1,306 research outputs found
Resonant leptoquark at NLO with POWHEG
Get PDFAbstract Recent progress in calculating lepton density functions inside the proton and simulating lepton showers laid the foundations for precision studies of resonant leptoquark production at hadron colliders. Direct quark-lepton fusion into a leptoquark is a novel production channel at the LHC that has the potential to probe a unique parameter space for large masses and couplings. In this work, we build the first Monte Carlo event generator for a full-fledged simulation of this process at NLO for production, followed by a subsequent decay using the POWHEG method and matching to the parton showers utilizing HERWIG. The code can handle all scalar leptoquark models with renormalisable quark-lepton interactions. We then comprehensively study the differential distributions, including higher-order effects, and assess the corresponding theoretical uncertainties. We also quantify the impact of the improved predictions on the projected (HL-)LHC sensitivities and initiate the first exploration of the potential at the FCC-hh. Our work paves the way toward performing LHC searches using this channel
Giulia Veronica Varisco
No full textThe headword explains the biography and the contribution of the author Giulia Varisco to the children's literatur
QCDLoop: a comprehensive framework for one-loop scalar integrals
Get PDFWe present a new release of the QCDLoop library based on a modern object-oriented framework. We discuss the available new features such as the extension to the complex masses, the possibility to perform computations in double and quadruple precision simultaneously, and useful caching mechanisms to improve the computational speed. We benchmark the performance of the new library, and provide practical examples of phenomenological implementations by interfacing this new library to Monte Carlo programs.We present a new release of the QCDLoop library based on a modern object-oriented framework. We discuss the available new features such as the extension to the complex masses, the possibility to perform computations in double and quadruple precision simultaneously, and useful caching mechanisms to improve the computational speed. We benchmark the performance of the new library, and provide practical examples of phenomenological implementations by interfacing this new library to Monte Carlo programs
Next-to-leading order QCD predictions for W(+)W(+)jj production at the LHC
Get PDFBecause the LHC is a proton-proton collider, sizable production of two positively charged W-bosons in association with two jets is possible. This process leads to a distinct signature of same sign high-p(perpendicular to) leptons, missing energy and jets. We compute the NLO QCD corrections to the QCD-mediated part of pp -> W(+)W(+)jj. These corrections reduce the dependence of the production cross-section on the renormalization and factorization scale to about +/- 10 percent. We find that a large number of W(+)W(+)jj events contain a relatively hard third jet. The presence of this jet should help to either pick up the W(+)W(+)jj signal or to reject it as an unwanted background
MINLO t-channel single-top plus jet
Get PDFWe present a next-to-leading order accurate simulation of t-channel single-top plus jet production matched to parton showers via the Powheg method. The calculation underlying the simulation is enhanced with a process-specific implementation of the multi-scale improved NLO (Minlo) method, such that it gives physical predictions all through phase space, including regions where the jet additional to the t-channel single-top process is unresolved. We further describe a tuning procedure for the Minlo Sudakov form factor, fitting the coefficient of the first subleading term in its exponent using an artificial neural-network. The latter tuning, implemented as a straightforward event-by-event reweighting, renders the Minlo simulation NLO accurate for t-channel single-top observables, in addition to those of the analogous single-top plus jet process.We present a next-to-leading order accurate simulation of t-channel single-top plus jet production matched to parton showers via the POWHEG method. The calculation underlying the simulation is enhanced with a process-specific implementation of the multi-scale improved NLO (MINLO) method, such that it gives physical predictions all through phase space, including regions where the jet additional to the t-channel single-top process is unresolved. We further describe a tuning procedure for the MINLO Sudakov form factor, fitting the coefficient of the first subleading term in its exponent using an artificial neural-network. The latter tuning, implemented as a straightforward event-by-event reweighting, renders the MINLO simulation NLO accurate for t-channel single-top observables, in addition to those of the analogous single-top plus jet process
Accurate predictions for heavy quark jets
No full textHeavy-flavour jets enter many of today's collider studies, yet NLO predictions for these quantities are subject to large uncertainties, larger than the corresponding experimental errors. We propose a new, infrared safe definition of heavy-quark jets which allows one to reduce theoretical uncertainties by a factor of three
Ytterbium Disilicate/Monosilicate Multilayer Environmental Barrier Coatings: Influence of Atmospheric Plasma Spray Parameters on Composition and Microstructure
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Open AccessArticle
Ytterbium Disilicate/Monosilicate Multilayer Environmental Barrier Coatings: Influence of Atmospheric Plasma Spray Parameters on Composition and Microstructure
by Giulia Di Iorio,Laura Paglia *ORCID,Giulia PedrizzettiORCID,Virgilio GenovaORCID,Francesco MarraORCID,Cecilia BartuliORCID andGiovanni PulciORCID
INSTM Reference Laboratory for Materials and Surface Engineering, Sapienza University of Rome, Eudossiana 18, 00184 Rome, Italy
*
Author to whom correspondence should be addressed.
Coatings 2023, 13(9), 1602; https://doi.org/10.3390/coatings13091602
Original submission received: 10 August 2023 / Revised: 31 August 2023 / Accepted: 11 September 2023 / Published: 13 September 2023
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Abstract
SiC/SiC ceramic matrix composites (SiCf/SiC CMCs) are regarded as the new materials for the hot-section components of aircraft gas turbine engines, since they have one-third of the density of metallic superalloys, a higher temperature capability, good mechanical strength, and excellent thermal shock resistance. However, high-temperature water-vapor-rich combustion gases can induce severe surface recession phenomena in SiC/SiC leading to component failure. For this reason, it is necessary to design protective coatings, i.e., environmental barrier coatings (EBCs), able to protect the SiC/SiC surface in combustion environments. In the present work, ytterbium monosilicate (Yb2SiO5), stable when exposed to water vapor at high temperatures, and ytterbium disilicate (Yb2Si2O7), characterized by a thermal expansion coefficient closer to that of the substrate, were selected for a multilayer EBC system. EBCs were processed using the atmospheric plasma spray (APS) technique. A set of deposition parameters were tested, varying the power of the torch, and the composition and microstructure of the deposited coatings were studied in terms of porosity, crack density, and post-deposition phase retention by performing SEM, EDS, and XRD analysis. The results allow for the definition of the influence of deposition parameters on the final properties of multilayer EBC coatings
Gauge boson production at colliders - Predictions for precision studies
No full textThe status of today's theoretical description of Standard Model (SM) processes involving gauge bosons at the Tevatron and the LHC, and of the tools that are used in their phenomenological studies are reviewed. A few recent ideas to further improve on the way technically challenging calculations can be performed also are discussed. © Indian Academy of Sciences
Correction to: Safety and Psychological Outcomes of Tandem t:Slim X2 Insulin Pump with Control-IQ Technology in Children, Adolescents, and Young Adults with Type 1 Diabetes: A Systematic Review
Get PDFThe second author name was incorrectly published as Giula Maria Smylie. The correct name is Giulia Marie Smylie. The original article has been corrected
Out-of-plane QCD radiation in dis events with high P-T jets
No full textWe present the QCD analysis of the out-of-event-plane momentum distribution in DIS events with high p(t) jets. The achieved accuracy allows the measurement of the running coupling and the study of non-perturbative effects, in particular the test of universality of power corrections in a new experimental regime
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