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Pushing the MAX IV 3 GeV storage ring brightness and coherence towards the limit of its magnetic lattice

The MAX IV 3 GeV storage ring is presently being commissioned and crucial parameters such as machine functions, emittance, and stored current have either already been reached or are approaching their design specifications [1, 2]. Once the baseline performance has been achieved, a campaign will be launched to further improve the brightness and coherence of this storage ring for typical x-ray users.

Exclusive vector meson photoproduction at the LHC and a future circular collider : A closer look on the final state

Over the past years, the LHC experiments have reported experimental evidence for processes associated to photon-photon and photon-hadron interactions, showing their potential to investigate the production of low- and high-mass systems in exclusive events. In the particular case of the photoproduction of vector mesons, the experimental study of this final state is expected to shed light on the desc

The vacuum system of MAX IV storage rings : Installation and conditioning

The installation of the vacuum system of the 3 GeV storage ring was started in November 2014 and finished in May 2015. In August 2015 the commissioning of the storage ring started, the first stored beam has been achieved on the 15th of September 2015. The installation of the vacuum system of the 1.5 GeV storage ring was done from September 2015 and the main part finished in December 2015, the conn

4D dosimetry and motion management in clinical radiotherapy

Many novel modulated radiation treatment techniques are sensitive to patient motion which may degrade the dose distribution considerably. As there may be a simultaneous movement of the tumour and treatment machine, undesired heterogeneities in the dose distribution can be resulted. Methods to estimate the dosimetric effect of motion and treatment deliveries for both photons and protons are needed.

Uncertainty quantification of propagation in evaporation ducting

The Fourier split-step method is used for solving parabolic equations in, for example, computational electromagnetics. In this paper we develop a spectral based Fourier split-step method that will take a limited degree of information with regard to the refractive index of the atmosphere into account.

Heat transfer and flow structure in a latticework duct with different sidewalls

Heat transfer characteristics in a latticework duct with various sidewalls are numerically investigated. The crossing angle is 90 deg and the number of subchannels is eleven on both the pressure side and suction side for each latticework duct. The thickness of the ribs is 8 mm and the distance between adjacent ribs is 24 mm. The investigation is conducted for various Reynolds numbers (11,000 to 55

Investigation to improve efficiency and availability in control and operation of superconducting cavity at ESS

The higher efficiency and higher availability (fault-tolerant oriented) of RF & Cavity system (with beam loading) to operate at, the more dynamic details needs to be identified, so as to have the abilities (a) to work at nonlinearities, (b) to work close to limitation, and (c) to change operation point quickly and correctly. Dynamic detail identifications rely heavily on high precision measuri

Effect of the broken rib locations on the heat transfer and fluid flow in a rotating latticework duct

A numerical method was used to study the effect of the broken rib locations on the heat transfer and flow structure in the latticework duct with various rotational numbers. The latticework duct had eleven subchannels on both the pressure side and the suction side. The crossing angle for each subchannel was 45 deg. The numerical studies were conducted with five different broken rib locations and si

Spectra, current flow, and wave-function morphology in a model PT -symmetric quantum dot with external interactions

In this paper we use numerical simulations to study a two-dimensional (2D) quantum dot (cavity) with two leads for passing currents (electrons, photons, etc.) through the system. By introducing an imaginary potential in each lead the system is made symmetric under parity-time inversion (PT symmetric). This system is experimentally realizable in the form of, e.g., quantum dots in low-dimensional se

Efficient charge generation from triplet excitons in metal-organic heterojunctions

The success of many emerging molecular electronics concepts hinges on an atomistic understanding of the underlying electronic dynamics. We employ picosecond time-resolved x-ray photoemission spectroscopy (tr-XPS) to elucidate the roles of singlet and triplet excitons for photoinduced charge generation at a copper-phthalocyanine-C60 heterojunction. Contrary to common belief, fast intersystem crossi

A Direct Numerical Simulation Investigation of the One-Phase Flow in a Simplified Emulsification Device

More detailed investigation of the flow inside emulsification devices, e.g., High-pressure homogenizers (HPHs) helps the industry to broaden the fundamental understanding of the working principle of these machines which in turn will pave the road to increase the breakup efficiency of emulsification processes. Direct numerical simulation (DNS) is not deemed as a practical method in industry due to

Cross section asymmetry of the 12C(γ; p0)11B and 12C(γ; p1)11B reactions at photon energies 40...55 MeV

The asymmetry of the cross section of the 12C(γ; p0)11B and 12C(γ; p1)11B reactions has been measured in the energy range 40...55MeV using linearly polarized tagged photons of the MAX-lab facility. The asymmetry of the process 12C(γ; p0)11B is Σ ∼ 0:85, that implies one-particle reaction mechanism. The asymmetry of the reaction 12C(γ; p1)11B is smaller, Σ ∼ 0.6...0.7, that may be due to the strong

Disentangling transient charge order from structural dynamics contributions during coherent atomic motion studied by ultrafast resonant x-ray diffraction

We report on the ultrafast dynamics of charge order and structural response during the photoinduced suppression of charge and orbital order in a mixed-valence manganite. Employing femtosecond time-resolved resonant x-ray diffraction below and at the Mn K absorption edge, we present a method to disentangle the transient charge order and structural dynamics in thin films of Pr0.5Ca0.5MnO3. Based on

Time- And energy-resolved effects in the boron-10 based multi-grid and helium-3 based thermal neutron detectors

The boron-10 based multi-grid detector is being developed as an alternative to helium-3 based neutron detectors. At the European Spallation Source, the detector will be used for time-of-flight neutron spectroscopy at cold to thermal neutron energies. The objective of this work is to investigate fine time- and energy-resolved effects of the Multi-Grid detector, down to a few µeV, while comparing it

α -spectroscopy studies of the new nuclides Pt 165 and Hg 170

The new nuclides Pt165 and Hg170 were produced in the reactions Mo92(Kr78,5n) and Ru96(Kr78,4n) at bombarding energies of 418 MeV and 390 MeV, respectively. For Hg170 an α-particle energy of Eα=7590(30)keV and half-life of t1/2=0.08-0.04+0.40ms were deduced, while for Pt165 the corresponding values were 7272(14) keV and 0.26-0.09+0.26ms. Comparison of the reduced α-decay widths with systematics in

Identification of a 6.6 μ s isomeric state in Ir 175

An experiment has been performed to study excited states in the neutron-deficient nucleus Ir175 via the use of the JUROGAM II high-purity germanium detector array and the RITU gas-filled separator at JYFL, Jyväskylä. By using isomer tagging, an isomeric state with a half-life of 6.58(15) μs has been observed in Ir175 for the first time. It has been established that the isomer decays via a 45.2 (E1

Low Risk of Procedure Related Major Amputation Following Revascularisation for Intermittent Claudication : A Population Based Study

Objective: To investigate the risk of procedure-related major amputation attributable to revascularization for intermittent claudication (IC) in a population-based observational cohort study. Methods: All patients who underwent open or endovascular lower limb revascularisation for IC in Sweden between 12 May 2008 and 31 December 2012 were identified from the Swedish National Quality Registry for V

Impact of Preoperative Symptoms and Revascularized Arterial Segment in Patients With Chronic Limb-Threatening Ischemia

Background: Little is known about the relative impact of the preoperative symptoms rest pain and tissue loss, and of the arterial segment revascularized, on amputation rate and mortality in patients with chronic limb-threatening ischemia (CLTI). We wanted to investigate this topic further. Method: This population-based observational cohort study involved 10 419 patients revascularized for CLTI in

Editor's Choice – Impact of Comorbidity, Medication, and Gender on Amputation Rate Following Revascularisation for Chronic Limb Threatening Ischaemia

Objective/background: Chronic limb threatening ischaemia (CLTI) has a high risk of amputation and mortality. Increased knowledge on how sex, comorbidities, and medication influence these outcomes after revascularisation may help optimise results and patient selection. Methods: This population based observational cohort study included all individuals revascularised for CLTI in Sweden during a five

Amputation Rates, Mortality, and Pre-operative Comorbidities in Patients Revascularised for Intermittent Claudication or Critical Limb Ischaemia : A Population Based Study

Objectives The aims of this population based study were to describe mid- to long-term amputation risk, cumulative incidence of death or amputation, and differences in pre-operative comorbidities in patients revascularised for lower limb peripheral artery disease (PAD). Methods This was an observational cohort study. Data from the Swedish National Quality Registry for Vascular Surgery (Swedvasc) we