| 1. |
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| 2. |
- Glasbey, JC, et al.
(author)
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- 2021
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swepub:Mat__t
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| 3. |
- Al Dmour, Eshraq, et al.
(author)
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Diffraction-limited storage-ring vacuum technology.
- 2014
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In: Journal of Synchrotron Radiation. - 1600-5775. ; 21:Pt 5, s. 878-883
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Journal article (peer-reviewed)abstract
- Some of the characteristics of recent ultralow-emittance storage-ring designs and possibly future diffraction-limited storage rings are a compact lattice combined with small magnet apertures. Such requirements present a challenge for the design and performance of the vacuum system. The vacuum system should provide the required vacuum pressure for machine operation and be able to handle the heat load from synchrotron radiation. Small magnet apertures result in the conductance of the chamber being low, and lumped pumps are ineffective. One way to provide the required vacuum level is by distributed pumping, which can be realised by the use of a non-evaporable getter (NEG) coating of the chamber walls. It may not be possible to use crotch absorbers to absorb the heat from the synchrotron radiation because an antechamber is difficult to realise with such a compact lattice. To solve this, the chamber walls can work as distributed absorbers if they are made of a material with good thermal conductivity, and distributed cooling is used at the location where the synchrotron radiation hits the wall. The vacuum system of the 3 GeV storage ring of MAX IV is used as an example of possible solutions for vacuum technologies for diffraction-limited storage rings.
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| 4. |
- Andersson, Åke, et al.
(author)
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Future development plans for the MAX IV light source: Pushing further towards higher brightness and coherence
- 2018
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In: Journal of Electron Spectroscopy and Related Phenomena. - : Elsevier BV. - 0368-2048. ; 224
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Journal article (peer-reviewed)abstract
- The commissioning of the MAX IV synchrotron radiation facility in Lund marks the dawn of a new generation of storage-ring-based light sources. This new generation delivers one order of magnitude higher performance and allows realization of groundbreaking experiments on a variety of systems and materials at the atomic and molecular levels. This paper reviews the conceptual basis of the MAX IV design, briefly summarizes the most recent accelerator commissioning results and focusses on exploring a future development path for the MAX IV 3 GeV storage ring aimed at achieving the diffraction limit at hard x-ray wavelengths.
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| 5. |
- Bocchetta, Carlo, et al.
(author)
-
Project Status of the Polish Synchrotron Radiation Facility Solaris
- 2011
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In: Proceedings of IPAC2011. - 9789290833666 ; , s. 3014-3016
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Conference paper (other academic/artistic)abstract
- Abstract in Undetermined The Polish synchrotron radiation facility Solaris is being built at the Jagiellonian University in Krakow. The project is based on an identical copy of the 1.5 GeV storage ring being concurrently built for the MAX IV project in Lund, Sweden. A general description of the facility is given together with a status of activities. Unique features associated with Solaris are outlined, such as infrastructure, the injector and operational characteristics.
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| 6. |
- Brosi, Miriam, et al.
(author)
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Time-resolved measurement and simulation of a longitudinal single-bunch instability at the MAX IV 3 GeV ring
- 2023
-
In: 14th International Particle Accelerator Conference. - 9783954502318 ; , s. 2685-2688
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Conference paper (other academic/artistic)abstract
- The study and understanding of collective effects plays a vital role for fourth-generation light sources. These effects mostly need to be mitigated and controlled to achieve the design operational parameters. However, they can also be utilized to gain insights into the properties of the machine. While the 3 GeV storage ring at the MAX IV light source is running in multi-bunch mode during user operation. Single-bunch operation is available in dedicated machine study shifts, providing the possibility to study collective effects at higher bunch currents. In such a current range an instability has been observed in the longitudinal plane. Above the threshold current of the instability a dynamic deformation of the bunch profile and a strong increase in energy spread occurs. Dedicated measurements were conducted with multiple diagnostic tools such as time-resolved bunch profile measurements. First simulations of the observed effects were performed with a Vlasov-Fokker-Planck solver. This contribution presents measurement results and draws a comparison to the simulations.
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| 7. |
- Cerenius, Yngve, et al.
(author)
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Status of the MAX IV Laboratory
- 2016
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In: Synchrotron Radiation News. - : Informa UK Limited. - 0894-0886 .- 1931-7344. ; 29:1, s. 34-38
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Journal article (peer-reviewed)abstract
- On the day of the 2016 summer solstice, June 21, MAX IV, the new synchrotron radiation facility in Lund, Sweden, will be inaugurated. MAX IV is setting a new standard in terms of emittance, thereby providing beamlines with the best possible brilliance and coherence. At the same time, MAX IV continues a more than three-decades-long successful history of Swedish synchrotron-radiation-based research. The activities at the present MAX-lab, which officially started when the MAX I storage ring opened for users in 1986, have been concluded with a “last beamdump” ceremony for the MAX II and MAX III storage rings on December 13, 2015, Saint Lucy's Day. In Sweden, the winter solstice is celebrated with a festival of light.
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| 8. |
- Cullinan, F. J., et al.
(author)
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The damping of transverse coherent instabilities by harmonic cavities
- 2015
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In: 6th International Particle Accelerator Conference, IPAC 2015. - 9783954501687 ; , s. 102-105
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Conference paper (peer-reviewed)abstract
- At nonzero chromaticity, the threshold current due to transverse coupled bunch instabilities in an electron storage ring is defined by intrabunch head-tail motion of higher than zeroth order. Multibunch tracking simulations predict that this threshold can be increased to several times its original value through the introduction of bunch lengthening harmonic cavities. One previously suggested explanation is the narrower spectra of the elongated bunches but reliable estimates for the threshold currents are not obtainable for anything other than rigid beam motion since the usual Sacherer formalism is not directly applicable to beams in a non-harmonic potential. A new scheme has been developed in which the decay time of a higher than zeroth order transverse head-tail mode may be estimated by taking into account the synchrotron tune spread generated by the harmonic cavity potential. This scheme is presented along with the results of numerical simulations performed in order to confirm the analytical predictions and justify the assumptions made. The extension of the scheme to more complex scenarios is also discussed.
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| 9. |
- Cullinan, F. J., et al.
(author)
-
Transverse coherent instabilities in storage rings with harmonic cavities
- 2016
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In: IPAC 2016 - Proceedings of the 7th International Particle Accelerator Conference. - 9783954501472 ; , s. 1061-1064
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Conference paper (peer-reviewed)abstract
- 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 recently, the physical content behind this stabilisation has been better understood. With this in mind, an investigation is made into the effectiveness of harmonic cavities for different machines. Frequency domain computations employing Laclare's eigenvalue method have been used to investigate the influence of several machine parameters and the results are presented.
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| 10. |
- Cullinan, F. J., et al.
(author)
-
Transverse coupled-bunch instability thresholds in the presence of a harmonic-cavity-flattened rf potential
- 2016
-
In: Physical Review Special Topics - Accelerators and Beams. - 1098-4402. ; 19:12
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Journal article (peer-reviewed)abstract
- A small vacuum chamber aperture is a present trend in the design of future synchrotron light sources. This leads to a large resistive-wall impedance that can drive coupled-bunch instabilities. Another trend is the use of passively driven cavities at a harmonic of the main radio frequency to lengthen the electron bunches in order to increase the Touschek lifetime and reduce emittance blowup due to intrabeam scattering. In some cases, the harmonic cavities may be tuned to fulfill the flat potential condition. With this condition met, it has been predicted in simulation that the threshold current for coupled-bunch resistive-wall instabilities is much higher than with no bunch lengthening at all. In this paper, the features of a bunch in the flat potential that would contribute toward this stabilization are identified and discussed. The threshold currents for these instabilities are estimated for the MAX IV 3 GeV storage ring at different values of chromaticity using macroparticle simulations in the time domain and, within the limits of the existing theory, frequency domain calculations. By comparing the results from these two methods and analyzing the spectra of the dominant head-tail modes, the impact of each of the distinguishing features of a bunch in the flat potential can be explained and quantified in terms of the change in threshold current. It is found that, above a certain chromaticity, the threshold current is determined by the radial structure of the zeroth-order head-tail mode. This happens at a lower chromaticity if the bunch length is longer.
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| 11. |
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| 12. |
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| 13. |
- Eriksson, Mikael, et al.
(author)
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The MAX IV Facility
- 2013
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In: 11th International Conference on Synchrotron Radiation Instrumentation (SRI 2012). - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 425
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Conference paper (peer-reviewed)abstract
- The MAX IV synchrotron radiation facility is currently being constructed in Lund, Sweden. The accelerator park consists of a 3 GeV linac injector and 2 storage rings operated at 1.5 and 3 GeV respectively. The linac injector will also be used for the generation of short Xray pulses. Close to 30 straight sections will be available for IDs at the rings. The three machines mentioned above are described below with some emphasis on the effort to create a very small emittance in the 3 GeV ring. Some unconventional technical solutions imposed by the emittance minimisation are discussed.
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| 14. |
- Eriksson, Mikael, et al.
(author)
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The MAX IV Synchrotron Light Source
- 2011
-
In: [Host publication title missing]. - 9789290833666 ; , s. 3026-3028
-
Conference paper (peer-reviewed)abstract
- The MAX IV synchrotron radiation facility is currently being constructed in Lund, Sweden. It consists of a 3 GeV linac injector and 2 storage rings operated at 1.5 and 3 GeV respectively. The linac injector will also be used for the generation of short X-ray pulses. The three machines mentioned above are described with some emphasis on the effort to create a very small emittance in the 3 GeV ring. Some unconventional technical solutions will also be presented.
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| 15. |
- Fernandes, Ricardo M.F. 1983-, et al.
(author)
-
Strong Spacer Length Effects on The Thermal Behavior and Mesophase Formation By Gemini Surfactants
- 2015
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Other publication (other academic/artistic)abstract
- The self-aggregation properties in aqueous solution of gemini surfactants of the type alkanediyl-α,ω-bis(dodecyldimethylammonium bromides), 12-s-12, have been extensively reported and are known to be significantly influenced by the number of methylene groups, s, of the covalent spacer. In contrast, the thermal behavior of the anhydrous compounds as a function of varying s has not been investigated in a similarly systematic way. Herein, we present the thermal phase behavior of eight compounds of the 12-s-12 family (with s = 2-6, 8, 10 and 12), resorting to differential scanning calorimetry (DSC), polarized light microscopy (PLM) and X-ray diffraction (XRD). We find that compounds with either the shortest spacer, s = 2, or the longest ones—8, 10 and 12—form several smectic liquid-crystalline phases prior to isotropization to the liquid phase, with appearance of oily streaks, focal conics, mosaic and fan-shaped birefringent textures. In sharp contrast, gemini compounds with intermediate spacers, s = 3-6, decompose and do not form any disordered, fluid mesophases. Both the DSC thermodynamic parameters for the phase transitions and d00l spacings obtained from XRD show non-monotonic trends with spacer variation, indicating that there are significant differences in solid-state packing and melting process. Plausible molecular packing arrangements in the solid-state are presented, consistent with the XRD information and geometric considerations, and their influence on the phase behavior trends critically discussed.
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| 16. |
- Fernandes Tavares, Pedro, et al.
(author)
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Equilibrium bunch density distribution with passive harmonic cavities in a storage ring
- 2014
-
In: Physical Review Special Topics. Accelerators and Beams. - 1098-4402. ; 17:6
-
Journal article (peer-reviewed)abstract
- The MAX IV storage rings, currently under construction in Lund, Sweden, will use third harmonic cavities operated passively to lengthen the bunches and alleviate collective instabilities. These cavities are an essential ingredient in the MAX IV design concept and are required for achieving the final design goals in terms of stored current, beam emittance, and beam lifetime-such performance challenges are in fact common to all recent ultralow emittance storage ring designs and harmonic cavities are currently under consideration in several laboratories. In this paper, we report on parametric studies comparing different harmonic cavity settings in terms of the resulting bunch length, peak bunch density, and incoherent synchrotron frequency spread for the MAX IV 3 GeV ring. The equilibrium longitudinal bunch density distribution was calculated by establishing a self-consistent equation for the bunch form factor, describing the bunch shape. The calculations are fully self-consistent in the sense that not only the amplitude but also the phase of the waves excited by the beam in the harmonic cavity were assumed to be a function of the bunch shape, which allowed us to explore a wide parameter range not restricted to the region close to the conditions for which the first and second derivatives of the total rf voltage are zero at the synchronous phase. Our results indicate that up to a factor 5 increase in rms bunch length is achievable with a purely passive system for the MAX IV 3 GeV ring while keeping a relatively large harmonic cavity detuning, thus limiting the unavoidable Robinson antidamping rate from the fundamental mode of a passively operated harmonic cavity to values below the synchrotron radiation damping rate. The paper is complemented by results of measurements performed in the MAX III storage ring, which showed good agreement with calculations following the fully self-consistent approach.
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| 17. |
- Fernandes Tavares, Pedro, et al.
(author)
-
The MAX IV storage ring project.
- 2014
-
In: Journal of Synchrotron Radiation. - 1600-5775. ; 21:Pt 5, s. 862-877
-
Journal article (peer-reviewed)abstract
- The MAX IV facility, currently under construction in Lund, Sweden, features two electron storage rings operated at 3 GeV and 1.5 GeV and optimized for the hard X-ray and soft X-ray/VUV spectral ranges, respectively. A 3 GeV linear accelerator serves as a full-energy injector into both rings as well as a driver for a short-pulse facility, in which undulators produce X-ray pulses as short as 100 fs. The 3 GeV ring employs a multibend achromat (MBA) lattice to achieve, in a relatively short circumference of 528 m, a bare lattice emittance of 0.33 nm rad, which reduces to 0.2 nm rad as insertion devices are added. The engineering implementation of the MBA lattice raises several technological problems. The large number of strong magnets per achromat calls for a compact design featuring small-gap combined-function magnets grouped into cells and sharing a common iron yoke. The small apertures lead to a low-conductance vacuum chamber design that relies on the chamber itself as a distributed copper absorber for the heat deposited by synchrotron radiation, while non-evaporable getter (NEG) coating provides for reduced photodesorption yields and distributed pumping. Finally, a low main frequency (100 MHz) is chosen for the RF system yielding long bunches, which are further elongated by passively operated third-harmonic Landau cavities, thus alleviating collective effects, both coherent (e.g. resistive wall instabilities) and incoherent (intrabeam scattering). In this paper, we focus on the MAX IV 3 GeV ring and present the lattice design as well as the engineering solutions to the challenges inherent to such a design. As the first realisation of a light source based on the MBA concept, the MAX IV 3 GeV ring offers an opportunity for validation of concepts that are likely to be essential ingredients of future diffraction-limited light sources.
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| 18. |
- Johansson, Martin, et al.
(author)
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MAX IV 3 GeV storage ring magnet block production series measurement results
- 2015
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In: 6th International Particle Accelerator Conference, IPAC 2015. - 9783954501687 ; , s. 3069-3071
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Conference paper (peer-reviewed)abstract
- The magnet design of the MAX IV 3 GeV storage ring replaces the conventional support girder + discrete magnets scheme of previous third-generation synchrotron radiation light sources with a compact (Ø25 mm aperture) integrated design having several consecutive magnet elements precision-machined out of a common solid iron block. The production series of 140 integrated magnet block units, which was totally outsourced to industry, was completed mid-2014. This article presents mechanical and magnetic field measurement results of the full production series.
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| 19. |
- Johansson, Martin, et al.
(author)
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MAX IV 3 GeV storage ring magnet block production series measurement results
- 2016
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In: IPAC 2016 - Proceedings of the 7th International Particle Accelerator Conference. - 9783954501472 ; , s. 1157-1159
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Conference paper (peer-reviewed)abstract
- 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 rotating coil. This article presents an overview of the magnetic field measurement results that were obtained for the full production series.
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| 20. |
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| 21. |
- Klementiev, Konstantin, et al.
(author)
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Wiggler radiation at a low-emittance storage ring and its usage for X-ray absorption spectroscopy
- 2022
-
In: Journal of Synchrotron Radiation. - 0909-0495. ; 29, s. 462-469
-
Journal article (peer-reviewed)abstract
- Awiggler is a high-power insertion device that was used in the past to produce a smooth wide-band X-ray spectrum. It is widely believed that on low-emittance synchrotrons this X-ray source loses its spatial and spectral homogeneity and therefore becomes less ideal than a scanning undulator. In this paper, we report on experimental and computational studies of an in-vacuum wiggler installed on the first fourth-generation synchrotron MAX IV. We investigate how several physical parameters affect the wiggler spectrum and propose a combination of a few of them that results in significant spectral smoothing. We also examine EXAFS spectra for possible distortions originating from the source imperfection. For this purpose, we scrutinize samples of various homogeneity. We conclude that wigglers are still an appropriate class of insertion devices, also on low-emittance synchrotrons.
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| 22. |
- Leemann, Simon, et al.
(author)
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Commissioning of the MAX IV Light Source
- 2016
-
In: IPAC 2016 - Proceedings of the 7th International Particle Accelerator Conference. - 9783954501472 ; , s. 11-15
-
Conference paper (other academic/artistic)abstract
- The first of the so-called diffraction-limited storage rings (DLSRs), MAX I V, has now gone into operation. For this ring, a multibend achromat (MBA) lattice is employed in order to achieve a small electron beam emittance. Several non-conventional technical system solutions have been introduced in order to reduce size, cost, assembly time, installation effort and to increase the ring robustness. Examples of this are solid magnet blocks housing several magnet items, a fully NEG-coated vacuum system and a low frequency RF system. The commissioning started in late August 2015. Several base-line parameters have now been reached like a sufficiently high stored circulating current, beam lifetime and beam quality for beamline commissioning. The MBA concept and the operation of the non-conventional solutions technical systems are verified. This article describes some of the technical solutions chosen and the early commissioning results.
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| 23. |
- Mansten, Erik, et al.
(author)
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Cancellation of klystron-induced energy and arrival-time variations in linear accelerators with arc-type bunch compressors
- 2024
-
In: Physical Review Accelerators and Beams. - 2469-9888. ; 27:4
-
Journal article (peer-reviewed)abstract
- We explain how the accelerating field amplitude and phase vary with modulator voltage in pulsed radio frequency high-power amplifiers based on klystron tubes. Changes in modulator voltage give rise to correlated changes of amplitude and phase, affecting the properties of the accelerated beam, in particular energy, arrival time, and bunch duration. We show, both theoretically and experimentally, that there exists a postcrest acceleration phase (the magic angle) where the changes of beam energy due to phase and amplitude shifts caused by modulator-voltage variations cancel out. When accelerating at the magic angle, the klystron modulator voltage jitter no longer contributes to energy and arrival-time jitter in the accelerator. Off-crest operation at the magic angle can be implemented for bunch compression schemes in accelerators with arc-type bunch compressors, which have positive momentum compaction. The experimental results, obtained at the MAX IV laboratory, show the benefit of operating close to the magic angle in arc-type bunch compressors. In a direct measurement of normalized electron-energy jitter, the energy jitter was reduced by a factor of 1.8 down to 8.2×10-5 when operating at the magic angle.
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| 24. |
- Pedro, Joana Reis, et al.
(author)
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Transient gain of function of cannabinoid CB1 receptors in the control of frontocortical glucose consumption in a rat model of Type-1 diabetes
- 2020
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In: Brain Research Bulletin. - : Elsevier BV. - 0361-9230. ; 161, s. 106-115
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Journal article (peer-reviewed)abstract
- Here we aimed to unify some previous controversial reports on changes in both cannabinoid CB1 receptor (CB1R) expression and glucose metabolism in the forebrain of rodent models of diabetes. We determined how glucose metabolism and its modulation by CB1R ligands evolve in the frontal cortex of young adult male Wistar rats, in the first 8 weeks of streptozotocin-induced type-1 diabetes (T1D). We report that frontocortical CB1R protein density was biphasically altered in the first month of T1D, which was accompanied with a reduction of resting glucose uptake ex vivo in acute frontocortical slices that was normalized after eight weeks in T1D. This early reduction of glucose uptake in slices was also restored by ex vivo treatment with both the non-selective CB1R agonists, WIN55212−2 (500 nM) and the CB1R-selective agonist, ACEA (3 μM) while it was exacerbated by the CB1R-selective antagonist, O-2050 (500 nM). These results suggest a gain-of-function for the cerebrocortical CB1Rs in the control of glucose uptake in diabetes. Although insulin and IGF-1 receptor protein densities remained unaffected, phosphorylated GSKα and GSKβ levels showed different profiles 2 and 8 weeks after T1D induction in the frontal cortex. Altogether, the biphasic response in frontocortical CB1R density within a month after T1D induction resolves previous controversial reports on forebrain CB1R levels in T1D rodent models. Furthermore, this study also hints that cannabinoids may be useful to alleviate impaired glucoregulation in the diabetic cortex.
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| 25. |
- Robert, Aymeric, et al.
(author)
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MAX IV Laboratory
- 2023
-
In: European Physical Journal Plus. - 2190-5444. ; 138:6
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Journal article (peer-reviewed)abstract
- MAX IV Laboratory is a Swedish national synchrotron radiation facility that comprises three accelerators with varying characteristics. One of the accelerators, the 3 GeV storage ring, is the world’s first fourth-generation ring and pioneered the use of the multibend achromat lattice to provide access to ultrahigh brightness X-rays. MAX IV aims to stay at the forefront of the current and future research needs of its multidisciplinary user community, principally located in the Nordic and Baltic regions. Our 16 beamlines currently offer and continue to develop modern X-ray spectroscopy, scattering, diffraction, and imaging techniques to address scientific problems of importance to society.
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| 26. |
- Skripka, G., et al.
(author)
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Commissioning of the harmonic cavities in the MAX IV 3 GeV ring
- 2016
-
In: IPAC 2016 - Proceedings of the 7th International Particle Accelerator Conference. - 9783954501472 ; , s. 2911-2913
-
Conference paper (peer-reviewed)abstract
- 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 instabilities by Landau damping respectively. In this paper we present the first results of the commissioning of the passive third harmonic cavities in the MAX IV 3 GeV ring. The additional harmonic cavity potential significantly improved the beam lifetime. First observations of the harmonic cavity effect on the damping of collective beam instabilities are discussed.
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| 27. |
- Skripka, Galina, et al.
(author)
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Simultaneous computation of intrabunch and interbunch collective beam motions in storage rings
- 2016
-
In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 806, s. 221-230
-
Journal article (peer-reviewed)abstract
- We present the multibunch tracking code mbtrack developed to simulate, in 6-dimensional phase space, single- and multibunch collective instabilities driven by short- and long-range wakefields in storage rings. Multiple bunches, each composed of a large number of macroparticles, are tracked, allowing simulation of both intra- and interbunch motions. Besides analytical impedance models, the code allows employment of numerical wake potentials computed with electromagnetic (EM) field solvers. The corresponding impedances are fitted to a number of known analytical functions and the coefficients obtained in the fit are used as an input to the code. mbtrack performs a dynamic treatment of long-range resistive-wall and harmonic cavity fields, which are likely to be the two major factors impacting multibunch collective motions in many present and future ring-based light sources. Furthermore, it is capable of simulating beam-ion interactions as well as transverse bunch-by-bunch feedback. We describe the physical effects considered in the code and their implementation, which makes use of parallel processing to significantly shorten the computation time. mbtrack is benchmarked against other codes and applied to the MAX IV 3 GeV ring as an example, where the importance of the interplay of various physical effects as well as coupling among different degrees of freedom is demonstrated.
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| 28. |
- Skripka, Galina, et al.
(author)
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Transverse Instabilities in the MAX IV 3 GeV Ring
- 2014
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In: Proceedings of IPAC2014, Dresden, Germany. - 9783954501328 ; , s. 1689-1691
-
Conference paper (other academic/artistic)abstract
- Collective effects in MAX IV 3 GeV storage ring are strongly enhanced by the combination of low emittance, high current and small effective aperture. Three passive harmonic cavities (HC) are introduced to lengthen the bunches, by which beam stabilization is anticipated via decoupling to high frequency wakes, along with Landau damping. The role of the transverse impedance budget of the MAX IV 3 GeV storage ring as a source of collective beam instabilities was determined. With the help of the macroparticle multibunch tracking code mbtrack that directly uses the former as input, we studied the influence of geometric and resistive wall impedance in both transverse planes, as well as that of chromaticity shifting. A fully dynamic treatment of the passive harmonic cavities developed for this study allowed us to evaluate their effectiveness under varying beam conditions.
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