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Evolution effects in Z0 fragmentation into charmonium

In Z0 decay into prompt charmonium, i.e. charmonium not originating from B-meson decays, the most important contribution is expected to come from colour-octet mechanisms. However, previous fixed-order calculations of the colour-octet contribution contain large logarithms which, in a more complete treatment, should be resummed to all orders. We study this resummation by using a Monte Carlo QCD casc

Quark Jet Fragmentation

A semiclassical model is presented for the way the energy of a fast quark is transformed into observable hadrons. It reproduces the features of 1 + 1 dimensional QED (the Schwinger model) concerning a flat rapidity distribution in the central region. In particular the model predicts that the probability to find a meson containing a leading quark is independent of the Feynman scaling variable. Also

Drop size distribution and LWC in Po valley fog

In this paper results are presented of ground-based fog microphysical measurements obtained during the CHEMDROP experiment in the Po Valley (Northern Italy) in November 1994. Altogether about 85 hours of drop microphysical data are analyzed. At the beginning of the experiment a comparison of some of the different microphysical instruments, operated during the experiment, was performed. It has reve

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

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

Socioeconomic circumstances and incidence of chronic obstructive pulmonary disease (COPD) in an urban population in Sweden

The association between socioeconomic circumstances and incidence of chronic obstructive pulmonary disease (COPD) was investigated in an urban population in Sweden. The study included all 40–89 year-old inhabitants in Malmö, Sweden (N = 117,479) without previous hospitalization due to COPD, who were followed over 14 years for COPD related hospital admissions. The Malmö Preventive Project (MPP) co

En kunskapsarena och dess aktörer : Under strecket och kunskapscirkulation i 1960-talets offentlighet

I denna uppsats anläggs ett kunskapshistoriskt perspektiv på Svenska Dagbladets dagliga essäsida Under strecket och 1960-talets kunskapscirkulation. Genom att studera några tongivande skribenter och ett stort antal understreckare karakteriseras den akademiska kunskapens plats och form i tidens svenska offentlighet. På ett teoretiskt plan griper uppsatsen in i den vetenskapliga diskussionen om kuns

Triple collinear emissions in parton showers

A framework to include triple collinear splitting functions into parton showers is presented, and the implementation of flavor-changing next-to-leading-order (NLO) splitting kernels is discussed as a first application. The correspondence between the Monte Carlo integration and the analytic computation of NLO DGLAP evolution kernels is made explicit for both timelike and spacelike parton evolution.

Precision studies of observables in pp→ W→ lν l and pp→ γ, Z→ l + l - processes at the LHC

This report was prepared in the context of the LPCC Electroweak Precision Measurements at the LHC WG (https://lpcc.web.cern.ch/lpcc/index.php?page=electroweak_wg) and summarizes the activity of a subgroup dedicated to the systematic comparison of public Monte Carlo codes, which describe the Drell–Yan processes at hadron colliders, in particular at the CERN Large Hadron Collider (LHC). This work re

Characteristics of haze, mist and fog

An aerosol and fog data set from a field experiment in November 1994 at San Pietro Capofiume, Northern Italy was analysed. With objective criteria developed from visibility measurements average aerosol characteristics in the dry and wet state were calculated for haze, mist and fog conditions which can be seen as representative for continental air masses in an industrialised region. Dry particle si

Phase partitioning of aerosol constituents in cloud based on single-particle and bulk analysis

Single-particle analysis, performed by laser microprobe mass spectrometry and bulk analytical techniques were used to study aerosol-cloud interactions within the third field campaign of the EUROTRAC subproject 'ground-based cloud experiments' at the Great Dun Fell, Cumbria, U.K. in spring 1993. The shape of the ridge made it possible for ground-based instrumentation to sample similar parcels of ai