| 1. |
- Thomas, HS, et al.
(författare)
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- 2019
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swepub:Mat__t
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| 2. |
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| 3. |
- Bravo, L, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 4. |
- Drake, TM, et al.
(författare)
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Surgical site infection after gastrointestinal surgery in children: an international, multicentre, prospective cohort study
- 2020
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Ingår i: BMJ global health. - : BMJ. - 2059-7908. ; 5:12
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Tidskriftsartikel (refereegranskat)abstract
- Surgical site infection (SSI) is one of the most common healthcare-associated infections (HAIs). However, there is a lack of data available about SSI in children worldwide, especially from low-income and middle-income countries. This study aimed to estimate the incidence of SSI in children and associations between SSI and morbidity across human development settings.MethodsA multicentre, international, prospective, validated cohort study of children aged under 16 years undergoing clean-contaminated, contaminated or dirty gastrointestinal surgery. Any hospital in the world providing paediatric surgery was eligible to contribute data between January and July 2016. The primary outcome was the incidence of SSI by 30 days. Relationships between explanatory variables and SSI were examined using multilevel logistic regression. Countries were stratified into high development, middle development and low development groups using the United Nations Human Development Index (HDI).ResultsOf 1159 children across 181 hospitals in 51 countries, 523 (45·1%) children were from high HDI, 397 (34·2%) from middle HDI and 239 (20·6%) from low HDI countries. The 30-day SSI rate was 6.3% (33/523) in high HDI, 12·8% (51/397) in middle HDI and 24·7% (59/239) in low HDI countries. SSI was associated with higher incidence of 30-day mortality, intervention, organ-space infection and other HAIs, with the highest rates seen in low HDI countries. Median length of stay in patients who had an SSI was longer (7.0 days), compared with 3.0 days in patients who did not have an SSI. Use of laparoscopy was associated with significantly lower SSI rates, even after accounting for HDI.ConclusionThe odds of SSI in children is nearly four times greater in low HDI compared with high HDI countries. Policies to reduce SSI should be prioritised as part of the wider global agenda.
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| 5. |
- Tabiri, S, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 6. |
- Kanai, M, et al.
(författare)
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- 2023
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swepub:Mat__t
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| 7. |
- Khatri, C, et al.
(författare)
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Outcomes after perioperative SARS-CoV-2 infection in patients with proximal femoral fractures: an international cohort study
- 2021
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Ingår i: BMJ open. - : BMJ. - 2044-6055. ; 11:11, s. e050830-
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Tidskriftsartikel (refereegranskat)abstract
- Studies have demonstrated high rates of mortality in people with proximal femoral fracture and SARS-CoV-2, but there is limited published data on the factors that influence mortality for clinicians to make informed treatment decisions. This study aims to report the 30-day mortality associated with perioperative infection of patients undergoing surgery for proximal femoral fractures and to examine the factors that influence mortality in a multivariate analysis.SettingProspective, international, multicentre, observational cohort study.ParticipantsPatients undergoing any operation for a proximal femoral fracture from 1 February to 30 April 2020 and with perioperative SARS-CoV-2 infection (either 7 days prior or 30-day postoperative).Primary outcome30-day mortality. Multivariate modelling was performed to identify factors associated with 30-day mortality.ResultsThis study reports included 1063 patients from 174 hospitals in 19 countries. Overall 30-day mortality was 29.4% (313/1063). In an adjusted model, 30-day mortality was associated with male gender (OR 2.29, 95% CI 1.68 to 3.13, p<0.001), age >80 years (OR 1.60, 95% CI 1.1 to 2.31, p=0.013), preoperative diagnosis of dementia (OR 1.57, 95% CI 1.15 to 2.16, p=0.005), kidney disease (OR 1.73, 95% CI 1.18 to 2.55, p=0.005) and congestive heart failure (OR 1.62, 95% CI 1.06 to 2.48, p=0.025). Mortality at 30 days was lower in patients with a preoperative diagnosis of SARS-CoV-2 (OR 0.6, 95% CI 0.6 (0.42 to 0.85), p=0.004). There was no difference in mortality in patients with an increase to delay in surgery (p=0.220) or type of anaesthetic given (p=0.787).ConclusionsPatients undergoing surgery for a proximal femoral fracture with a perioperative infection of SARS-CoV-2 have a high rate of mortality. This study would support the need for providing these patients with individualised medical and anaesthetic care, including medical optimisation before theatre. Careful preoperative counselling is needed for those with a proximal femoral fracture and SARS-CoV-2, especially those in the highest risk groups.Trial registration numberNCT04323644
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| 8. |
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| 9. |
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| 10. |
- Niemi, MEK, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 11. |
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| 12. |
- Abdo, A. A., et al.
(författare)
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DETECTION OF GAMMA-RAY EMISSION FROM THE STARBURST GALAXIES M82 AND NGC 253 WITH THE LARGE AREA TELESCOPE ON FERMI
- 2010
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Ingår i: The Astrophysical Journal Letters. - 2041-8205 .- 2041-8213. ; 709:2, s. l152-L157
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Tidskriftsartikel (refereegranskat)abstract
- We report the detection of high-energy gamma-ray emission from two starburst galaxies using data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. Steady point-like emission above 200 MeV has been detected at significance levels of 6.8 sigma and 4.8 sigma, respectively, from sources positionally coincident with locations of the starburst galaxies M82 and NGC 253. The total fluxes of the sources are consistent with gamma-ray emission originating from the interaction of cosmic rays with local interstellar gas and radiation fields and constitute evidence for a link between massive star formation and gamma-ray emission in star-forming galaxies.
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| 13. |
- Abdo, A. A., et al.
(författare)
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SPECTRAL PROPERTIES OF BRIGHT FERMI-DETECTED BLAZARS IN THE GAMMA-RAY BAND
- 2010
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 710:2, s. 1271-1285
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Tidskriftsartikel (refereegranskat)abstract
- The gamma-ray energy spectra of bright blazars of the LAT Bright AGN Sample LBAS) are investigated using Fermi-LAT data. Spectral properties hardness, curvature, and variability) established using a data set accumulated over 6 months of operation are presented and discussed for different blazar classes and subclasses: flat spectrum radio quasars (FSRQs), low-synchrotron peaked BLLacs (LSP-BLLacs), intermediate-synchrotron peaked BLLacs (ISP-BLLacs), and high-synchrotron peaked BLLacs (HSP-BLLacs). The distribution of photon index G, obtained from a power-law fit above 100 MeV) is found to correlate strongly with blazar subclass. The change in spectral index from that averaged over the 6 months observing period is < 0.2-0.3 when the flux varies by about an order of magnitude, with a tendency toward harder spectra when the flux is brighter for FSRQs and LSP-BLLacs. A strong departure from a single power-law spectrum appears to be a common feature for FSRQs. This feature is also present for some high-luminosity LSP-BLLacs, and a small number of ISP-BLLacs. It is absent in all LBAS HSP-BLLacs. For 3C 454.3 and AO 0235+164, the two brightest FSRQ source and LSP-BLLac source, respectively, a broken power law (BPL) gives the most acceptable of power law, BPL, and curved forms. The consequences of these findings are discussed.
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| 14. |
- Abdo, A. A., et al.
(författare)
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THE FIRST FERMI MULTIFREQUENCY CAMPAIGN ON BL LACERTAE : CHARACTERIZING THE LOW-ACTIVITY STATE OF THE EPONYMOUS BLAZAR
- 2011
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 730:2, s. 101-
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Tidskriftsartikel (refereegranskat)abstract
- We report on observations of BL Lacertae during the first 18 months of Fermi LAT science operations and present results from a 48 day multifrequency coordinated campaign from 2008 August 19 to 2008 October 7. The radio to gamma-ray behavior of BL Lac is unveiled during a low-activity state thanks to the coordinated observations of radio-band (Metsahovi and VLBA), near-IR/optical (Tuorla, Steward, OAGH, and MDM), and X-ray (RXTE and Swift) observatories. No variability was resolved in gamma rays during the campaign, and the brightness level was 15 times lower than the level of the 1997 EGRET outburst. Moderate and uncorrelated variability has been detected in UV and X-rays. The X-ray spectrum is found to be concave, indicating the transition region between the low- and high-energy components of the spectral energy distribution (SED). VLBA observation detected a synchrotron spectrum self-absorption turnover in the innermost part of the radio jet appearing to be elongated and inhomogeneous, and constrained the average magnetic field there to be less than 3 G. Over the following months, BL Lac appeared variable in gamma rays, showing flares (in 2009 April and 2010 January). There is no evidence for the correlation of gamma rays with the optical flux monitored from the ground in 18 months. The SED may be described by a single-zone or a two-zone synchrotron self-Compton (SSC) model, but a hybrid SSC plus external radiation Compton model seems to be preferred based on the observed variability and the fact that it provides a fit closest to equipartition.
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| 15. |
- Aricescu, A R, et al.
(författare)
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Eukaryotic expression: developments for structural proteomics.
- 2006
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Ingår i: Acta Crystallographica Section D: Biological Crystallography. - 1399-0047 .- 0907-4449. ; 62, s. 1114-1124
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Tidskriftsartikel (refereegranskat)abstract
- The production of sufficient quantities of protein is an essential prelude to a structure determination, but for many viral and human proteins this cannot be achieved using prokaryotic expression systems. Groups in the Structural Proteomics In Europe (SPINE) consortium have developed and implemented high-throughput (HTP) methodologies for cloning, expression screening and protein production in eukaryotic systems. Studies focused on three systems: yeast (Pichia pastoris and Saccharomyces cerevisiae), baculovirus-infected insect cells and transient expression in mammalian cells. Suitable vectors for HTP cloning are described and results from their use in expression screening and protein-production pipelines are reported. Strategies for co-expression, selenomethionine labelling (in all three eukaryotic systems) and control of glycosylation (for secreted proteins in mammalian cells) are assessed.
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| 16. |
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| 17. |
- Boyd, Philip, et al.
(författare)
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Handbook to support the SCOR Best Practice Guide for ‘Multiple Drivers’ Marine Research
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Marine species and ecosystems are exposed to a wide range of environmental change – both detrimental (threats) and beneficial – due to human activities. Some of the changes are global, whereas others are regional or local. It is important to distinguish the scale of each threat as the solutions will differ. For example, the mitigation of a global problem requires a global response, which is more difficult to achieve than addressing a local problem with a local response. These wide-ranging changes are often referred to drivers or stressors.
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| 18. |
- Hofsten, von, Claes, et al.
(författare)
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Improved visual perception in very low birth weight infants on enhanced nutrient supply
- 2015
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Ingår i: Neonatalogy. - : S. Karger. - 1661-7800. ; 108, s. 30-37
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Tidskriftsartikel (refereegranskat)abstract
- <b><i>Background:</i></b> Optimal nutrient supply to very low birth weight (VLBW: BW <1,500 g) infants is important for growth and neurodevelopment. Growth restriction is common among these infants and may be associated with neurocognitive impairments. <b><i>Objectives:</i></b> To compare an enhanced nutrient supply to a routine supply given to VLBW infants and to evaluate the effects on visual perception of global form and motion measured by visual event-related potentials (VERP). <b><i>Methods:</i></b> A total of 50 VLBW infants were randomized to an intervention group that received an increased supply of energy, protein, fat, essential fatty acids, and vitamin A or a control group that received standard nutritional care. At 5 months' corrected age the infants were examined using VERP to investigate the responses to global form and motion. VERP were analysed at the first (f1) and third (f3) harmonics of the stimulus frequency. <b><i>Results:</i></b> Data from 31 subjects were eligible for analysis. The motion VERP responses for the f1 and f3 components were stronger in the area near the posterior midline region in the intervention group compared to the controls in the group analyses (p = 0.02 and p = 0.001, respectively). <b><i>Conclusion:</i></b> The results showed a more consistent response to global motion among infants receiving enhanced nutrition. The intervention may have improved visual perception of global motion.
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| 19. |
- Kenward, R. E., et al.
(författare)
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Identifying governance strategies that effectively support ecosystem services, resource sustainability, and biodiversity
- 2011
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 108:13, s. 5308-5312
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Tidskriftsartikel (refereegranskat)abstract
- Conservation scientists, national governments, and international conservation groups seek to devise, and implement, governance strategies that mitigate human impact on the environment. However, few studies to date have systematically investigated the performance of different systems of governance in achieving successful conservation outcomes. Here, we use a newly-developed analytic framework to conduct analyses of a suite of case studies, linking different governance strategies to standardized scores for delivering ecosystem services, achieving sustainable use of natural resources, and conserving biodiversity, at both local and international levels. Our results: (i) confirm the benefits of adaptive management; and (ii) reveal strong associations for the role of leadership. Our work provides a critical step toward implementing empirically justified governance strategies that are capable of improving the management of human-altered environments, with benefits for both biodiversity and people.
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| 20. |
- Lee, Sang-Han, et al.
(författare)
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Distribution of plutonium and americium in the marginal seas of the nothwest pacific ocean.
- 2003
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Ingår i: Deep-sea research. Part II, Topical studies in oceanography. - 0967-0645 .- 1879-0100. ; 50, s. 2727-2750
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Tidskriftsartikel (refereegranskat)abstract
- Plutonium isotopes and 241Am were studied in seawater and sediment from the East China Sea, the Yellow Sea, the East Sea/Sea of Japan, the Sea of Okhotsk, and the northwest Pacific Ocean, collected between 1993 and 1996 with the aim to contribute to better understanding the behaviour of plutonium and americium in the marine environment. 239,240Pu concentrations in surface water varied from 2.3 to 13 µBq l-1 in the East China Sea and from 3.5 to 9.4 µBq l-1 in the East Sea. The 239,240Pu vertical profiles in water showed a broad subsurface maximum between 500 and 1000 m with a range of 30-40 µBq l-1, and gradually decreased from 1000 m depth down to the seafloor. 241Am concentrations in surface water showed values from 1.1 to 2.2 µBq l -1 in the East Sea, from 1.0 to 3.1 µBq l-1 in the Sea of Okhotsk, and from 0.68 to 12.0 µBq l-1 in the northwest Pacific Ocean. The activity ratios of 241Am/239,240Pu in seawater showed values similar to the global fallout ratio, which suggests that the source of these radionuclides in the northwest Pacific Ocean is global fallout. However, the 241Am/239,240Pu activity ratios in sediment were found to be much higher (1.0-1.9) than the global fallout ratio (0.37), confirming that 241Am is scavenged from the water column more rapidly than 239,240Pu. The 239,240Pu inventories in the water column of the East Sea were from 0.98 to 93 Bq m-2 depending on water depth and sedimentation rates. The 241Am inventory in the water column east of Kamchatka was 6.3 ± 1.0 Bq m -2 and the sediment inventory in the Sea of Okhotsk was 16 ± 2 Bq m-2. 239,240Pu concentrations in sinking particles in the southwest Japan Basin were from 3.7 to 5.2 Bq kg-1 (dry weight) with fluxes of 0.19-4.50 mBq m-2 d-1 and at the Ulleung Basin from 2.4 to 3.7 Bq kg-1 (dry weight) with fluxes of 0.77-1.10 mBq m-2 d-1. The mean residence time of 239,240Pu in the water column of the East Sea derived from sediment trap data was 140 ± 20 years, 2-3 times less than in the Atlantic and Pacific oceans.
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| 21. |
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| 22. |
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| 23. |
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| 24. |
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| 25. |
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| 26. |
- Hellsing, AL, et al.
(författare)
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Ergonomic education for nursing students
- 1993
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Ingår i: International Journal of Nursing Studies. - 0020-7489 .- 1873-491X. ; 30:6, s. 499-510
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Tidskriftsartikel (refereegranskat)
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| 27. |
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| 28. |
- Pascual, Unai, et al.
(författare)
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Valuing nature's contributions to people : the IPBES approach
- 2017
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Ingår i: Current Opinion in Environmental Sustainability. - : Elsevier BV. - 1877-3435. ; 26-27, s. 7-16
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Forskningsöversikt (refereegranskat)abstract
- Nature is perceived and valued in starkly different and often conflicting ways. This paper presents the rationale for the inclusive valuation of nature's contributions to people (NCP) in decision making, as well as broad methodological steps for doing so. While developed within the context of the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), this approach is more widely applicable to initiatives at the knowledge–policy interface, which require a pluralistic approach to recognizing the diversity of values. We argue that transformative practices aiming at sustainable futures would benefit from embracing such diversity, which require recognizing and addressing power relationships across stakeholder groups that hold different values on human nature-relations and NCP.
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| 29. |
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| 30. |
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| 31. |
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| 32. |
- Aad, Georges, et al.
(författare)
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Jet energy measurement with the ATLAS detector in proton- proton collisions at sqrt(s) = 7 TeV
- 2011
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The jet energy scale (JES) and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of sqrt(s) = 7 TeV corresponding to an integrated luminosity of 38 inverse pb. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0.4 or R=0.6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pt > 20 GeV and pseudorapidities eta<4.5. The JES systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams. The JES uncertainty is less than 2.5% in the central calorimeter region (eta<0.8) for jets with 60 < pt < 800 GeV, and is maximally 14% for pt < 30 GeV in the most forward region 3.2 50 GeV after a dedicated correction for this effect. The JES is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pt, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pt jets recoiling against a high-pt jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, providing an improved jet energy resolution and a reduced flavour dependence of the jet response. The JES systematic uncertainty determined from a combination of in situ techniques are consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pt jets.
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| 33. |
- Aad, Georges, et al.
(författare)
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Measurement of inclusive jet and dijet production in pp collisions at sqrt(s) = 7 TeV using the ATLAS detector
- 2011
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Ingår i: Physical Review D. - 1550-7998 .- 1550-2368.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Inclusive jet and dijet cross sections have been measured in proton-proton collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector at the Large Hadron Collider. The cross sections were measured using jets clustered with the anti-kT algorithm with parameters R=0.4 and R=0.6. These measurements are based on the 2010 data sample, consisting of a total integrated luminosity of 37 inverse picobarns. Inclusive jet double-differential cross sections are presented as a function of jet transverse momentum, in bins of jet rapidity. Dijet double-differential cross sections are studied as a function of the dijet invariant mass, in bins of half the rapidity separation of the two leading jets. The measurements are performed in the jet rapidity range |y|<4.4, covering jet transverse momenta from 20 GeV to 1.5 TeV and dijet invariant masses from 70 GeV to 5 TeV. The data are compared to expectations based on next-to-leading order QCD calculations corrected for non-perturbative effects, as well as to next-to-leading order Monte Carlo predictions. In addition to a test of the theory in a new kinematic regime, the data also provide sensitivity to parton distribution functions in a region where they are currently not well-constrained.
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| 34. |
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| 35. |
- Aad, Georges, et al.
(författare)
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Measurement of the inclusive W+- and Z/gamma cross sections in the electron and muon decay channels in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
- 2011
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The production cross sections of the inclusive Drell-Yan processes W to l nu and Z/gamma to ll (l=e,mu) are measured in proton-proton collisions at sqrt(s) = 7 TeV with the ATLAS detector. The cross sections are reported integrated over a fiducial kinematic range, extrapolated to the full range and also evaluated differentially as a function of the W decay lepton pseudorapidity and the Z boson rapidity, respectively. Based on an integrated luminosity of about 35 pb^-1 collected in 2010, the precision of these measurements reaches a few per cent. The integrated and the differential W+- and Z/gamma cross sections in the e and mu channels are combined, and compared with perturbative QCD calculations, based on a number of different parton distribution sets available at NNLO.
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| 36. |
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| 37. |
- Aad, Georges, et al.
(författare)
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Measurement of the WW cross section in sqrt(s) = 7 TeV pp collisions with ATLAS
- 2011
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 107
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- This Letter presents a measurement of the W+W− production cross section in s√ = 7 TeV pp collisions by the ATLAS experiment, using 34 pb−1 of integrated luminosity produced by the Large Hadron Collider at CERN. Selecting events with two isolated leptons, each either an electron or a muon, 8 candidate events are observed with an expected background of 1.7±0.6 events. The measured cross section is 41+20−16(stat)±5(syst)±1(lumi) pb, which is consistent with the standard model prediction of 44±3 pb calculated at next-to-leading order in QCD.
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| 38. |
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| 39. |
- Aad, G., et al.
(författare)
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Search for long-lived charginos based on a disappearing-track signature using 136 fb−1 of pp collisions at √s = 13 TeV with the ATLAS detector
- 2022
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 82:7
-
Tidskriftsartikel (refereegranskat)abstract
- A search for long-lived charginos produced either directly or in the cascade decay of heavy prompt gluino states is presented. The search is based on proton–proton collision data collected at a centre-of-mass energy of s√s = 13 TeVeV between 2015 and 2018 with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 136 fb−1. Long-lived charginos are characterised by a distinct signature of a short and then disappearing track, and are reconstructed using at least four measurements in the ATLAS pixel detector, with no subsequent measurements in the silicon-microstrip tracking volume nor any associated energy deposits in the calorimeter. The final state is complemented by a large missing transverse-momentum requirement for triggering purposes and at least one high-transverse-momentum jet. No excess above the expected backgrounds is observed. Exclusion limits are set at 95% confidence level on the masses of the chargino and gluino for different chargino lifetimes. Chargino masses up to 660 (210) GeVeV are excluded in scenarios where the chargino is a pure wino (higgsino). For charginos produced during the cascade decay of a heavy gluino, gluinos with masses below 2.1 TeVeV are excluded for a chargino mass of 300 GeVeV and a lifetime of 0.2 ns.
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| 40. |
- Aad, G., et al.
(författare)
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Search for non-resonant Higgs boson pair production in the 2b+2ℓ+ETmiss final state in pp collisions at s = 13 TeV with the ATLAS detector
- 2024
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Ingår i: Journal of High Energy Physics. - : Springer Science and Business Media Deutschland GmbH. - 1029-8479 .- 1126-6708. ; 2024:2
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Tidskriftsartikel (refereegranskat)abstract
- A search for non-resonant Higgs boson pair (HH) production is presented, in which one of the Higgs bosons decays to a b-quark pair (bb¯) and the other decays to WW*, ZZ*, or τ+τ−, with in each case a final state with ℓ+ℓ−+ neutrinos (ℓ = e, μ). The analysis targets separately the gluon-gluon fusion and vector boson fusion production modes. Data recorded by the ATLAS detector in proton-proton collisions at a centre-of-mass energy of 13 TeV at the Large Hadron Collider, corresponding to an integrated luminosity of 140 fb−1, are used in this analysis. Events are selected to have exactly two b-tagged jets and two leptons with opposite electric charge and missing transverse momentum in the final state. These events are classified using multivariate analysis algorithms to separate the HH events from other Standard Model processes. No evidence of the signal is found. The observed (expected) upper limit on the cross-section for non-resonant Higgs boson pair production is determined to be 9.7 (16.2) times the Standard Model prediction at 95% confidence level. The Higgs boson self-interaction coupling parameter κλ and the quadrilinear coupling parameter κ2V are each separately constrained by this analysis to be within the ranges [−6.2, 13.3] and [−0.17, 2.4], respectively, at 95% confidence level, when all other parameters are fixed. © The Author(s) 2024.
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| 41. |
- Aad, Georges, et al.
(författare)
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Search for production of resonant states in the photon-jet mass distribution using pp collisions at sqrt(s) = 7 TeV collected by the ATLAS detector
- 2011
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- This Letter describes a model-independent search for production of new resonant states in photon-jet events in 2.11 fb^-1 of proton-proton collisions at sqrt(s) = 7 TeV. We compare the photon-jet mass distribution to a data-driven background estimate and find consistency with the background hypothesis. Given the lack of evidence for a signal, we set 95% CL limits on generic Gaussian-shape signals and on a benchmark excited-quark (q*) model, excluding 2 TeV Gaussian resonances with cross section times branching ratio times acceptance times efficiency near 5 fb and excluding q* masses below 2.46 TeV, respectively.
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| 42. |
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| 43. |
- Aad, G., et al.
(författare)
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The ATLAS Experiment at the CERN Large Hadron Collider
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3:S08003
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Forskningsöversikt (refereegranskat)abstract
- The ATLAS detector as installed in its experimental cavern at point 1 at CERN is described in this paper. A brief overview of the expected performance of the detector when the Large Hadron Collider begins operation is also presented.
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| 44. |
- Aad, G., et al.
(författare)
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Two-particle Bose–Einstein correlations in pp collisions at s√=13s=13 TeV measured with the ATLAS detector at the LHC
- 2022
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 82:7
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents studies of Bose–Einstein correlations (BEC) in proton–proton collisions at a centre-of-mass energy of 13 TeV, using data from the ATLAS detector at the CERN Large Hadron Collider. Data were collected in a special low-luminosity configuration with a minimum-bias trigger and a high-multiplicity track trigger, accumulating integrated luminosities of 151 μμb−1 and 8.4 nb−1, respectively. The BEC are measured for pairs of like-sign charged particles, each with |η|<2.5|η|<2.5, for two kinematic ranges: the first with particle pT>100 MeV and the second with particle pT>500 MeV. The BEC parameters, characterizing the source radius and particle correlation strength, are investigated as functions of charged-particle multiplicity (up to 300) and average transverse momentum of the pair (up to 1.5 GeV). The double-differential dependence on charged-particle multiplicity and average transverse momentum of the pair is also studied. The BEC radius is found to be independent of the charged-particle multiplicity for high charged-particle multiplicity (above 100), confirming a previous observation at lower energy. This saturation occurs independent of the transverse momentum of the pair.
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| 45. |
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| 46. |
- Abat, E., et al.
(författare)
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Photon reconstruction in the ATLAS Inner Detector and Liquid Argon Barrel Calorimeter at the 2004 Combined Test Beam
- 2011
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- The reconstruction of photons in the ATLAS detector is studied with data taken during the 2004 Combined Test Beam, where a full slice of the ATLAS detector was exposed to beams of particles of known energy at the CERN SPS. The results presented show significant differences in the longitudinal development of the electromagnetic shower between converted and unconverted photons as well as in the total measured energy. The potential to use the reconstructed converted photons as a means to precisely map the material of the tracker in front of the electromagnetic calorimeter is also considered. All results obtained are compared with a detailed Monte-Carlo simulation of the test-beam setup which is based on the same simulation and reconstruction tools as those used for the ATLAS detector itself.
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| 47. |
- Abat, E., et al.
(författare)
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Study of the response of the ATLAS central calorimeter to pions of energies from 3 to 9 GeV
- 2009
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002 .- 1872-9576. ; 607:2, s. 372-386
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Tidskriftsartikel (refereegranskat)abstract
- A fully instrumented slice of the ATLAS central detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. in this paper, the response of the central calorimeters to pions with energies in the range between 3 and 9 GeV is presented. The linearity and the resolution of the combined calorimetry (electromagnetic and hadronic calorimeters) was measured and compared to the prediction of a detector simulation program using the toolkit Geant 4. (C) 2009 Elsevier B.V. All rights reserved.
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| 48. |
- Abazov, V. M., et al.
(författare)
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Combined measurements of anomalous charged trilinear gauge-boson couplings from diboson production in p-pbar collisions at sqrt(s)=1.96 TeV
- 2009
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Ingår i: Physics Letters B. - 0370-2693 .- 1873-2445.
-
Tidskriftsartikel (refereegranskat)abstract
- We present measurements of the anomalous WWgamma and WWZ trilinear gauge couplings from a combination of four diboson production and decay channels using data collected by the D0 detector at the Fermilab Tevatron Collider. These results represent the first high statistics combination of limits across different diboson production processes at the Tevatron and use data corresponding to an integrated luminosity of approximately 1 fb^-1. When respecting SU(2)_L x U(1)_Y symmetry, we measure central values and 68% C.L. allowed intervals of kappa_gamma=1.07^+0.16_-0.20, lambda =0.00^+0.05_-0.04 and g_1^Z=1.05 +/- 0.06. We present the most stringent measurements to date for the W boson magnetic dipole and electromagnetic quadrupole moments of mu_W=2.02^+0.08_-0.09 (e/2M_W) and q_W=-1.00 +/- 0.09 (e/M^2_W), respectively.
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| 49. |
- Abazov, V. M., et al.
(författare)
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Search for supersymmetry with gauge-mediated breaking in diphoton events at DØ
- 2005
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 94:4
-
Tidskriftsartikel (refereegranskat)abstract
- We report the results of a search for supersymmetry (SUSY) with gauge-mediatedbreaking in the missing transverse energy distribution of inclusive diphoton events using 263 pb -1 of data collected by the DO experiment at the Fermilab Tevatron Collider in 2002-2004. No excess is observed above the background expected from standard model processes, and lower limits on the masses of the lightest neutralino and chargino of about 108 and 195 GeV, respectively, are set at the 95% confidence level. These are the most stringent limits to date for models with gauge-mediated SUSY breaking with a short-lived neutralino as the next-to-lightest SUSY particle.
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| 50. |
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