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Introduction Malondialdehyde (MDA) is a product of polyunsaturated fatty acid peroxidation (Del Rio D, et al. A review of recent studies on MDA as toxic molecule and biological marker of oxidative stress. Nutr Metab Cardiovasc Dis. 2005;15:316-28). It is a biomarker of oxidative stress and is involved in the pathophysiology of schizophrenia (Goh et al. Asian J Psychiatr. 2022;67:102932). Schizofrenia is linked to disrupted oxidative balance and inflammation (Więdłocha et al. Brain Sci. 2023;13:490). Prior research has shown connections between biomarkers and circadian rhythms in schizophrenia (Morera & Abreu. Acta Physiol Scand. 2007;43:313-14) and diabetes type 2 (Kanabrocki EL, et al. Circadian variation in oxidative stress biomarkers in healthy and type II diabetic men. Chronobiol Int. 2002;19:423-39). To determinate if MDA levels have a role in schizophrenia and follow a circadian rhythm may be useful. Objectives The aim of our study is to compare diurnal and nocturnal MDA serum levels in patients in acute and stabilized phases of schizophrenia according to CIE-10 to find out if there are variations related with circadian rhythms Methods 47 patients were included in our study in two clinical phases: acute episode and stabilization. Blood samples were collected at 12:00h and at 00:00h. MDA serum levels were measured twice: when patients were decompensated (admission) and at clinical stabilization (discharge). The relationship between quantitative variables at both times was analysed by T-Student test Results There is no significative difference between night and day MDA levels in the acute phase of the schizophrenia (2.22±1.352 vs. 1.93±1.530, p

Introduction Antipsychotics are the primary class of drugs used to manage schizophrenia. These medications help control and reduce the severity of these symptoms, allowing individuals with schizophrenia to better function. On the other hand, rifampicin, used as treatment for tuberculosis, is a powerful inducer of several drug-metabolizing enzymes which have the potential to decrease the plasma levels of antipsychotics. Therefore, the presence of multiple pharmacokinetic interactions can alter how antipsychotics are metabolized, leading to a notable clinical impact when these medications are administered concurrently. Objectives The objective is to share valuable clinical experiences and insights to aid healthcare providers in making informed decisions when faced with the challenge of co-administering antipsychotics with rifampicin, ultimately ensuring the safety and efficacy of treatment for their patients. Methods It will be discussed a case of a 41-year-old woman with the diagnosis of schizophrenia under treatment with paliperidone palmitate and clozapine who had a sudden relapse after starting treatment for latent tuberculosis with rifampicin as a framework for a literature review based off Pubmed. Results The antituberculosis drug rifampicin induces drug-metabolizing enzymes in the liver, having the greatest effects on the expression of cytochrome P450 (CYP3A4) and therefore can lead to a decrease in the plasma levels of antipsychotic medications that also rely on these pathways for clearance. In this particular case, although specific data on clozapine and paliperidone concentrations were not reported, fluctuations in symptomatology following rifampicin introduction were probably explained by an inducing effect of this drug on their metabolism. So, when initiating rifampicin treatment and when discontinuing it, clinicians should carefully assess the dosages of any concomitant medications that may potentially interact with rifampicin. To ensure effective therapy during rifampicin treatment, it is crucial to monitor both the patient’s clinical response and their blood drug concentrations, making dosage adjustments as necessary. Conclusions This case report offers valuable guidance to clinicians on safely and effectively managing drug interactions between antipsychotic medications and rifampicin, ensuring the well-being of their patients during treatment. The co-administration of these medications lacks robust clinical evidence, and notably, there is insufficient data regarding its impact on plasma antipsychotic levels, a crucial factor in determining clinical effectiveness. Disclosure of Interest None Declared

Introduction In the context of treatment-resistant bipolar depression, the use of neuromodulation techniques, notably transcranial magnetic stimulation (TMS), has been on the rise, particularly in the treatment of mood disorders. TMS involves the generation of a strong pulsed magnetic field through an electromagnet placed near the skull, thereby inducing an electrical field capable of depolarizing nerve cell membranes (Dolberg et al., 2001). The magnetic nature of TMS carries advantages compared to direct electric stimulation, such as fewer side effects, reduced invasiveness, and precise targeting. Nevertheless, it is not without its risks. Reported concerns include the induction of manic or hypomanic states, particularly in individuals with bipolar disorder, as well as unipolar depression (Sakkas et al., 2003; Ozten et al.,2013; Knox et al 2021). Objectives This review aims to assess the safety and viability of TMS as a therapeutic option and how to best optimize its clinical use. Methods A comprehensive literature review was conducted utilizing resources from Pubmed, Researchgate, and Google Scholar. Results Despite some inconsistencies and potential confounding factors, our findings suggest that TMS may not significantly elevate the risk of manic switching, especially when compared to conventional treatments like antidepressants. However, it may potentially induce manic episodes, particularly when used as monotherapy or in combination with other treatments. Variables such as treatment protocol and prior response to medication may contribute to mood switching risk. Proposed safety measures include personalized protocol design, close patient monitoring and the combination with mood-stabilizing medication. Conclusions Transcranial magnetic stimulation has been associated with manic and hypomanic episodes in mood disorder patients. While the evidence remains limited, it appears that certain individuals may be more susceptible to mood switching. Nevertheless, further research is needed to better elucidate variables influencing mood switching during TMS treatment and to develop effective preventative measures, especially for patients already predisposed to manic switching. Disclosure of Interest None Declared

Introduction In today’s world of global migration and cultural diversity, mental health care grapples with persistent challenges. Despite efforts to promote cultural competency and person-centred approaches, it’s vital to delve into the issues surrounding cultural differences and linguistic diversity in mental health care. This exploration highlights the complexities where culture, language, and healthcare intersect (Brisset et al., 2014; Desai et al., 2021). Objectives Our aim is to analyse cultural and linguistic barriers in mental health care for migrants and assess their impact on access and quality of care. Methods Literature review, drawing from sources such as PubMed, ResearchGate, and Google Scholar. This review will be framed around the case of a 34-year-old man from Bangladesh, who has been residing in Lisbon for a year. His clinical presentation includes depressive symptoms, disorganized behaviour, and psychotic manifestations, such as persecutory delusions. He does not speak Portuguese or English, thereby limiting his access to essential mental health treatment services. Through this review, we intend to elucidate the intricate dynamics surrounding cultural and linguistic barriers in mental health care. Results Migrants from diverse backgrounds face many challenges, including the loss of homes, livelihoods, and family, often leading to mental health issues like depression, anxiety, and post-traumatic stress disorder. Two primary challenges include adapting to a new life and experiencing discrimination and marginalization (Amri et al., 2013; Satinsky et al., 2019). Social stigma and mistrust hinder access to mental health services. Limited culturally competent services widen the gap between mental health needs and help-seeking attitudes. Language barriers significantly contribute to disparities in access to services (Amri et al., 2013). Additionally, mental health care providers’ organizational culture often prioritizes ‘ideal’ patients who are native speakers, favouring individual-oriented treatment over community-focused care (Desai et al., 2021). To address these barriers effectively, it is crucial to employ specific strategies. The Multi-Phase Model of Psychotherapy, Social Justice, and Human Rights (MPM) equips mental health counsellors to better serve immigrant communities while addressing social stigma. This comprehensive framework comprises five phases of intervention: psychoeducation, culturally responsive service delivery, cultural orientation, collaboration with local healers, and connecting patients to essential resources (Amri et al., 2013). Additionally, practitioners should receive training in effective collaboration with interpreters to provide multilingual healthcare (Brisset et al., 2014). Conclusions Addressing cultural and linguistic barriers in mental health care is vital. The Multi-Phase Model of Psychotherapy offers a promising approach, while collaboration with interpreters remains essential. Disclosure of Interest None Declared

Introduction Lithium is a well-established mood stabilizer used in the management of bipolar disorder, that is generally well-tolerated; however, it is associated with rare but potentially severe neurological side effects. Lithium-induced encephalopathy is characterized by a spectrum of symptoms, ranging from subtle cognitive deficits to severe manifestations such as altered mental status to overt delirium, seizures and coma. Risk factors include advanced age, concomitant medication and underlying renal impairment. This symptoms do not consistentely correlate with lithium concentrations. Objectives This abstract aims to provide an overview of the clinical characteristics, underlying mechanisms, and management of lithium-induced encephalopathy. Methods We discuss a case of a 62-years-old woman diagnosed with bipolar disorder under treatment with lithium and olanzapine, without recent changes of posology. She presented to emergency department with subacute and fluctuating neuropsychiatric symptoms, including confusion, disorientation in time and space, complex visual hallucinations, delusional ideas, alteration in memory and logic thinking, dysarthria and dyspraxia. Neuroimaging showed no structural abnormalities, blood tests were normal and serum lithium levels were within the therapeutic range (0.8 mEq/L). Upon discontinuation of lithium, the patient exhibited a gradual resolution of symptoms. We conducted a comprehensive search of medical databases, including PubMed, to identify relevant articles related to lithium encephalopathy published up to September 2023. Results This case challenges the conventionally established threshold of elevated serum lithium levels in the development of encephalopathy. The underlying pathophysiology is complex and multifactorial, with proposed mechanisms including alterations in neurotransmitter balance, oxidative stress, mitochondrial dysfunction and individual susceptibility to idiosyncratic reactions. Early diagnosis is challenging, necessitating a high clinical suspicion, neuroimaging and exclusion of other etiologies. Management strategies involve discontinuation of lithium, even when serum lithium levels are within the therapeutic range, supportive care, and, in severe cases, hemodialysis to reduce lithium levels rapidly. Conclusions Clinicians should maintain a high index of suspicion of lithium-induced encephalopathy, especially in patients presenting with neurological symptoms while on lithium treatment. Early recognition and intervention are essential for minimizing morbidity and preventing potentially irreversible neurological damage. Further research is needed to better understand the precise mechanisms underlying it, risk factors and to refine treatment strategies. Disclosure of Interest None Declared

Results are presented for the measurement of large-scale anisotropies in the arrival directions of ultra–high-energy cosmic rays detected at the Pierre Auger Observatory during 19 yr of operation, prior to AugerPrime, the upgrade of the observatory. The 3D dipole amplitude and direction are reconstructed above 4 EeV in four energy bins. Besides the established dipolar anisotropy in R.A. above 8 EeV, the Fourier amplitude of the 8–16 EeV energy bin is now also above the 5 σ discovery level. No time variation of the dipole moment above 8 EeV is found, setting an upper limit to the rate of change of such variations of 0.3% yr ^−1 at the 95% confidence level. Additionally, the results for the angular power spectrum are shown, demonstrating no other statistically significant multipoles. The results for the equatorial dipole component down to 0.03 EeV are presented, using for the first time a data set obtained with a trigger that has been optimized for lower energies. Finally, model predictions are discussed and compared with observations, based on two source emission scenarios obtained in the combined fit of spectrum and composition above 0.6 EeV.

In 2021 JET exploited its unique capabilities to operate with T and D–T fuel with an ITER-like Be/W wall (JET-ILW). This second major JET D–T campaign (DTE2), after DTE1 in 1997, represented the culmination of a series of JET enhancements—new fusion diagnostics, new T injection capabilities, refurbishment of the T plant, increased auxiliary heating, in-vessel calibration of 14 MeV neutron yield monitors—as well as significant advances in plasma theory and modelling in the fusion community. DTE2 was complemented by a sequence of isotope physics campaigns encompassing operation in pure tritium at high T-NBI power. Carefully conducted for safe operation with tritium, the new T and D–T experiments used 1 kg of T (vs 100 g in DTE1), yielding the most fusion reactor relevant D–T plasmas to date and expanding our understanding of isotopes and D–T mixture physics. Furthermore, since the JET T and DTE2 campaigns occurred almost 25 years after the last major D–T tokamak experiment, it was also a strategic goal of the European fusion programme to refresh operational experience of a nuclear tokamak to prepare staff for ITER operation. The key physics results of the JET T and DTE2 experiments, carried out within the EUROfusion JET1 work package, are reported in this paper. Progress in the technological exploitation of JET D–T operations, development and validation of nuclear codes, neutronic tools and techniques for ITER operations carried out by EUROfusion (started within the Horizon 2020 Framework Programme and continuing under the Horizon Europe FP) are reported in (Litaudon et al Nucl. Fusion accepted), while JET experience on T and D–T operations is presented in (King et al Nucl. Fusion submitted).

Introduction S100B is a calcium-binding astrocyte-specific cytokine, that is considered a biomarker of neurodegeneration; which may be involved in the imbalance of the inflammatory response observed in several brain disorders, including major depression and schizophrenia. Two meta-analyses have reported higher serum levels of S100B in patients with schizophrenia respect to healthy controls. Different studies have described circadian and seasonal variations of biological variables, such as melatonin or cortisol. It has been reported that there is not circadian rhythm of S100B blood levels in healthy subjects. However, it is not known whether there are circadian oscillations in S100B blood concentrations in patients with schizophrenia. Objectives The aim of this study is to describe S100B serum levels in patients with schizophrenia and to analyse whether they follow a circadian rhythm. Methods Our sample consists in 47 patients in acute phase and stabilized status. Blood samples were collected at 12:00 and 00:00 hours by venipuncture. Serum levels of Protein S100B were measured three times: at admission, discharge and three months after discharge. Protein S100B was measured by means of ELISA (Enzyme-linked immunosorbent assay) techniques. Results 12:00 24:00 P ADMISSION 132,95±199,27 85,85±121,44 0,004 DISCHARGE 73,65±71,744 75,80±123,628 0,070 CONTROL 43,49±34,60 40,14±23,08 0,47 P global P Admission Vs. Discharge P Admission Vs. Control P Discharge Vs. Control 0,97 There is a significance difference between 12:00 and 24:00 at admission for the Protein S100B.However, these difference did not occur at discharge and at three months after discharge.It can be interpreted as there is a circadian rhythm of Protein S100B when the patient has got a psychotic outbreak and disappears at discharge and when is psychopathologically stable. Conclusions With respect to our results we can hypothesize that schizophrenic patients in acute relapse present circadian S100B rhythm that is not present when the patients are clinically stable.Furthermore, the decrease of serum protein S100B levels at discharge is indicative of a reduction of the cerebral inflammation, thus it can be a biomarker of cerebral inflammation and this reduction can be the effect of the treatment. Finally, its circadianity could be a guide of this process and clinical improvement. Disclosure of Interest None Declared

Introduction It has been reported an inflammatory state in schizophrenia, with altered levels of some cytokines (Zhou et al. Cytokine 2021; 141:155441). Recent publications have shown the importance of IL- 33, a member of the IL-1 cytokine family which acts as an alarmin (Han et al. Neurosci Bull 2011; 27, 351-357). The role of this cytokine as a biomarker has been investigated in schizophrenia (Koricanac et al. Front Psychiatry 2022; 13, 925757). However, results are controversial. Some studies have not found significant associations between IL-33 and chronic schizophrenia (Campos-Carli et al. Compr Psychiatry 2017; 74 96-101), while other papers have reported increased levels (Kozlowska et. al. J Psychiatr Res. 2021; 138 380-387). In all these studies, levels of IL-33 were measured in a single daily measure, so that it has not been studied if IL-33 has changes during hospitalization. Objectives To study the serum level of IL-33 at 12:00 and 00:00 hours in schizophrenia patients at admission and before hospital discharge. Methods Fifteen inpatients with diagnosis of paranoid schizophrenia according to ICD-10 criteria were studied. Patients were hospitalized at the University Hospital of the Canary Islands psychiatric ward because of an acute relapse. A total of four blood samples were taken from each patient: at 12:00 and 00:00 hours the day after admission and at 12:00 and 00:00 hours the day before discharge. Serum IL-33 levels were measured by ELISA techniques. Daytime and nighttime IL-33 serum levels at admission and discharge were compared using a non-parametric Wilcoxon signed-rank test. Results In table 1 the results of the comparison of IL-33 at admission and discharge are presented. There is a significant reduction of IL-33 levels at 00:00 h. at discharge in comparison with the IL-33 levels at 00:00 h. at admission (p=0.028). No other statistically significant differences were observed. Serum IL-33 AdmissionMean±sd DischargeMean±sd Z Pvalue 12:00 h. 191.0±348.7 247.0±378.2 -0.166 0.868 00:00 h. 218.8±370.3 153.6±275.7 -2.203 0.028 Conclusions The decrease of serum IL-33 at 00:00 at discharge compared to the 00:00 IL-33 serum level at admission points to the utility of this biomarker as a surrogate of brain inflammation. Disclosure of Interest None Declared

Introduction Day-night changes in several molecules are studied as biomarkers of circadian rhytms (Morera-Fumero, A. L. et al. Progress in Neuro-Psychopharmacology and Biological Psychiatry 2017; 75 207-212). Circadian rhythmicity of the pituitary-thyroid axis has been proven in healthy individuals, with a Thyroid Stimulating Hormone (TSH) peak in serum around midnight and peaks during day hours (Bellastella, G. et al. Life 2021; 11(5), 426). A recent meta-analysis has reported differences in serum TSH levels between first-episode psychosis and multiple-episode schizophrenia (Misiak, B. et al. Progress in Neuro-Psychopharmacology and Biological Psychiatry 2021; 111, 110402). However, studies assessing quantitative circadian variations on TSH serum in schizophrenic patients are scant. Objectives Comparing serum TSH levels at two different times of the day (12:00 and 24:00 hours) and the differences between the acute (hospital admission) and recovered phase (hospital discharge) of the disease. Methods Fourteen male patients (age 26,8±9,3 years) with the diagnosis of paranoid schizophrenia psychosis according to the DSM-IV partake in the study. Patients were admitted to the University Hospital of the Canary Islands psychiatric room because of acute relapse. Blood samples were taken in the first 24 h of admission and at 24 h. before discharge. All patients gave written consent to participate in the research study. Serum TSH was determined by ELISA methods. Paired sample t-tests were performed between TSH serum levels at admission and discharge at 12:00 and 24:00 hours. Statistical analyses were performed using IBM® SPSS® Statistics 25 software for MAC (IBM Corporation 1989, 2017). Results There were statistical differences between the 12:00 h and the 24:00 h of the TSH serum levels at admission (12:00: 145,856±156,961vs. 00:00: 192,006± 122,757, p = 0.04); TSH discharge, (12:00: 134,483±72,882vs 00:00: 244,214±148,697, p = 0.002). There were no statistical differences between the 12:00 TSH levels at admission and discharge (145,856±156,961 vs. 134,483± 72,882, p = 0.66). The 24:00 h comparison of TSH levels neither elicited significant results (admission: 192,006±122,757 vs. discharge: 244,214± 148,697, p = 0.15). Conclusions Schizophrenic patients undergo TSH serum changes in a circadian pattern during the acute and stable phases of the disease; nevertheless, they experience smaller deviations during the acute phase. Higher levels of TSH were observed around midnight, as it happens in healthy individuals, with higher peaks during the stable phase compared to the acute one. Disclosure of Interest None Declared

Abstract We present a measurement of the cosmic-ray spectrum above 100 PeV using the part of the surface detector of the Pierre Auger Observatory that has a spacing of 750 m. An inflection of the spectrum is observed, confirming the presence of the so-called second-knee feature. The spectrum is then combined with that of the 1500 m array to produce a single measurement of the flux, linking this spectral feature with the three additional breaks at the highest energies. The combined spectrum, with an energy scale set calorimetrically via fluorescence telescopes and using a single detector type, results in the most statistically and systematically precise measurement of spectral breaks yet obtained. These measurements are critical for furthering our understanding of the highest energy cosmic rays.

This essay reports on engaging academic and community partners whose positionalities spanned diverse lived experiences and power structures. Using groundwork from several literatures, we reflect on developing, nurturing, repairing, and expanding a container as a critically reflective space for experimenting with new ways of being and doing. A well-curated and nurtured container creates processes and spaces where group members feel they belong; they commit to practice a shared set of agreements, and work through interpersonal and organizational conflict that will inevitably arise. The container can be an instrument for identity, organizational, and tactical boundary spanning. As a microsystem, a container can mobilize collective engagement when team members reflect diverse identities, hierarchies, and roles within the academic system and partnering communities. Theorizing the container as an opportunity structure for boundary spanning may help those advancing diversity, equity, inclusion, and justice (DEIJ) within academic land-grant institutions, university-community collaboratives, and community-based organizations.

A search for heavy right-handed Majorana neutrinos is performed with the ATLAS detector at the CERN Large Hadron Collider, using the 140  fb−1 of proton–proton collision data at s=13  TeV collected during Run 2. This search targets tt¯ production, in which both top quarks decay into a bottom quark and a W boson, where one of the W bosons decays hadronically and the other decays into an electron or muon and a heavy neutral lepton. The heavy neutral lepton is identified through a decay into an electron or muon and another W boson, resulting in a pair of same-charge same-flavor leptons in the final state. This paper presents the first search for heavy neutral leptons in the mass range of 15–75 GeV using tt¯ events. No significant excess is observed over the background expectation, and upper limits are placed on the signal cross sections. Assuming a benchmark scenario of the phenomenological type-I seesaw model, these cross section limits are then translated into upper limits on the mixing parameters of the heavy Majorana neutrino with Standard Model neutrinos. © 2024 CERN, for the ATLAS Collaboration 2024 CERN

Charged particle reconstruction in the presence of many simultaneous proton–proton (pp) collisions in the LHC is a challenging task for the ATLAS experiment’s reconstruction software due to the combinatorial complexity. This paper describes the major changes made to adapt the software to reconstruct high-activity collisions with an average of 50 or more simultaneous pp interactions per bunch crossing (pile-up) promptly using the available computing resources. The performance of the key components of the track reconstruction chain and its dependence on pile-up are evaluated, and the improvement achieved compared to the previous software version is quantified. For events with an average of 60pp collisions per bunch crossing, the updated track reconstruction is twice as fast as the previous version, without significant reduction in reconstruction efficiency and while reducing the rate of combinatorial fake tracks by more than a factor two.

The need for large-scale production of highly accurate simulated event samples for the extensive physics programme of the ATLAS experiment at the Large Hadron Collider motivates the development of new simulation techniques. Building on the recent success of deep learning algorithms, variational autoencoders and generative adversarial networks are investigated for modelling the response of the central region of the ATLAS electromagnetic calorimeter to photons of various energies. The properties of synthesised showers are compared with showers from a full detector simulation using geant4. Both variational autoencoders and generative adversarial networks are capable of quickly simulating electromagnetic showers with correct total energies and stochasticity, though the modelling of some shower shape distributions requires more refinement. This feasibility study demonstrates the potential of using such algorithms for ATLAS fast calorimeter simulation in the future and shows a possible way to complement current simulation techniques.

A search is presented for direct pair production of the stop, the supersymmetric partner of the top quark, in a decay through an R-parity violating coupling to a charged lepton and a b-quark. The dataset corresponds to an integrated luminosity of 140  fb−1 of proton-proton collisions at a center-of-mass energy of s=13  TeV collected between 2015 and 2018 by the ATLAS detector at the LHC. The final state has two charged leptons (electrons or muons) and two b-jets. The results of the search are interpreted in the context of a Minimal Supersymmetric Standard Model with an additional B−L gauge symmetry that is spontaneously broken. No significant excess is observed over the Standard Model background, and exclusion limits on stop pair production are set at 95% confidence level. The corresponding lower limits on the stop mass for 100% branching ratios to a b-quark and an electron, muon, or tau-lepton are 1.9 TeV, 1.8 TeV and 800 GeV, respectively, extending the reach of previous LHC searches. © 2024 CERN, for the ATLAS Collaboration 2024 CERN

A hallmark of fetal alcohol spectrum disorders (FASD) is neurobehavioral deficits that still do not have effective treatment. Here, we present that reduction of Apolipoprotein E (APOE) is critically involved in neurobehavioral deficits in FASD. We show that prenatal alcohol exposure (PAE) changes chromatin accessibility of Apoe locus, and causes reduction of APOE levels in both the brain and peripheral blood in postnatal mice. Of note, postnatal administration of an APOE receptor agonist (APOE-RA) mitigates motor learning deficits and anxiety in those mice. Several molecular and electrophysiological properties essential for learning, which are altered by PAE, are restored by APOE-RA. Our human genome-wide association study further reveals that the interaction of PAE and a single nucleotide polymorphism in the APOE enhancer which chromatin is closed by PAE in mice is associated with lower scores in the delayed matching-to-sample task in children. APOE in the plasma is also reduced in PAE children, and the reduced level is associated with their lower cognitive performance. These findings suggest that controlling the APOE level can serve as an effective treatment for neurobehavioral deficits in FASD.

A search for long-lived particles (LLPs) using 140  fb^{-1} of pp collision data with sqrt[s]=13  TeV recorded by the ATLAS experiment at the LHC is presented. The search targets LLPs with masses between 5 and 55 GeV that decay hadronically in the ATLAS inner detector. Benchmark models with LLP pair production from exotic decays of the Higgs boson and models featuring long-lived axionlike particles (ALPs) are considered. No significant excess above the expected background is observed. Upper limits are placed on the branching ratio of the Higgs boson to pairs of LLPs, the cross section for ALPs produced in association with a vector boson, and, for the first time, on the branching ratio of the top quark to an ALP and a u/c quark.

A search for the exclusive hadronic decays W^{±}→π^{±}γ, W^{±}→K^{±}γ, and W^{±}→ρ^{±}γ is performed using up to 140  fb^{-1} of proton-proton collisions recorded with the ATLAS detector at a center-of-mass energy of sqrt[s]=13  TeV. If observed, these rare processes would provide a unique test bench for the quantum chromodynamics factorization formalism used to calculate cross sections at colliders. Additionally, at future colliders, these decays could offer a new way to measure the W boson mass through fully reconstructed decay products. The search results in the most stringent upper limits to date on the branching fractions B(W^{±}→π^{±}γ)

The associated production of Higgs and W bosons via vector-boson fusion is highly sensitive to the relative sign of the Higgs boson couplings to W and Z bosons. In this Letter, two searches for this process are presented, using 140  fb−1 of proton-proton collision data at s=13  TeV recorded by the ATLAS detector at the LHC. The first search targets scenarios with opposite-sign couplings of the W and Z bosons to the Higgs boson, while the second targets standard model-like scenarios with same-sign couplings. Both analyses consider Higgs boson decays into a pair of b quarks and W boson decays with an electron or muon. The data exclude the opposite-sign coupling hypothesis with a significance beyond 5σ, and the observed (expected) upper limit set on the cross section for vector-boson fusion WH production is 9.0 (8.7) times the standard model value at 95% confidence level. © 2024 CERN, for the ATLAS Collaboration 2024 CERN

This Letter presents a differential cross-section measurement of Lund subjet multiplicities, suitable for testing current and future parton shower Monte Carlo algorithms. This measurement is made in dijet events in 140 fb−1 of s=13 TeV proton–proton collision data collected with the ATLAS detector at CERN's Large Hadron Collider. The data are unfolded to account for acceptance and detector-related effects, and are then compared with several Monte Carlo models and to recent resummed analytical calculations. The experimental precision achieved in the measurement allows tests of higher-order effects in QCD predictions. Most predictions fail to accurately describe the measured data, particularly at large values of jet transverse momentum accessible at the Large Hadron Collider, indicating the measurement's utility as an input to future parton shower developments and other studies probing fundamental properties of QCD and the production of hadronic final states up to the TeV-scale.

Measurements of jet cross-section ratios between inclusive bins of jet multiplicity are performed in 140  fb−1 of proton-proton collisions with s=13  TeV center-of-mass energy, recorded with the ATLAS detector at CERN’s Large Hadron Collider. These ratios are constructed from double-differential cross-section measurements that are made in bins of jet multiplicity and other observables that are sensitive the energy scale and angular distribution of radiation due to the strong interaction in the final state. Additionally, the scalar sum of the two leading jets’ transverse momenta is measured triple differentially, in bins of the third jet’s transverse momentum and of jet multiplicity. These measurements are unfolded to account for acceptance and detector-related effects. The measured distributions are used to construct ratios of the inclusive jet-multiplicity bins, which have been shown to be sensitive to the strong coupling αS while being less sensitive than other observables to systematic uncertainties and parton distribution functions. The measured distributions are compared with state-of-the-art QCD calculations, including next-to-next-to-leading-order predictions for two- and three-jet events. These predictions are generally found to model the data well and perform best in bins with a modest requirement on the third jet’s transverse momentum. Significant differences between data and Monte Carlo predictions are observed in events with large rapidity gaps and invariant masses of the leading jet pair. Studies leading to reduced jet energy scale uncertainties significantly improve the precision of this work and are documented herein. © 2024 CERN, for the ATLAS Collaboration 2024 CERN

This paper describes measurements of the transverse momentum spectra of W and Z bosons produced in proton–proton collisions at centre-of-mass energies of s=5.02 TeV and s=13 TeV with the ATLAS experiment at the Large Hadron Collider. Measurements are performed in the electron and muon channels, W→ℓν and Z→ℓℓ (ℓ=e or μ), and for W events further separated by charge. The data were collected in 2017 and 2018, in dedicated runs with reduced instantaneous luminosity, and correspond to 255 and 338 pb-1 at s=5.02 TeV and 13 TeV, respectively. These conditions optimise the reconstruction of the W-boson transverse momentum. The distributions observed in the electron and muon channels are unfolded, combined, and compared to QCD calculations based on parton shower Monte Carlo event generators and analytical resummation. The description of the transverse momentum distributions by Monte Carlo event generators is imperfect and shows significant differences largely common to W-, W+ and Z production. The agreement is better at s=5.02 TeV, especially for predictions that were tuned to Z production data at s=7 TeV. Higher-order, resummed predictions based on DYTurbo generally match the data best across the spectra. Distribution ratios are also presented and test the understanding of differences between the production processes.

The inclusive cross section for the production of a single top quark in association with a W boson is measured using 140  fb−1 of proton-proton collision data collected with the ATLAS detector at s=13  TeV. Events containing two charged leptons and at least one jet identified as originating from a b-quark are selected. A multivariate discriminant is constructed to separate the tW signal from the tt¯ background. The cross section is extracted using a profile likelihood fit to the signal and control regions and it is measured to be σtW=75−14+15  pb, in good agreement with the Standard Model prediction. The measured cross section is used to extract a value for the left-handed form factor at the Wtb vertex times the Cabibbo-Kobayashi-Maskawa matrix element |fLVVtb| of 0.97±0.10. © 2024 CERN, for the ATLAS Collaboration 2024 CERN

This report reviews the published results of searches for possible additional scalar particles and exotic decays of the Higgs boson performed by the ATLAS Collaboration using up to 140 fb−1 of 13 TeV proton–proton collision data collected during Run 2 of the Large Hadron Collider. Key results are examined, and observed excesses, while never statistically compelling, are noted. Constraints are placed on parameters of several models which extend the Standard Model, for example by adding one or more singlet or doublet fields, or offering exotic Higgs boson decay channels. Summaries of new searches as well as extensions of previous searches are discussed. These new results have a wider reach or attain stronger exclusion limits. New experimental techniques that were developed for these searches are highlighted. Search channels which have not yet been examined are also listed, as these provide insight into possible future areas of exploration.

This paper reports a summary of searches for a fermionic dark matter candidate in the context of theoretical models characterised by a mediator particle exchange in the s-channel. The data sample considered consists of pp collisions delivered by the Large Hadron Collider during its Run 2 at a centre-of-mass energy of s=13TeV and recorded by the ATLAS detector, corresponding to up to 140 fb-1. The interpretations of the results are based on simplified models where the new mediator particles can be spin-0, with scalar or pseudo-scalar couplings to fermions, or spin-1, with vector or axial-vector couplings to fermions. Exclusion limits are obtained from various searches characterised by final states with resonant production of Standard Model particles, or production of Standard Model particles in association with large missing transverse momentum.

Abstract: The ratio of branching ratios of the W boson to muons and electrons, $$R^{\,\mu /e}_W={{\mathcal {B}}(W\rightarrow \mu u )}$$ R W μ / e = B ( W → μ ν ) /$${{\mathcal {B}}(W\rightarrow eu )}$$ B ( W → e ν ) , has been measured using $$140\,\text{ fb}^{-1}\,$$ 140 fb - 1 of pp collision data at $$\sqrt{s}=13$$ s = 13  $$\text {T}\text {e}\hspace{-1.00006pt}\text {V}$$ Te V collected with the ATLAS detector at the LHC, probing the universality of lepton couplings. The ratio is obtained from measurements of the $$t\bar{t}$$ t t ¯ production cross-section in the ee, $$e\mu $$ e μ and $$\mu \mu $$ μ μ dilepton final states. To reduce systematic uncertainties, it is normalised by the square root of the corresponding ratio $$R^{\,\mu \mu /ee}_Z$$ R Z μ μ / e e for the Z boson measured in inclusive $$Z\rightarrow ee$$ Z → e e and $$Z\rightarrow \mu \mu $$ Z → μ μ events. By using the precise value of $$R^{\,\mu \mu /ee}_Z$$ R Z μ μ / e e determined from $$e^+e^-$$ e + e - colliders, the ratio $$R^{\,\mu /e}_W$$ R W μ / e is determined to be $$\begin{aligned} R^{\,\mu /e}_W&= 0.9995\pm 0.0022\,\mathrm {(stat)}\,\pm 0.0036\,\mathrm {(syst)}\\ &\quad \pm 0.0014\,\mathrm {(ext)} . \end{aligned}$$ R W μ / e = 0.9995 ± 0.0022 ( stat ) ± 0.0036 ( syst ) ± 0.0014 ( ext ) . The three uncertainties correspond to data statistics, experimental systematics and the external measurement of $$R^{\,\mu \mu /ee}_Z$$ R Z μ μ / e e , giving a total uncertainty of 0.0045, and confirming the Standard Model assumption of lepton flavour universality in W-boson decays at the 0.5% level.

Abstract: Pixel sensors in 3D technology equip the outer ends of the staves of the Insertable B Layer (IBL), the innermost layer of the ATLAS Pixel Detector, which was installed before the start of LHC Run 2 in 2015. 3D pixel sensors are expected to exhibit more tolerance to radiation damage and are the technology of choice for the innermost layer in the ATLAS tracker upgrade for the HL-LHC programme. While the LHC has delivered an integrated luminosity of  ≃ 235 fb-1 since the start of Run 2, the 3D sensors have received a non-ionising energy deposition corresponding to a fluence of ≃ 8.5 × 1014 1 MeV neutron-equivalent cm-2 averaged over the sensor area. This paper presents results of measurements of the 3D pixel sensors' response during Run 2 and the first two years of Run 3, with predictions of its evolution until the end of Run 3 in 2025. Data are compared with radiation damage simulations, based on detailed maps of the electric field in the Si substrate, at various fluence levels and bias voltage values. These results illustrate the potential of 3D technology for pixel applications in high-radiation environments.

Tree growth and longevity trade-offs fundamentally shape the terrestrial carbon balance. Yet, we lack a unified understanding of how such trade-offs vary across the world's forests. By mapping life history traits for a wide range of species across the Americas, we reveal considerable variation in life expectancies from 10 centimeters in diameter (ranging from 1.3 to 3195 years) and show that the pace of life for trees can be accurately classified into four demographic functional types. We found emergent patterns in the strength of trade-offs between growth and longevity across a temperature gradient. Furthermore, we show that the diversity of life history traits varies predictably across forest biomes, giving rise to a positive relationship between trait diversity and productivity. Our pan-latitudinal assessment provides new insights into the demographic mechanisms that govern the carbon turnover rate across forest biomes.

Results from a wide range of searches targeting different experimental signatures with and without missing transverse momentum (ETmiss) are used to constrain a Two-Higgs-Doublet Model (2HDM) with an additional pseudo-scalar mediating the interaction between ordinary and dark matter (2HDM+a). The analyses use up to 139 fb-1 of proton-proton collision data at a centre-of-mass energy s=13 TeV recorded with the ATLAS detector at the Large Hadron Collider during 2015-2018. The results from three of the most sensitive searches are combined statistically. These searches target signatures with large ETmiss and a leptonically decaying Z boson; large ETmiss and a Higgs boson decaying to bottom quarks; and production of charged Higgs bosons in final states with top and bottom quarks, respectively. Constraints are derived for several common and new benchmark scenarios in the 2HDM+a.