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MAX IV 3 GeV storage ring magnet block production series measurement results

The MAX IV 3 GeV storage ring magnets are integrated "magnet block" units consisting of several consecutive magnet elements precision-machined out of a common solid iron block. In the 3 GeV ring, there are 140 magnet blocks containing a total of 1320 magnet elements. During the manufacturing phase of the project, a field measurement was performed for each magnet element, by Hall probe and/or by ro

ESS progressing into construction

The construction of the European Spallation Source, ESS, started in summer 2014. At the site in Lund, the accelerator tunnel will be completed at the time of IPAC16, while prototyping and manufacturing or preparations for manpower contributions are going on in more 23 laboratories distributed over the 12 European countries collaborating on the accelerator project. Major technical milestones have b

Fast tracking of nonlinear dynamics in the ESS linac simulator via particle-count invariance

Real-time beam modeling has been used in accelerator diagnostics for several decades. Along the way, the theory for matrix calculations of linear forces has matured, allowing for fast calculations of a beam's momentum and position distributions. This formalism becomes complicated and ultimately breaks down with high-order beam elements like sextupoles. Such elements can be accurately modeled with

Commissioning of the harmonic cavities in the MAX IV 3 GeV ring

The MAX IV 3 GeV storage ring operates with beam of high current and ultralow emittance. These beam parameters in combination with the small effective aperture enhance possible collective beam instabilities. Three passive harmonic cavities are installed to introduce bunch lengthening and tune spread, leading to decoupling of the bunch spectrum from the machine effective impedance and mitigating in

Status of the Front Ends project at MAXIV

The MAX IV laboratory is a Swedish national laboratory for synchrotron radiation hosted by the Lund University. It will operate two storage rings to produce synchrotron light of very high intensity and quality over a broad wavelength range. A linear accelerator will feed these storage rings in topping up mode as well as serve as an electron source for a short pulse facility built on its extension.

Tango based control system at SOLARIS Synchrotron

A National Synchrotron Radiation Centre SOLARIS has been recently built in Krakow, Poland. The accelera tor is in commissioning phase. The control system is in operation and provides all functionalities required for the commissioning process. The system is based on Tango Controls and has been developed with strong collabora tion with MAX-IV, Lund Sweden and the Tango Commu nity. Protections system

Transverse coherent instabilities in storage rings with harmonic cavities

Many current and future synchrotron light sources employ harmonic cavities to lengthen the electron bunches in order to reduce the emittance dilution caused by intrabeam scattering. In some cases, the harmonic cavities may be tuned to fulfill the flat potential condition. For this condition, a large increase in the threshold currents of transverse coupled-bunch instabilities has been predicted and

SLAC FACET-II positron damping ring magnet design

The FACET-II facility, currently being designed at SLAC, will contain a small 20 m circumference, 335 MeV, positron damping ring. The ring has to fit in the existing linac tunnel, meaning that a compact lattice with short distances between magnets is required. The detailed magnet design is done in Opera-3d, with a finite element model of a full damping ring arc being simulated. This article presen

Environmental implications of transport contract choice - capacity investment and pricing under volume and capacity contracts

Inspired by the observation that capacity contracts are used by some retailers to increase their transport provider's investments in green transport solutions, we investigate and compare a service provider's optimal investment, and its environmental implications under a volume and a capacity contract respectively. We solve the service provider's investment problem under the assumption that the ret

Development blocks in innovation networks : The Swedish manufacturing industry, 1970–2007

The notion of development blocks (Dahmén, 1950, 1991) suggests the co-evolution of technologies and industries through complementarities and the overcoming of imbalances. This study proposes and applies a methodology to analyse development blocks empirically. To assess the extent and character of innovational interdependencies between industries the study combines analysis of innovation biographie

Self-delivered misinformation - Merging the choice blindness and misinformation effect paradigms

Choice blindness is the failure to detect a discrepancy between a choice and its outcome. The misinformation effect occurs when the recollection of an event changes because new, misleading information about the event is received. The purpose of this study was to merge the choice blindness and misinformation effect paradigms, and thus examine whether choice blindness can be created for individuals’

Genetic variants in CETP increase risk of intracerebral hemorrhage

OBJECTIVE: In observational epidemiologic studies, higher plasma high-density lipoprotein cholesterol (HDL-C) has been associated with increased risk of intracerebral hemorrhage (ICH). DNA sequence variants that decrease cholesteryl ester transfer protein (CETP) gene activity increase plasma HDL-C; as such, medicines that inhibit CETP and raise HDL-C are in clinical development. Here, we test the

Socioeconomic factors' effect on return to work after first stroke

OBJECTIVE: The objective of this nationwide study was to analyze how functional status and socioeconomic status affect return to work (RTW) among younger patients with first-time stroke in a Sweden.MATERIAL AND METHODS: This register-based cohort study included employed patients aged 25-55 with first-time stroke between 2008 and 2011 and primary outcome was RTW within 1 year after stroke. Data reg

Astrocyte-mediated short-term synaptic depression in the rat hippocampal CA1 area : two modes of decreasing release probability

BACKGROUND: Synaptic burst activation feeds back as a short-term depression of release probability at hippocampal CA3-CA1 synapses. This short-term synaptic plasticity requires functional astrocytes and it affects both the recently active (< 1 s) synapses (post-burst depression) as well as inactive neighboring synapses (transient heterosynaptic depression). The aim of this study was to investigate

Astrocytes impose postburst depression of release probability at hippocampal glutamate synapses

Many neurons typically fire action potentials in brief, high-frequency bursts with specific consequences for their synaptic output. Here we have examined short-term plasticity engaged during burst activation using electrophysiological recordings in acute rat hippocampal slices. We show that CA3-CA1 glutamate synapses exhibit a prominent depression of presynaptic release probability for approximate

Synaptic retrogenesis and amyloid-beta in Alzheimer's disease

Pathological hallmarks of Alzheimer's disease (AD) include synaptic and neuronal degeneration and the presence of extracellular deposits of amyloid-beta (Abeta) in senile plaques in the cerebral cortex. Although these brain lesions may be seen also in aged non-demented individuals, the increase in brain Abeta is believed by many to represent the earliest event in the disease process. Accumulating