Single Cross Sections Research Articles

The signatures of doubly charged leptons at LHeC

In this paper, we study the production of the doubly charged leptons at the future ep collider large hadron electron collider (LHeC). Such states are introduced in extended weak isospin multiplets by composite models. We calculate the single production cross sections of the doubly charged leptons, and carry out a fast simulation for the signals and the corresponding backgrounds. We plot the 3σ and 5σ statistical significance exclusion curves in the parameter space (Λ, ML) and (). Our analysis shows that the possible signatures of the doubly charged leptons might be detected in the future LHeC, the leptonic channel has advantage in detecting the doubly charged lepton signals compared to the hadronic channel.

Fusing vectors into scalars at high energy lepton colliders

We study vector boson fusion production of new scalar singlets at high energy lepton colliders. We find that CLIC has the potential to test single production cross-sections of a few tens of attobarns in di-Higgs and di-boson final states. In models with a sizeable singlet-Higgs mixing, these values correspond to a precision in Higgs couplings of order 0.1% or better. We compare our sensitivities with those of the LHC and interpret our results in well-motivated models like the Twin Higgs, the NMSSM and axion-like particles. Looking forward to even higher energy machines, we show that the reach of muon colliders like LEMMA or MAP overcomes the one of future hadron machines like FCC-hh. We finally study the pair production of the new scalar singlets via an off-shell Higgs. This process does not vanish for small mixings and will constitute a crucial probe of models generating a first order electro-weak phase transition.

GEANT4 simulation of nuclear interaction induced soft errors in digital nanoscale electronics: Interrelation between proton and heavy ion impacts

A simple and self-consistent approach has been proposed for simulation of the proton-induced soft error rate based on the heavy ion induced single event upset cross-section data and vice versa. The approach relies on the GEANT4 assisted Monte Carlo simulation of the secondary particle LET spectra produced by nuclear interactions. The method has been validated with the relevant in-flight soft error rate data for space protons and heavy ions. An approximate analytical relation is proposed and validated for a fast recalculation between two types of experimental data.

Infrared sensitivity of single jet inclusive production at hadron colliders

Jet production at hadron colliders is a benchmark process to probe the dynamics of the strong interaction and the structure of the colliding hadrons. One of the most basic jet production observables is the single jet inclusive cross section, which is obtained by summing all jets that are observed in an event. Our recent computation of next-to-next-to-leading order (NNLO) QCD contributions to single jet inclusive observables uncovered large corrections in certain kinematical regions, which also resulted in a sizeable ambiguity on the appropriate choice of renormalization and factorization scales. We now perform a detailed investigation of the infrared sensitivity of the different ingredients to the single jet inclusive cross section. We show that the contribution from the second jet, ordered in transverse momentum pT, in the event is particularly sensitive to higher order effects due to implicit restrictions on its kinematics. By investigating the second-jet transverse momentum distribution, we identify large-scale cancellations between different kinematical event configurations, which are aggravated by certain types of scale choice. Taking perturbative convergence and stability as selection criteria enables us to single out the total partonic transverse energy ĤT and twice the individual jet transverse momentum 2 pT (with which ĤT coincides in Born kinematics) as the most appropriate scales in the perturbative description of single jet inclusive production.

Joint resummation of two angularities at next-to-next-to-leading logarithmic order

Multivariate analyses are emerging as important tools to understand properties of hadronic jets, which play a key role in the LHC experimental program. We take a first step towards precise and differential theory predictions, by calculating the cross section for e+e− → 2 jets differential in the angularities eα and eβ. The logarithms of eα and eβ in the cross section are jointly resummed to next-to-next-to-leading logarithmic accuracy, using the SCET+ framework we developed, and are matched to the next-to-leading order cross section. We perform analytic one-loop calculations that serve as input for our numerical analysis, provide controlled theory uncertainties, and compare our results to Pythia. We also obtain predictions for the cross section differential in the ratio eα/eβ , which cannot be determined from a fixed-order calculation. The effect of nonperturbative corrections is also investigated. Using Event2, we validate the logarithmic structure of the single angularity cross section predicted by factorization theorems at mathcal{O}left({alpha}_s^2right) , highlighting the importance of recoil for specific angularities when using the thrust axis as compared to the winner-take-all axis.

Global superscaling analysis of quasielastic electron scattering with relativistic effective mass

We present a global analysis of the inclusive quasielastic electron scattering data with a superscaling approach with relativistic effective mass. The SuSAM* model exploits the approximation of factorization of the scaling function $f^*(\psi^*)$ out of the cross section under quasifree conditions. Our approach is based on the relativistic mean field theory of nuclear matter where a relativistic effective mass for the nucleon encodes the dynamics of nucleons moving in presence of scalar and vector potentials. Both the scaling variable $\psi^*$ and the single nucleon cross sections include the effective mass as a parameter to be fitted to the data alongside the Fermi momentum $k_F$. Several methods to extract the scaling function and its uncertainty from the data are proposed and compared. The model predictions for the quasielastic cross section and the theoretical error bands are presented and discussed for nuclei along the periodic table from $A=2$ to $A=238$: $^2$H, $^3$H, $^3$He, $^4$He, $^{12}$C, $^{6}$Li, $^{9}$Be, $^{24}$Mg, $^{59}$Ni, $^{89}$Y, $^{119}$Sn, $^{181}$Ta, $^{186}$W, $^{197}$Au, $^{16}$O, $^{27}$Al, $^{40}$Ca, $^{48}$Ca, $^{56}$Fe, $^{208}$Pb, and $^{238}$U. We find that more than 9000 of the total $\sim 20000$ data fall within the quasielastic theoretical bands. Predictions for $^{48}$Ti and $^{40}$Ar are also provided for the kinematics of interest to neutrino experiments.

Impact of Thermal and Intermediate Energy Neutrons on SRAM SEE Rates in the LHC Accelerator

This paper summarizes the main results related to the single event upset and single event latch-up cross section measurements performed at CHARM in a location with a strong contribution from thermal and intermediate energy neutrons. We introduce a new experimental procedure to unfold the thermal and high-energy hadron contributions to the single event effect rate in the mixed-field environment and benchmark the result against those obtained in standard test facilities, highlighting the possible implications on the state-of-the-art component qualification.

New Volumetric Analysis Method for Stent Expansion and its Correlation With Final Fractional Flow Reserve and Clinical Outcome: An ILUMIEN I Substudy

ObjectivesThis study sought to compare conventional methodology (CM) with a newly described optical coherence tomography (OCT)-derived volumetric stent expansion analysis in terms of fractional flow reserve (FFR)-derived physiology and device-oriented composite endpoints (DoCE). BackgroundThe analysis of coronary stent expansion with intracoronary imaging has used CM that relies on the analysis of selected single cross-sections for several decades. The introduction of OCT with its ability to perform semiautomated volumetric analysis opens opportunities to redefine optimal stent expansion. MethodsA total of 291 lesions treated with post-stent OCT and FFR were enrolled. The expansion index was calculated by using a novel volumetric algorithm and was defined as: ([actual lumen area / ideal lumen area] × 100) for each frame of the stented segment. The minimum expansion index (MEI) was defined as the minimum value of expansion index along the entire stented segment. MEI and conventional lumen expansion metrics were compared for the ability to predict post-stent low FFR (<0.90) and DoCE at 1 year. ResultsThere was a stronger correlation between MEI and final FFR, compared with CM and final FFR (r = 0.690; p < 0.001) versus (r = 0.165; p = 0.044). MEI was significantly lower in patients with DoCE than those without DoCE (72.18 ± 8.23% vs. 81.48 ± 11.03%; p < 0.001), although stent expansion by CM was similar between patients with and without DoCE (85.05 ± 22.19% and 83.73 ± 17.52%; p = 0.858), respectively. ConclusionsOCT analysis of stent expansion with a newly described volumetric method, but not with CM, yielded data that were predictive of both an acute improvement in FFR-derived physiology and DoCE.

Measurements of top quark production cross-section at ATLAS

Measurements of the inclusive and differential cross-sections for top quark pair and single top production cross-sections in proton-proton collisions with the ATLAS detector at the Large Hadron Collider (LHC) are presented at centre-of-mass energies of 8 TeV and 13 TeV. These measurements reach high precision and are compared to the best available theoretical calculations. The differential measurements, including results using boosted topology, probe our understanding of top quark pair production in the TeV regime. Measurements of top-quark pair with additional jets enable the study of effect of gluon radiation, especially the measurement with additional heavy flavour jets provides test of multi-scale QCD calculation. The first evidence of single top quark production in the s-channel is quoted. Interference of top quark pair and single top productions is investigated, and the single top production cross-section in association with a Z boson is measured. Measurements of the properties of the Wtb vertex in single top quark production allow to set limits on anomalous couplings.

Effects of spray distance on the microstructure and mechanical properties of reactive plasma sprayed TiCN coatings

The objective of this study is to evaluate the effects of spray distance on the microstructure and mechanical properties of reactive plasma sprayed titanium carbonitride (TiCN) coatings under nitrogen plasma gas. For this purpose, five different distances were adopted, and the morphology (single splats, surface and cross section) and composition (phase and chemical) of as-sprayed coatings were investigated. Mechanical properties of bonding strength, hardness, elastic modulus as well as indentation toughness of coatings were systematically evaluated. Results show that all of coatings consist of TiCxN1−x (0 ≤ x ≤ 1), TiOx, amorphous graphite and CNx phases, and the amount of ternary TiCN increases as the spray distance increases. Typical microstructure of plasma sprayed coatings containing fully melted particle, partially melted particles, un-melted particles and defects (pores and cracks) are observed. As the spray distance increase, the surface morphology and splats shape change from uneven and irregular ones to relatively flat and regular “disc splats” due to the improved dwell time and sufficient melting in plasma jet. In this case, the maximum hardness about 17.8 ± 1.9 GPa, elasticity modulus about 214.5 ± 18.3 GPa and bonding strength about 24.2 ± 2.1 MPa are obtained due to the relatively high TiCN content, favorable indentation toughness and compact microstructure. As the spray distance further increases to 150 mm, irregular “fingers splats” appear, and in this case the mechanical properties of coating are worsened. Therefore, a significant influence of spray distance on the microstructure and mechanical properties of as-sprayed TiCN coating is found.

Technical note: Rapid image-based field methods improve the quantification of termite mound structures and greenhouse-gas fluxes

Abstract. Termite mounds (TMs) mediate biogeochemical processes with global relevance, such as turnover of the important greenhouse gas methane (CH4). However, the complex internal and external morphology of TMs impede an accurate quantitative description. Here we present two novel field methods, photogrammetry (PG) and cross-sectional image analysis, to quantify TM external and internal mound structure of 29 TMs of three termite species. Photogrammetry was used to measure epigeal volume (VE), surface area (AE) and mound basal area (AB) by reconstructing 3-D models from digital photographs, and compared against a water-displacement method and the conventional approach of approximating TMs by simple geometric shapes. To describe TM internal structure, we introduce TM macro- and micro-porosity (θM and θμ), the volume fractions of macroscopic chambers, and microscopic pores in the wall material, respectively. Macro-porosity was estimated using image analysis of single TM cross sections, and compared against full X-ray computer tomography (CT) scans of 17 TMs. For these TMs we present complete pore fractions to assess species-specific differences in internal structure. The PG method yielded VE nearly identical to a water-displacement method, while approximation of TMs by simple geometric shapes led to errors of 4–200 %. Likewise, using PG substantially improved the accuracy of CH4 emission estimates by 10–50 %. Comprehensive CT scanning revealed that investigated TMs have species-specific ranges of θM and θμ, but similar total porosity. Image analysis of single TM cross sections produced good estimates of θM for species with thick walls and evenly distributed chambers. The new image-based methods allow rapid and accurate quantitative characterisation of TMs to answer ecological, physiological and biogeochemical questions. The PG method should be applied when measuring greenhouse-gas emissions from TMs to avoid large errors from inadequate shape approximations.

Matriz Estratégica de Inteligência Competitiva

The objective of this work is to propose a matrix of relationship between the concepts of Actionability - the FAROUT model of (Fleisher Bensoussan, 2003) - and Integrity - (Marcial, Costa, Curvelo, 2002) in Competitive Intelligence (CI). As a methodology, a descriptive research was carried out with a single cross-section and applied to eight organizations chosen for convenience of the model, from different sectors. This is a qualitative, sectoral, exploratory study of multiple cases. The study produced a model of analysis combining actionability and integrity in a unique way. As a contribution, a proposal of a relationship matrix was prepared to verify if the companies effectively have a CI area and not espionage, speculation or storage; in the matrix, the constituent elements of the attributes of Action and Integrity are measured and classified. Among the companies surveyed, only three of them demonstrated full capacity to construct a CI area. The main contribution of this work was to keep similarity with the traditional strategic tools and to associate two essential concepts to the verification of the competitive capacity of the company.

Event selection for the measurement of the charged current muon antineutrino single pion production cross section in the T2K near detector

Event selection for the measurement of the charged current muon antineutrino single pion production cross section in the T2K near detector

Economic underpinnings of violent extremism: A cross country exploration of repeated survey data

Abstract This paper attempts to identify the economic underpinnings of the support for acts of violent extremism (VE). We explore some demographic and economic characteristics of individuals who express support for acts of violent extremism (VE) by using an extensive cross-country multi-year survey dataset ranging from 2007 to 2014. A growing body of empirical research has focused on examining the various socio-economic underpinnings of violent extremism. The results have been inconclusive, at times contradictory and often based on limited set of case studies or smaller single time period cross-section datasets. In this study we use information on a little over forty-eight thousand individuals in 12 countries to evaluate the connections between socio-economic status and support for extremism. While the impact of the socio-economic characteristics on support for violence remains inconclusive in this analysis, we do find interesting and significant results when we interact individual economic status variables with the overall economic growth of the country. Unemployment status and having lower levels of education have significant impacts on the likelihood of support for VE when interacted with country level growth rate. We conclude that inequality or a feeling of being left out-being unemployed, in higher growth countries might be the key to understanding the economic underpinnings of violent extremism.

Simple standard model extension by heavy charged scalar

We consider a Standard Model extension by a heavy charged scalar gauged only under the $U_{Y}(1)$ weak hypercharge gauge group. Such an extension, being gauge invariant with respect to the SM gauge group, is a simple special case of the well known Zee model. Since the interactions of the charged scalar with the Standard Model fermions turn out to be significantly suppressed compared to the Standard Model interactions, the charged scalar provides an example of a long-lived charged particle being interesting to search for at the LHC. We present the pair and single production cross sections of the charged scalar at different colliders and the possible decay widths for various boson masses. It is shown that the current ATLAS and CMS searches at 8 and 13 TeV collision energy lead to the bounds on the scalar boson mass of about 300--320 GeV. The limits are expected to be much larger for higher collision energies and, assuming $15~ab^{-1}$ integrated luminosity, reach about 2.7 TeV at future 27 TeV LHC thus covering the most interesting mass region.

Evolution of single carbon and glass fibrous tow cross-sections in dry and lubricated states during compaction perpendicular to the fibers

Abstract Fibrous fabrics are used in a variety of applications, among them, for structural composites. Most fabrics are efficiently manufactured from tows or yarns. During textile manufacturing or during fiber reinforced composites manufacturing, the fabrics and tows undergo several movements and deformations. Although there have been several attempts by different authors to model micro structural mechanical behavior of fabrics, they often suffer from unknown geometric dimensions at various loads or unknown materials' mechanical parameters. This paper presents a method for measuring and comparing tows (or yarns) geometrical evolution during compaction perpendicular to the fibers. The tows are compacted and dimensions are continuously measured using confocal chromatograph. Fabrics and tows of the study are composed of glass or carbon fibers, in dry or lubricated states. Volume, compacity evolutions and Poisson's ratio are extracted for a wide range of compaction levels. Tables of material characteristics and experimental data are also provided for a further use or analysis.

Multi-objective optimization based IBCS for surface roughness and textural feature in MCVE piston machining

In this paper, the effects and multi-objective optimization of process parameters on surface roughness (R a ) and textural feature in middle-convex and varying ellipse (MCVE) Al-Si alloy piston machining are analyzed. The indicator of textural feature is the variance of textural width (V t w ), which could estimate the piston skirt lubrication. The cutting force model is proposed to investigate the machining motion and turning force in single cross-section of piston showing that the turning of MCVE piston is more complex than ordinary turning. In this turning process, the key process parameters such as feed speed, spindle speed, tool elongation, and tool tip radius are optimized. Experimental data were initially collected based on the Taguchi method of experimental design, which is L25 (53) Taguchi standard orthogonal array on cutting experiments. From all of these parameters, the main effect of tool tip radius process parameter on R a or V t w is more obvious. However, the performance of R a and that of V t w is contradictory in single-objective optimization for the process parameter. By analysis of contour plot, the regions of optimal levels are small and dispersed for V t w . Hence, it is difficult to obtain optimal levels of process parameters. Under simulation, the alternation effect of cutting forces is more pronounced. Additionally, the suitable performance of V t w will be obtained while the tool tip radius (α) is small. Finally, an integrated system is proposed based on multi-optimization techniques, such as regression models, improved beta-distribution cuckoo search (IBCS) algorithm and desirability function. It shows that the average number of iterations of IBCS to achieve the optimal solution is approximately 10, which is better than that of beta-distribution cuckoo search (BCS) or cuckoo search (CS) algorithm. This result could be attributable to the fact that the parameter α0 in Levy Flights is updated by the beta-distribution of exponential decay in the proposed IBCS algorithm. Confirming experiment shows that the mean prediction error of all is no more than 15%.

Heat sink elimination and optimisation by natural convection method

ABSTRACTAll electrical and electronic components in a circuit generate a certain amount of heat when the circuit is energised by a power supply. The heat energy thus generated must be dissipated properly to maintain the surface temperature within the threshold limit to avoid early breakdown of the components. Due to miniaturisation the effective surface area for convective heat transfer gets reduced, to agitate the heat transfer rate power operated fan is required. In the present work, we have adopted a novel design of double side cross section, natural convection heat sink which has more efficiency, effectiveness and heat transfer rate compared to single side cross section of the heat sink for a given size.

Apparent diffusion coefficient for molecular subtyping of non-gadolinium-enhancing WHO grade II/III glioma: volumetric segmentation versus two-dimensional region of interest analysis

ObjectivesTo investigate if quantitative apparent diffusion coefficient (ADC) measurements can predict genetic subtypes of non-gadolinium-enhancing gliomas, comparing whole tumour against single slice analysis.MethodsVolumetric T2-derived masks of 44 gliomas were co-registered to ADC maps with ADC mean (ADCmean) calculated. For the slice analysis, two observers placed regions of interest in the largest tumour cross-section. The ratio (ADCratio) between ADCmean in the tumour and normal appearing white matter was calculated for both methods.ResultsIsocitrate dehydrogenase (IDH) wild-type gliomas showed the lowest ADC values throughout (p < 0.001). ADCmean in the IDH-mutant 1p19q intact group was significantly higher than in the IDH-mutant 1p19q co-deleted group (p < 0.01). A volumetric ADCmean threshold of 1201 × 10−6 mm2/s identified IDH wild-type with a sensitivity of 83% and a specificity of 86%; a volumetric ADCratio cut-off value of 1.65 provided a sensitivity of 80% and a specificity of 92% (area under the curve (AUC) 0.9–0.94). A slice ADCratio threshold for observer 1 (observer 2) of 1.76 (1.83) provided a sensitivity of 80% (86%), specificity of 91% (100%) and AUC of 0.95 (0.96). The intraclass correlation coefficient was excellent (0.98).ConclusionsADC measurements can support the distinction of glioma subtypes. Volumetric and two-dimensional measurements yielded similar results in this study.Key Points• Diffusion-weighted MRI aids the identification of non-gadolinium-enhancing malignant gliomas• ADC measurements may permit non-gadolinium-enhancing glioma molecular subtyping• IDH wild-type gliomas have lower ADC values than IDH-mutant tumours• Single cross-section and volumetric ADC measurements yielded comparable results in this study

Radial scaling in inclusive jet production at hadron colliders

Inclusive jet production in p-p and pbar-p collisions shows many of the same kinematic systematics as observed in single particle inclusive production at much lower energies. In an earlier study (1974) a phenomenology, called radial scaling, was developed for the single particle inclusive cross sections that attempted to capture the essential underlying physics of point-like parton scattering and the fragmentation of partons into hadrons suppressed by the kinematic boundary. The phenomenology was successful in emphasizing the underlying systematics of the inclusive particle productions. Here we demonstrate that inclusive jet production at the LHC in high-energy p-p collisions and at the Tevatron in pbar-p inelastic scattering show similar behavior. The ATLAS inclusive jet production plotted as a function of this scaling variable is studied for sqrt(s) of 2.76, 7 and 13 TeV and is compared to pbar-p inclusive jet production at 1.96 TeV measured at the CDF and D0 at the Tevatron and p-Pb inclusive jet production at the LHC ATLAS at sqrt(sNN) = 5.02 TeV. Inclusive single particle production at FNAL fixed target and ISR energies are compared to inclusive J/Psi production at the LHC measured in ATLAS, CMS and LHCb. Striking common features of the data are discussed.