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Search for new phenomena with large jet multiplicities and missing transverse momentum using large-radius jets and flavour-tagging at ATLAS in 13 TeV pp collisions

A search is presented for particles that decay producing a large jet multiplicity and invisible particles. The event selection applies a veto on the presence of isolated electrons or muons and additional requirements on the number of b-tagged jets and the scalar sum of masses of large-radius jets. Having explored the full ATLAS 2015-2016 dataset of LHC proton-proton collisions at s=13 TeV, which c

Measurement of the Drell-Yan triple-differential cross section in pp collisions at √s=8 TeV

This paper presents a measurement of the triple-differential cross section for the Drell-Yan process Z/γ* → ℓ+ℓ− where ℓ is an electron or a muon. The measurement is performed for invariant masses of the lepton pairs, mℓℓ, between 46 and 200 GeV using a sample of 20.2 fb−1 of pp collisions data at a centre-of-mass energy of s=8 TeV collected by the ATLAS detector at the LHC in 2012. The data are p

Determination of the strong coupling constant αs from transverse energy–energy correlations in multijet events at √s=8TeV using the ATLAS detector

Measurements of transverse energy–energy correlations and their associated asymmetries in multi-jet events using the ATLAS detector at the LHC are presented. The data used correspond to s=8TeV proton–proton collisions with an integrated luminosity of 20.2fb-1. The results are presented in bins of the scalar sum of the transverse momenta of the two leading jets, unfolded to the particle level and c

Charged-particle multiplicity distributions over a wide pseudorapidity range in proton-proton collisions at √s= 0.9, 7, and 8 TeV

We present the charged-particle multiplicity distributions over a wide pseudorapidity range (-3.45.0) for pp collisions at s=0.9,7, and 8 TeV at the LHC. Results are based on information from the Silicon Pixel Detector and the Forward Multiplicity Detector of ALICE, extending the pseudorapidity coverage of the earlier publications and the high-multiplicity reach. The measurements are compared to r

Shrinking targets in parametrised families

We consider certain parametrised families of piecewise expanding maps on the interval, and estimate and sometimes calculate the Hausdorff dimension of the set of parameters for which the orbit of a fixed point has a certain shrinking target property. This generalises several similar results for β-transformations to more general non-linear families. The proofs are based on a result by Schnellmann o

The electronic structure of negatively charged fullerenes : From monomers to dimers

Multiconfigurational second order perturbation theory was employed in order to describe the ground and excited states of negatively charged fullerenes C60 and fullerene dimers C120. The calculations were performed for all possible spin states. The obtained results can be used to understand the electronic structure of fullerides.

Mapping the dominant regions of the phase space associated with c c - production relevant for the prompt atmospheric neutrino flux

We present a detailed mapping of the dominant kinematical domains contributing to the prompt atmospheric neutrino flux at high neutrino energies by studying their sensitivity to the cuts on several kinematical variables crucial for charm production in cosmic ray scattering in the atmosphere. This includes the maximal center-of-mass energy for proton-proton scattering, the longitudinal momentum fra

High-energy x-ray diffraction from surfaces and nanoparticles

High-energy surface-sensitive x-ray diffraction (HESXRD) is a powerful high-energy photon technique (E > 70 keV) that has in recent years proven to allow a fast data acquisition for the 3D structure determination of surfaces and nanoparticles under in situ and operando conditions. The use of a large-area detector facilitates the direct collection of nearly distortion-free diffraction patterns over

Differential timing and latitudinal variation in sex ratio of Aquatic Warblers during the autumn migration

Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year bi

Helicity-dependent terahertz emission spectroscopy of topological insulator S b2 T e3 thin films

We report on helicity-dependent terahertz emissions that originate from the helicity-dependent photocurrents in topological insulator Sb2Te3 thin films due to ultrafast optical excitation. The polarity of the emitted terahertz radiation is controlled by both the incident angle and the helicity of optical pulses. Using an unprecedented decomposition-recombination procedure in the time domain, the s

Can domestic production of iLUC-free feedstock from arable land supply Sweden’s future demand for biofuels?

The increasing biofuel production from agricultural crops has been suggested to cause indirect land use change (iLUC). This increases interest in biofuel feedstocks that qualify as iLUC-free: (1) residues without a market, (2) crops from previously unused arable land, (3) additional crops and (4) biomass from intensified production. In the present study, biofuel potential from such feedstocks was

State-space models and stored electromagnetic energy for antennas in dispersive and heterogeneous media

Accurate and efficient evaluation of the stored energy is essential for Q factors, physical bounds, and antenna current optimization. Here it is shown that the stored energy can be estimated from quadratic forms based on a state-space representation derived from the electric and magnetic field integral equations. The derived expressions are valid for small antennas embedded in temporally dispersiv

The association between medical diagnosis and caregiver burden : a cross-sectional study of recipients of informal support and caregivers from the general population study ‘Good Aging in Skåne’, Sweden

Background: Different kinds of chronic diseases might imply different dimensions of caregiver burden, not previously described among the caregivers to recipients from the general elder population. Aim: The main objective was to examine differences in burden between the 343 caregivers to persons with different diagnoses. Methods: A group of elderly recipients of informal care (n = 343) from the gen

Analysis of heat losses in underground tunnels for preheating of ventilation air

Methods for calculation of thermal conditions and heat loss parameter for an underground tunnel into surrounding sub-soil were developed in the first half and in the middle of the 20th century [18-20], when the study of complex heat-and mass exchange processes between underground tunnel, sub-soil and outdoor air was started. In a tunnel it is important to meet specific microclimate parameters such

Multi-scale mechanics of granular solids from grain-resolved X-ray measurements

This work discusses an experimental technique for studying the mechanics of three-dimensional (3D) granular solids. The approach combines 3D X-ray diffraction and X-ray computed tomography to measure grain-resolved strains, kinematics and contact fabric in the bulk of a granular solid, from which continuum strains, grain stresses, interparticle forces and coarse-grained elasto-plastic moduli can b

Change Detection Method for High Resolution Remote Sensing Images Using Random Forest

Studies based on object-based image analysis (OBIA) representing the paradigm shift in remote sensing image change detection (CD) have achieved remarkable progress in the last decade. Their aim has been developing more intelligent interpretation analysis methods in the future. The prediction effect and performance stability of random forest (RF), as a new kind of machine learning algorithm, are be

Calibration and testing of a portable NaI(Tl) gamma-ray spectrometer-dosimeter for evaluation of terrestrial radionuclides and 137Cs contributions to ambient dose equivalent rate outdoors

A commercially available NaI(Tl) based spectrometer-dosimeter has been used to separate contributions of the terrestrial radionuclides (238U series, 232Th series and 40K) and 137Cs to the total ambient dose equivalent rate (ADER), Ḣ*(10) , outdoors. The device had been initially calibrated by the manufacturer to measure: 1) the total ADER; 2) activity concentrations of 226Ra, 232Th, 40K and ‘effec

Russian practical guidance on radiological support for justification of X-ray and nuclear medicine examinations

An important part of the justification process is assessment of the radiation risks caused by exposure of a patient during examination. The authors developed official national methodology both for medical doctors and sanitary inspectors called ‘assessmentof radiation risks of patients undergoing diagnostic examinations with the use of ionizing radiation’. The document addressespatients of various

Automatic lung segmentation in functional SPECT images using active shape models trained on reference lung shapes from CT

Objective: Image segmentation is an essential step in quantifying the extent of reduced or absent lung function. The aim of this study is to develop and validate a new tool for automatic segmentation of lungs in ventilation and perfusion SPECT images and compare automatic and manual SPECT lung segmentations with reference computed tomography (CT) volumes. Methods: A total of 77 subjects (69 patien