps (pk-pk) and random jitter is 3 ps (rms). The power consumption of the serializer is 500 mW. The design details and post layout simulation results are presented in this paper.

Physical Review D

A search for quantum black holes in electron+ jet and muon+ jet invariant mass spectra is performed with 140 fb− 1 of data collected by the ATLAS detector in proton-proton collisions at s= 13 TeV at the Large Hadron Collider. The observed invariant mass spectrum of lepton+ jet pairs is consistent with Standard Model expectations. Upper limits are set at 95% confidence level on the production cross section times branching fractions for quantum black holes decaying into a lepton and a quark in a search region with invariant mass above 2.0 TeV. The resulting quantum black hole lower mass threshold limit is 9.2 TeV in the Arkani-Hamed-Dimopoulos-Dvali model, and 6.8 TeV in the Randall-Sundrum model.

Physics Letters B

Semi-visible jets, with a significant contribution to the event's missing transverse momentum, can arise in strongly interacting dark sectors. This results in an event topology where one of the jets can be aligned with the direction of the missing transverse momentum. The first search for semi-visible jets produced via a t-channel mediator exchange is presented. The analysis uses proton-proton collisions with an integrated luminosity of 139 fb−1 and a centre-of-mass energy of 13 TeV, collected with the ATLAS detector during the Run 2 of the LHC. No excess over Standard Model predictions is observed. Assuming a coupling strength of unity between the mediator, a Standard Model quark and a dark quark, mediator masses up to 2.7 TeV are excluded at the 95% confidence level. Upper limits on the coupling strength are also derived.

Journal of Physics: Conference Series

Artificial Intelligence (AI) techniques are being used in general-purpose industrial computing systems. There is a great interest in expanding its use across other types of systems. However, they are not immediately applicable to embedded safety-critical systems. In particular, in spacecrafts, there are subsystems with high integrity requirements, which means that their failure could affect the overall behavior of the vehicle or even the loss of the complete mission. This paper deals with the use of some relevant AI techniques onboard space systems. Machine Learning and Neural Networks are potential techniques for these systems. The objective of this paper is to evaluate its applicability, select the most appropriate tools, and determine its feasibility to place onboard the satellite. Through the analysis of standards proposals, and a thermal estimation use case, we identify the issues, challenges, and guidelines to be …

Journal of the American College of Cardiology

BackgroundDual AV nodal physiology describes the ability of the AV node (AVN) to conduct using two distinct pathways, a fast AV nodal pathway and a slow pathway. Most commonly this results in AVNRT. Rarely, it can allow for a phenomenon known as 1: 2 AV conduction. 1: 2 AV conduction denotes one atrial impulse giving way to two ventricular depolarizations. This is often incorrectly interpreted as a tachyarrhythmia. Herein, we report a case of 1: 2 AV condition resulting in erroneous ICD recognition of VT and inappropriate ICD therapies.

Physics Letters B

The inclusive top-quark-pair production cross section σ t t¯ and its ratio to the Z-boson production cross section have been measured in proton–proton collisions at s= 13.6 TeV, using 29 fb− 1 of data collected in 2022 with the ATLAS experiment at the Large Hadron Collider. Using events with an opposite-charge electron-muon pair and b-tagged jets, and assuming Standard Model decays, the top-quark-pair production cross section is measured to be σ t t¯= 850±3 (stat.)±18 (syst.)±20 (lumi.) pb. The ratio of the t t¯ and the Z-boson production cross sections is also measured, where the Z-boson contribution is determined for inclusive e+ e− and μ+ μ− events in a fiducial phase space. The relative uncertainty on the ratio is reduced compared to the t t¯ cross section, thanks to the cancellation of several systematic uncertainties. The result for the ratio, R t t¯/Z= 1.145±0.003 (stat.)±0.021 (syst.)±0.002 (lumi.) is consistent …

Physical Review. B

The density fluctuation spectrum captures many fundamental properties of strange metals. Using momentum-resolved electron energy-loss spectroscopy (M-EELS), we recently showed that the density response of the strange metal Bi2Sr2CaCu2O8+x (Bi-2212) at large momentum, q, exhibits a constant-in-frequency continuum [Mitrano, PNAS 115, 5392 (2018); Husain, PRX 9, 041062 (2019)] reminiscent of the marginal Fermi liquid (MFL) hypothesis of the late 1980s [Varma, PRL 63, 1996 (1989)]. However, reconciling this observation with infrared (IR) optics experiments, which show a well-defined plasmon excitation at q ∼ 0, has been challenging. Here we report M-EELS measurements of Bi-2212 using 4× improved momentum resolution, allowing us to reach the optical limit. For momenta q < 0.04 r.l.u., the M-EELS data show a plasmon feature that is quantitatively consistent with IR optics. For q > 0.04 r.l.u., the spectra become incoherent with an MFL-like, constant-in-frequency form. We speculate that, at finite frequency, ω, and nonzero q, some attribute of this Planckian metal randomizes the probe electron, causing it to lose information about its own momentum.

Bulletin of the American Physical Society

G08. 00003: Interaction-driven Mott Transition with a non-degenerate Ground State in the Orbital Hatsugai-Kohmoto model

Inpainting has recently emerged as a valuable and interesting technology to employ in the analysis of medical imaging data, in particular brain MRI. A wide variety of methodologies for inpainting MRI have been proposed and demonstrated on tasks including anomaly detection.In this work we investigate the statistical relationship between inpainted brain structures and the amount of subject-specific conditioning information, i.e. the other areas of the image that are masked. In particular, we analyse the distribution of inpainting results when masking additional regions of the image, specifically the contra-lateral structure. This allows us to elucidate where in the brain the model is drawing information from, and in particular, what is the importance of hemispherical symmetry? Our experiments interrogate a diffusion inpainting model through analysing the inpainting of subcortical brain structures based on intensity and estimated area change. We demonstrate that some structures show a strong influence of symmetry in the conditioning of the inpainting process.

Physics Letters B

A search for non-resonant Higgs boson pair production, as predicted by the Standard Model, is presented, where one of the Higgs bosons decays via the H→ b b channel and the other via one of the H→ W W⁎/Z Z⁎/τ τ channels. The analysis selection requires events to have at least two b-tagged jets and exactly two leptons (electrons or muons) with opposite electric charge in the final state. Candidate events consistent with Higgs boson pair production are selected using a multi-class neural network discriminant. The analysis uses 139 fb− 1 of pp collision data recorded at a centre-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. An observed (expected) upper limit of 1.2 (0.9− 0.3+ 0.4) pb is set on the non-resonant Higgs boson pair production cross-section at 95% confidence level, which is equivalent to 40 (29− 9+ 14) times the value predicted in the Standard Model.

arXiv preprint arXiv:2401.05216

In the present paper we study some new classical Lorentz violating effects in planar electrodynamics due to the presence of stationary point-like field sources. Starting from the Carroll-Field-Jackiw model defined in (3+1) dimensions, which belongs to the electromagnetic CPT-odd sector of the Standard Model Extension (SME), we apply the dimensional reduction procedure obtaining a (2+1)-dimensional model that encompasses an electromagnetic sector composed of the Maxwell-Chern-Simons electrodynamics, a pure scalar sector described by a massless Klein-Gordon field, and a mixed sector where the background vector mediates contributions involving both the scalar and the gauge fields. For all the sectors of this planar theory, we explore some physical phenomena that arise from the interactions between external sources. Specifically, we obtain perturbative effects up to second order in the background vector related to the presence of both electric and scalar planar charges and Dirac points.

A search is conducted for new phenomena in events with a top quark pair and large missing transverse momentum, where the top quark pair is reconstructed in final states with one isolated electron or muon and multiple jets. The search is performed using the Large Hadron Collider proton--proton collision data sample at a centre-of-mass energy of TeV recorded by the ATLAS detector that corresponds to an integrated luminosity of 140 fb. An analysis based on neural network classifiers is optimised to search for directly produced pairs of supersymmetric partners of the top quark (stop), and to search for spin-0 mediators, produced in association with a pair of top quarks, that decay into dark-matter particles. In the stop search, the analysis is designed to target models in which the mass difference between the stop and the neutralino from the stop decay is close to the top quark mass. This new search is combined with previously published searches in final states with different lepton multiplicities. No significant excess above the Standard Model background is observed, and limits at 95% confidence level are set. Models with neutralinos with masses up to 570 GeV are excluded, while for small neutralino masses models are excluded for stop masses up to 1230 GeV. Scalar (pseudoscalar) dark matter mediator masses as large as 350 (370) GeV are excluded when the coupling strengths of the mediator to Standard Model and dark-matter particles are both set to one. At lower mediator masses, models with production cross-sections as small as 0.15 (0.16) times the nominal predictions are excluded. Results of this search are also used to set …

16th International Symposium on Radiative Corrections: Applications of Quantum Field Theory to Phenomenology

Matching and parton-shower accuracy - NASA/ADS Now on home page ads icon ads Enable full ADS view NASA/ADS Matching and parton-shower accuracy Scyboz, L. Abstract Publication: 16th International Symposium on Radiative Corrections: Applications of Quantum Field Theory to Phenomenology Pub Date: January 2024 Bibcode: 2024isrc.confE..66S full text sources Publisher | © The SAO/NASA Astrophysics Data System adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A NASA logo Smithsonian logo Resources About ADS ADS Help What's New Careers@ADS Social @adsabs ADS Blog Project Switch to full ADS Is ADS down? (or is it just me...) Smithsonian Institution Smithsonian Privacy Notice Smithsonian Terms of Use Smithsonian Astrophysical Observatory NASA …

arXiv preprint arXiv:2403.14763

Holography relates gravitational theories in five dimensions to four-dimensional quantum field theories in flat space. Under this map, the equation of state of the field theory is encoded in the black hole solutions of the gravitational theory. Solving the five-dimensional Einstein's equations to determine the equation of state is an algorithmic, direct problem. Determining the gravitational theory that gives rise to a prescribed equation of state is a much more challenging, inverse problem. We present a novel approach to solve this problem based on physics-informed neural networks. The resulting algorithm is not only data-driven but also informed by the physics of the Einstein's equations. We successfully apply it to theories with crossovers, first- and second-order phase transitions.

Scientific Reports

The digitization of natural history specimens and the popularization of citizen science are creating an unprecedented availability of large amounts of biodiversity data. These biodiversity inventories can be severely affected by species misidentification, a source of taxonomic uncertainty that is rarely acknowledged in biodiversity data management. For these reasons, taxonomists debate the use of online repositories to address biological questions at the species level. Hedera L. (ivies) provides an excellent case study as it is well represented in both herbaria and online repositories with thousands of records likely to be affected by high taxonomic uncertainty. We analyze the sources and extent of taxonomic errors in the identification of the European ivy species by reviewing herbarium specimens and find a high misidentification rate (18% on average), which varies between species (maximized in H. hibernica: 55%; H …

Journal of High Energy Physics

Differential cross-sections are measured for the production of four charged leptons in association with two jets. These measurements are sensitive to final states in which the jets are produced via the strong interaction as well as to the purely-electroweak vector boson scattering process. The analysis is performed using proton-proton collision data collected by ATLAS at= 13 TeV and with an integrated luminosity of 140 fb− 1. The data are corrected for the effects of detector inefficiency and resolution and are compared to state-of-the-art Monte Carlo event generator predictions. The differential cross-sections are used to search for anomalous weak-boson self-interactions that are induced by dimension-six and dimension-eight operators in Standard Model effective field theory.

Journal of High Energy Physics

A search for nonresonant Higgs boson pair production in the final state is performed using 140 fb− 1 of proton-proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. This analysis supersedes and expands upon the previous nonresonant ATLAS results in this final state based on the same data sample. The analysis strategy is optimised to probe anomalous values not only of the Higgs (H) boson self-coupling modifier κ λ but also of the quartic HHVV (V= W, Z) coupling modifier κ 2V. No significant excess above the expected background from Standard Model processes is observed. An observed upper limit μ HH< 4.0 is set at 95% confidence level on the Higgs boson pair production cross-section normalised to its Standard Model prediction. The 95% confidence intervals for the coupling modifiers are− 1.4< κ λ< 6.9 and− 0.5< κ 2V< 2.7, assuming …

Journal of High Energy Physics

A search for pair production of squarks or gluinos decaying via sleptons or weak bosons is reported. The search targets a final state with exactly two leptons with same-sign electric charge or at least three leptons without any charge requirement. The analysed data set corresponds to an integrated luminosity of 139 fb− 1 of proton-proton collisions collected at a centre-of-mass energy of 13 TeV with the ATLAS detector at the LHC. Multiple signal regions are defined, targeting several SUSY simplified models yielding the desired final states. A single control region is used to constrain the normalisation of the WZ+ jets background. No significant excess of events over the Standard Model expectation is observed. The results are interpreted in the context of several supersymmetric models featuring R-parity conservation or R-parity violation, yielding exclusion limits surpassing those from previous searches. In models …

Journal of High Energy Physics

Inclusive and differential cross-sections for the production of top quarks in association with a photon are measured with proton-proton collision data corresponding to an integrated luminosity of 139 fb− 1. The data were collected by the ATLAS detector at the LHC during Run 2 between 2015 and 2018 at a centre-of-mass energy of 13 TeV. The measurements are performed in a fiducial volume defined at parton level. Events with exactly one photon, one electron and one muon of opposite sign, and at least two jets, of which at least one is b-tagged, are selected. The fiducial cross-section is measured to be fb. Differential cross-sections as functions of several observables are compared with state-of-the-art Monte Carlo simulations and next-to-leading-order theoretical calculations. These include cross-sections as functions of photon kinematic variables, angular variables related to the photon and the leptons, and …

Journal of high energy physics

This paper presents a measurement of the production cross-section of a boson in association with - or -jets, in proton-proton collisions at TeV with the ATLAS experiment at the Large Hadron Collider using data corresponding to an integrated luminosity of 140 fb. Inclusive and differential cross-sections are measured for events containing a boson decaying into electrons or muons and produced in association with at least one -jet, at least one -jet, or at least two -jets with transverse momentum GeV and rapidity . Predictions from several Monte Carlo generators based on next-to-leading-order matrix elements interfaced with a parton-shower simulation, with different choices of flavour schemes for initial-state partons, are compared with the measured cross-sections. The results are also compared with novel predictions, based on infrared and collinear safe jet flavour dressing algorithms. Selected -jet observables, optimized for sensitivity to intrinsic-charm, are compared with benchmark models with different intrinsic-charm fractions.

Journal of High Energy Physics

New GeV-scale dark forces coupling predominantly to quarks offer novel signatures that can be produced directly and searched for at high-luminosity colliders. We compute the photon-proton and electron-proton cross sections for producing a GeV-scale gauge boson arising from a U (1) B gauge symmetry. Our calculation relies on vector meson dominance and a phenomenological model for diffractive scattering used for vector-meson photoproduction. The parameters of our phenomenological model are fixed by performing a Markov Chain Monte Carlo fit to existing exclusive photoproduction data for ω and ϕ mesons. Our approach can be generalized to other GeV-scale dark gauge forces.

Journal of high energy physics

Measurements of charged-particle production in pp, p–Pb, and Pb–Pb collisions in the toward, away, and transverse regions with the ALICE detector are discussed. These regions are defined event-by-event relative to the azimuthal direction of the charged trigger particle, which is the reconstructed particle with the largest transverse momentum in the range 8<< 15 GeV/c. The toward and away regions contain the primary and recoil jets, respectively; both regions are accompanied by the underlying event (UE). In contrast, the transverse region perpendicular to the direction of the trigger particle is dominated by the so-called UE dynamics, and includes also contributions from initial-and final-state radiation. The relative transverse activity classifier,, is used to group events according to their UE activity, where is the charged-particle multiplicity per event in the transverse region and is the mean …

Journal of High Energy Physics

We explain how equivariant localization may be applied to AdS/CFT to compute various BPS observables in gravity, such as central charges and conformal dimensions of chiral primary operators, without solving the supergravity equations. The key ingredient is that supersymmetric AdS solutions with an R-symmetry are equipped with a set of equivariantly closed forms. These may in turn be used to impose flux quantization and compute observables for supergravity solutions, using only topological information and the Berline-Vergne-Atiyah-Bott fixed point formula. We illustrate the formalism by considering AdS 5× M 6 and AdS 3× M 8 solutions of D= 11 supergravity. As well as recovering results for many classes of well-known supergravity solutions, without using any knowledge of their explicit form, we also compute central charges for which explicit supergravity solutions have not been constructed.

Journal of High Energy Physics

Differential cross-sections are measured for the production of four charged leptons in association with two jets. These measurements are sensitive to final states in which the jets are produced via the strong interaction as well as to the purely-electroweak vector boson scattering process. The analysis is performed using proton-proton collision data collected by ATLAS at= 13 TeV and with an integrated luminosity of 140 fb− 1. The data are corrected for the effects of detector inefficiency and resolution and are compared to state-of-the-art Monte Carlo event generator predictions. The differential cross-sections are used to search for anomalous weak-boson self-interactions that are induced by dimension-six and dimension-eight operators in Standard Model effective field theory.

Journal of High Energy Physics

A search for nonresonant Higgs boson pair production in the final state is performed using 140 fb− 1 of proton-proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. This analysis supersedes and expands upon the previous nonresonant ATLAS results in this final state based on the same data sample. The analysis strategy is optimised to probe anomalous values not only of the Higgs (H) boson self-coupling modifier κ λ but also of the quartic HHVV (V= W, Z) coupling modifier κ 2V. No significant excess above the expected background from Standard Model processes is observed. An observed upper limit μ HH< 4.0 is set at 95% confidence level on the Higgs boson pair production cross-section normalised to its Standard Model prediction. The 95% confidence intervals for the coupling modifiers are− 1.4< κ λ< 6.9 and− 0.5< κ 2V< 2.7, assuming …

Journal of High Energy Physics

A search for pair production of squarks or gluinos decaying via sleptons or weak bosons is reported. The search targets a final state with exactly two leptons with same-sign electric charge or at least three leptons without any charge requirement. The analysed data set corresponds to an integrated luminosity of 139 fb− 1 of proton-proton collisions collected at a centre-of-mass energy of 13 TeV with the ATLAS detector at the LHC. Multiple signal regions are defined, targeting several SUSY simplified models yielding the desired final states. A single control region is used to constrain the normalisation of the WZ+ jets background. No significant excess of events over the Standard Model expectation is observed. The results are interpreted in the context of several supersymmetric models featuring R-parity conservation or R-parity violation, yielding exclusion limits surpassing those from previous searches. In models …

Journal of high energy physics

Measurements of charged-particle production in pp, p–Pb, and Pb–Pb collisions in the toward, away, and transverse regions with the ALICE detector are discussed. These regions are defined event-by-event relative to the azimuthal direction of the charged trigger particle, which is the reconstructed particle with the largest transverse momentum in the range 8<< 15 GeV/c. The toward and away regions contain the primary and recoil jets, respectively; both regions are accompanied by the underlying event (UE). In contrast, the transverse region perpendicular to the direction of the trigger particle is dominated by the so-called UE dynamics, and includes also contributions from initial-and final-state radiation. The relative transverse activity classifier,, is used to group events according to their UE activity, where is the charged-particle multiplicity per event in the transverse region and is the mean …

Journal of High Energy Physics

Inclusive and differential cross-sections for the production of top quarks in association with a photon are measured with proton-proton collision data corresponding to an integrated luminosity of 139 fb− 1. The data were collected by the ATLAS detector at the LHC during Run 2 between 2015 and 2018 at a centre-of-mass energy of 13 TeV. The measurements are performed in a fiducial volume defined at parton level. Events with exactly one photon, one electron and one muon of opposite sign, and at least two jets, of which at least one is b-tagged, are selected. The fiducial cross-section is measured to be fb. Differential cross-sections as functions of several observables are compared with state-of-the-art Monte Carlo simulations and next-to-leading-order theoretical calculations. These include cross-sections as functions of photon kinematic variables, angular variables related to the photon and the leptons, and …

Journal of high energy physics

This paper presents a measurement of the production cross-section of a boson in association with - or -jets, in proton-proton collisions at TeV with the ATLAS experiment at the Large Hadron Collider using data corresponding to an integrated luminosity of 140 fb. Inclusive and differential cross-sections are measured for events containing a boson decaying into electrons or muons and produced in association with at least one -jet, at least one -jet, or at least two -jets with transverse momentum GeV and rapidity . Predictions from several Monte Carlo generators based on next-to-leading-order matrix elements interfaced with a parton-shower simulation, with different choices of flavour schemes for initial-state partons, are compared with the measured cross-sections. The results are also compared with novel predictions, based on infrared and collinear safe jet flavour dressing algorithms. Selected -jet observables, optimized for sensitivity to intrinsic-charm, are compared with benchmark models with different intrinsic-charm fractions.

Journal of High Energy Physics

Differential cross-sections are measured for the production of four charged leptons in association with two jets. These measurements are sensitive to final states in which the jets are produced via the strong interaction as well as to the purely-electroweak vector boson scattering process. The analysis is performed using proton-proton collision data collected by ATLAS at= 13 TeV and with an integrated luminosity of 140 fb− 1. The data are corrected for the effects of detector inefficiency and resolution and are compared to state-of-the-art Monte Carlo event generator predictions. The differential cross-sections are used to search for anomalous weak-boson self-interactions that are induced by dimension-six and dimension-eight operators in Standard Model effective field theory.

Journal of High Energy Physics

A search for nonresonant Higgs boson pair production in the final state is performed using 140 fb− 1 of proton-proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. This analysis supersedes and expands upon the previous nonresonant ATLAS results in this final state based on the same data sample. The analysis strategy is optimised to probe anomalous values not only of the Higgs (H) boson self-coupling modifier κ λ but also of the quartic HHVV (V= W, Z) coupling modifier κ 2V. No significant excess above the expected background from Standard Model processes is observed. An observed upper limit μ HH< 4.0 is set at 95% confidence level on the Higgs boson pair production cross-section normalised to its Standard Model prediction. The 95% confidence intervals for the coupling modifiers are− 1.4< κ λ< 6.9 and− 0.5< κ 2V< 2.7, assuming …

Journal of High Energy Physics

A search for pair production of squarks or gluinos decaying via sleptons or weak bosons is reported. The search targets a final state with exactly two leptons with same-sign electric charge or at least three leptons without any charge requirement. The analysed data set corresponds to an integrated luminosity of 139 fb− 1 of proton-proton collisions collected at a centre-of-mass energy of 13 TeV with the ATLAS detector at the LHC. Multiple signal regions are defined, targeting several SUSY simplified models yielding the desired final states. A single control region is used to constrain the normalisation of the WZ+ jets background. No significant excess of events over the Standard Model expectation is observed. The results are interpreted in the context of several supersymmetric models featuring R-parity conservation or R-parity violation, yielding exclusion limits surpassing those from previous searches. In models …

Journal of High Energy Physics

Inclusive and differential cross-sections for the production of top quarks in association with a photon are measured with proton-proton collision data corresponding to an integrated luminosity of 139 fb− 1. The data were collected by the ATLAS detector at the LHC during Run 2 between 2015 and 2018 at a centre-of-mass energy of 13 TeV. The measurements are performed in a fiducial volume defined at parton level. Events with exactly one photon, one electron and one muon of opposite sign, and at least two jets, of which at least one is b-tagged, are selected. The fiducial cross-section is measured to be fb. Differential cross-sections as functions of several observables are compared with state-of-the-art Monte Carlo simulations and next-to-leading-order theoretical calculations. These include cross-sections as functions of photon kinematic variables, angular variables related to the photon and the leptons, and …

Journal of high energy physics

This paper presents a measurement of the production cross-section of a boson in association with - or -jets, in proton-proton collisions at TeV with the ATLAS experiment at the Large Hadron Collider using data corresponding to an integrated luminosity of 140 fb. Inclusive and differential cross-sections are measured for events containing a boson decaying into electrons or muons and produced in association with at least one -jet, at least one -jet, or at least two -jets with transverse momentum GeV and rapidity . Predictions from several Monte Carlo generators based on next-to-leading-order matrix elements interfaced with a parton-shower simulation, with different choices of flavour schemes for initial-state partons, are compared with the measured cross-sections. The results are also compared with novel predictions, based on infrared and collinear safe jet flavour dressing algorithms. Selected -jet observables, optimized for sensitivity to intrinsic-charm, are compared with benchmark models with different intrinsic-charm fractions.

Journal of High Energy Physics

The flow of shape eigenmodes of the small fluctuation operator around BPS 2-vortex solutions is calculated, as a function of the intervortex separation 2d. For the rotationally-invariant 2-vortex, with d= 0, there are three discrete modes; the lowest is non-degenerate and the upper two are degenerate. As d increases, the degeneracy splits, with one eigenvalue increasing and entering the continuous spectrum, and the other decreasing and asymptotically coalescing with the lowest eigenvalue, where they jointly become the eigenvalue of the 1-vortex radial shape mode. The behaviour of the eigenvalues near d= 0 is clarified using a perturbative analysis, and also in light of the 2-vortex moduli space geometry.