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Characterization of the response function of a Si(Li) detector using an absorber technique

The non-Gaussian response function of a Si(Li) detector has been measured for characteristic Kα X-rays in the energy interval 1.5-8.6 keV using an absorber technique. The method is based on the different response to an attenuating absorber placed in front of the detector for the detector tail as compared to fully absorbed photons in the same position in the spectrum. The shape of the tail of a Kα

The relationship between the meson, baryon, photon and quark fragmentation distributions

The ideas presented in an earlier note on the relationship between the quark fragmentation distributions as measured in leptoproduction and the one particle distributions in the mesonic fragmentation regions of hadronic interactions are carried further to photoproduction and to the baryon fragmentation distributions. The results are as before interpreted in terms of a simple additive quark model w

PIXE and proton microprobe advances at the Lund Institute of Technology

A review of recent advances in high-energy ion beam analysis at the Lund Institute of Technology is presented. A nonvacuum specimen chamber allows chemical speciation using a combination of ion beam analysis and controlled heating. The development of a new versatile scanning proton microbeam based on a new dedicated accelerator, an achromatic triplet lens and an advanced specimen chamber is outlin

Ion beam thermography - analysis of chemical compounds using ion beam techniques

The analytical technique of ion beam thermography (IBT) is reported for the first time. IBT is a technique for the determination of chemical compounds. This IBT setup combines the multielemental ion beam technique's particle-induced X-ray emission (PIXE) and particle elastic scattering analysis (PESA) with thermography. A large number of elements are monitored with PIXE (Z > 14) and PESA (hydrogen

Implications of a large vector meson production on quark jet fragmentation and large p T reactions

A large vector meson production in quark jet fragmentation implies characteristic differences between the kaon and pion spectra. This prediction is verified in a recent SLAC-MIT experiment. Similar considerations are relevant for the c-quark fragmentation into D-mesons, as observed in ν scattering experiments.The difference in kaon and pion spectra provides a test of the hard quark-quark scatterin

Inner-shell ionization processes in low Z (Z ≤ 20) elements by proton bombardment

K-shell X-ray ionization cross section from thin targets of P, S, Cl, K and Ca by proton impact in the energy range of 1.0-5.0 MeV are reported using a Si(Li) detector. Our experimental results are compared with previous very scanty available data and with ECPSSR theory. Data for P are reported for the first time. Results for S, Cl and K in this wide energy range are also new data. Our results sho

Circadian onset and prognosis of myocardial infarction with non-obstructive coronary arteries (MINOCA)

Background Many acute cardiovascular events such as myocardial infarction (MI) follow circadian rhythms. Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a newly noticed entity with limited data on onset pattern and its impact on prognosis. Material and methods In this observational study of Swedish MINOCA patients registered in the SWEDEHEART registry between 2003–2013 and

An external beam PIXE/PESA setup for characterization of fine aerosols

An external beam setup has been developed for the determination of elemental concentrations in fine aerosols (aerodynamic particle diameter less than about 2 μm). Carbon, nitrogen and oxygen are determined with particle elastic scattering analysis (PESA) and, simultaneously, elements heavier than silicon with PIXE at a proton energy of 3.58 MeV. Earlier work on aerosols with PESA and most PIXE wor

Investigation of particle elastic scattering analysis as a complementary technique to pixe for aerosol characterization

The possibility of analysis by the detection of elastically scattered particles for carbon, nitrogen, oxygen and also hydrogen determination in the fine mode of aerosols has been investigated. The main objectives in this study have been to find suitable projectiles (protons or alpha particles) and projectile energy, in order to obtain separated peaks for the elements of interest and to achieve hig

Long range aerosol transport in Southern Sweden : An example of multtvariate statistical evaluation methodology

The utilization of multivariate statistical techniques is discussed with emphasis on the rather new method SIMCA, when applied to multielemental data. The procedures of scaling and normalizing are described. The data base used is from a project studying long range aerosol transport to southern Sweden. SIMCA reveals low variability in fine mode elemental composition in southerly air masses being cl

Southern scandinavian aerosol composition and elemental size distribution characteristics dependence on air-mass history

The influence of aerosol long range transport in southern Sweden was investigated from a data base consisting of simultaneous cascade impactor measurements at three sampling stations, two coastal and one inland rural location. The study focused on S and heavy metals determined by particle induced X-ray emission (PIXE) analysis. The influence of local emissions was minimized by eliminating samples

The economic consequences of neurosurgical disease in low- And middle-income countries

OBJECTIVE The objective of this study was to estimate the economic consequences of neurosurgical disease in low- and middle-income countries (LMICs). METHODS The authors estimated gross domestic product (GDP) losses and the broader welfare losses attributable to 5 neurosurgical disease categories in LMICs using two distinct economic models. The value of lost output (VLO) model projects annual GDP

On the diffractive production of charmed baryons

Arguments are presented in favour of observing charmed baryons in diffractive scattering at high energies. The cross section for production of charmed baryons is estimated to be ∼ 10-100 μb at ISR energies.

Rescattering effects in the decay of the A1

Rescattering effects in the 3π system in the A1 region are studied with a method, which fulfils unitarity and has the proper analytic structure. Fairly small effects are obtained which confirm the result found in amplitude analyses, neglecting rescattering corrections, that the phases of the JP = 1+ amplitudes vary only very little over the A1 region. Similar results hold for the Q enhancement.

Steering Magnetic Skyrmions with Currents : A Nonequilibrium Green's Functions Approach

Magnetic skyrmions, topologically protected vortex-like configurations in spin textures, are of wide conceptual and practical appeal, notably in relation to the making of so-called race-track memory devices. Skyrmions can be created, steered, and destroyed with magnetic fields and/or (spin) currents. Here the authors focus on the latter mechanism, analyzed via a microscopic treatment of the skyrmi

Urban outdoor lighting : Pedestrian perception, evaluation and behaviour in the lit environment

Walking plays an essential role in sustainable transport systems, as nearly all journeys in the urban environment incorporate walking in one way or another. In parts of the world, for long periods of the year, seasonal variation in daylight hours means that pedestrians must rely on outdoor lighting to make cities accessible after dark. However, outdoor lighting is associated with considerable ener