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Background: Magnetic resonance‐guided proton therapy is promising, as it combines high‐contrast imaging of soft tissue with highly conformal dose delivery. However, proton dosimetry in magnetic fields using ionization chambers is challenging since the dose distribution as well as the detector response are perturbed. Purpose: This work investigates the effect of the magnetic field on the ionization chamber response, and on the polarity and ion recombination correction factors, which are essential for the implementation of a proton beam dosimetry protocol in the presence of magnetic fields. Methods: Three Farmer‐type cylindrical ionization chambers, the 30013 with 3 mm inner radius (PTW, Freiburg, Germany) and two custom built chambers "R1" and "R6" with 1 and 6 mm inner radii respectively were placed at the center of an experimental electromagnet (Schwarzbeck Mess – Elektronik, Germany) 2 cm depth of an in‐house developed 3D printed water phantom. The detector response was measured for a 3 × 10 cm2 field of mono‐energetic protons 221.05 MeV/u for the three chambers, and with an additional proton beam of 157.43 MeV/u for the chamber PTW 30013. The magnetic flux density was varied between 0.1 and 1.0 Tesla in steps of 0.1 Tesla. Results: At both energies, the ionization chamber PTW 30013 showed a non‐linear response as a function of the magnetic field strength, with a decrease of the ionization chamber response of up to 0.27% ± 0.06% (1 SD) at 0.2 Tesla, followed by a smaller effect at higher magnetic field strength. For the chamber R1, the response decreased slightly with the magnetic field strength up to 0.45% ± 0.12% at 1 Tesla, and for the chamber R6, the response decreased up to 0.54% ± 0.13% at 0.1 Tesla, followed by a plateau up to 0.3 Tesla, and a weaker effect at higher magnetic field strength. The dependence of the polarity and recombination correction factor on the magnetic field was ⩽0.1% for the chamber PTW 30013. Conclusions: The magnetic field has a small but significant effect on the chamber response in the low magnetic field region for the chamber PTW 30013 and for R6, and in the high magnetic field region for the chamber R1. Corrections may be necessary for ionization chamber measurements, depending on both the chamber volume and the magnetic flux density. No significant effect of the magnetic field on the polarity and recombination correction factor was detected in this work for the ionization chamber PTW 30013. [ABSTRACT FROM AUTHOR]

Multiple sites within Germany operate human MRI systems with magnetic fields either at 7 Tesla or 9.4 Tesla. In 2013, these sites formed a network to facilitate and harmonize the research being conducted at the different sites and make this technology available to a larger community of researchers and clinicians not only within Germany, but also worldwide. The German Ultrahigh Field Imaging (GUFI) network has defined a strategic goal to establish a 14 Tesla whole-body human MRI system as a national research resource in Germany as the next progression in magnetic field strength. This paper summarizes the history of this initiative, the current status, the motivation for pursuing MR imaging and spectroscopy at such a high magnetic field strength, and the technical and funding challenges involved. It focuses on the scientific and science policy process from the perspective in Germany, and is not intended to be a comprehensive systematic review of the benefits and technical challenges of higher field strengths. [ABSTRACT FROM AUTHOR]

The aim of the present work is to investigate the behavior of two diode-type detectors (PTW microDiamond 60019 and PTW microSilicon 60023) in transverse magnetic field under small field conditions. A formalism based on TRS 483 has been proposed serving as the framework for the application of these high-resolution detectors under these conditions. Measurements were performed at the National Metrology Institute of Germany (PTB, Braunschweig) using a research clinical linear accelerator facility. Quadratic fields corresponding to equivalent square field sizes S between 0.63 and 4.27 cm at the depth of measurement were used. The magnetic field strength was varied up to 1.4 T. Experimental results have been complemented with Monte Carlo simulations up to 1.5 T. Detailed simulations were performed to quantify the small field perturbation effects and the influence of detector components on the dose response. The does response of both detectors decreases by up to 10% at 1.5 T in the largest field size investigated. In S = 0.63 cm, this reduction at 1.5 T is only about half of that observed in field sizes S > 2 cm for both detectors. The results of the Monte Carlo simulations show agreement better than 1% for all investigated conditions. Due to normalization at the machine specific reference field, the resulting small field output correction factors for both detectors in magnetic field are smaller than those in the magnetic field-free case, where correction up to 6.2% at 1.5 T is required for the microSilicon in the smallest field size investigated. The volume-averaging effect of both detectors was shown to be nearly independent of the magnetic field. The influence of the enhanced-density components within the detectors has been identified as the major contributors to their behaviors in magnetic field. Nevertheless, the effect becomes weaker with decreasing field size that may be partially attributed to the deficiency of low energy secondary electrons originated from distant locations in small fields. [ABSTRACT FROM AUTHOR]

This paper presents the simulation results of a multistage depressed collector for a MW-class gyrotron. The energy distribution of spent electrons is obtained by a beam–wave interaction code. By increasing the number of depressed electrodes, the maximum collection efficiency can be increased to 81% with a low percentage of backstreaming 0.04% with regard to a four-stage depressed collector. By considering the secondary electron emission, the effects of different kinds of secondary electrons are simulated in the CST software, which is developed by Computer Simulation Technology Company in Germany. In order to reduce bad effects of secondary electrons, the structure of the fourth depressed electrode has been adjusted to form a slope. The axial length and slant angle of the slope have been optimized. The results indicate that the collection efficiency can exceed 70% and the percentage of backstreaming is less than 1%. Besides, in view of the limited power capacity of the collector wall, a magnetic field sweeping system has been introduced. The maximum power density is reduced to 392 W/cm2, and the deposited length of the electron beam trajectory is 470 mm. [ABSTRACT FROM AUTHOR]

Purpose: Dosimetry of ionizing radiation in the presence of strong magnetic fields is gaining increased relevance in light of advances for MRI‐guided radiation therapy. While the impact of strong magnetic fields on the overall response of ionization chambers has been simulated and measured before, this work investigates the local impact of the magnetic field on dose response in an ion chamber. High‐resolution 1D and 2D response maps have been created for two small clinical thimble ionization chambers, the PinPoint chambers 31006 and 31014 (Physikalisch Technische Werkstaetten Freiburg, Germany). Methods: Working on the Imaging and Medical Beam Line of the Australian Synchrotron an intense kilovoltage radiation beam with very low divergence, collimated to 0.1 mm was used to scan the chambers by moving them on a 2D motion platform. Measured current and beam position were correlated to create the response maps. Small neodymium magnets were used to create a field of about 0.25 T. Chamber axis, magnetic field, and beam direction were perpendicular to each other. Measurements were performed with both orientations of the magnetic field as well as without it. Chamber biases of 5 and 250 V in both polarities were used. Results: The local distribution of the response of small thimble‐type ionization chambers was found to be impacted by a magnetic field. Depending on the orientation of the magnetic field, the chamber response near the stem was either enhanced or reduced with the response near the tip behaving the opposite way. Local changes were in the order of up to 40% compared to measurements without the magnetic field present. Bending of the central electrode was observed for the chamber with the steel electrode. The size of the volume of reduced collection near the guard electrode was impacted by the magnetic field. As the here investigated beam and field parameters differ from those of clinical systems, quantitatively different results would be expected for the latter. However, the gyroradii encountered here were similar to those of a 6–7 MV MRI linac with a 1.5 T magnet. Conclusions: Magnetic fields impact the performance of ionization chambers also on a local level. For practical measurements this might mean a change in the effective point of measurement, in addition to any global corrections. Further knowledge about the local response will help in selecting or constructing optimized chambers for use in magnetic fields. [ABSTRACT FROM AUTHOR]

Conventional ultrasound (US) is the first-line imaging method for abdominal pathologies, but its diagnostic accuracy is operator-dependent, and data storage is usually limited to two-dimensional images. A novel tomographic US system (Curefab CS, Munich, Germany) processes imaging data combined with three-dimensional spatial information using a magnetic field tracking. This enables standardized image presentation in axial planes and a review of the entire examination. The applicability and diagnostic performance of this tomographic US approach was analyzed in an abdominal setting using conventional US as reference. Tomographic US data were successfully compiled in all subjects of a training cohort (20 healthy volunteers) and in 50 patients with abdominal lesions. Image quality (35% and 79% for training and patient cohort respectively) and completeness of organ visualization (45% and 44%) were frequently impaired in tomographic US compared to conventional US. Conventional and tomographic US showed good agreement for measurement of organ sizes in the training cohort (right liver lobe and both kidneys with a median deviation of 5%). In the patient cohort, tomographic US identified 57 of 74 hepatic or renal lesions detected by conventional ultrasound (sensitivity 77%). In conclusion, this study illustrates the diagnostic potential of abdominal tomographic US, but current significant limitations of the tomographic ultrasound device demand further technical improvements before this and comparable approaches can be implemented in clinical practice. [ABSTRACT FROM AUTHOR]

Multiple sites within Germany operate human MRI systems with magnetic fields either at 7 Tesla or 9.4 Tesla. In 2013, these sites formed a network to facilitate and harmonize the research being conducted at the different sites and make this technology available to a larger community of researchers and clinicians not only within Germany, but also worldwide. The German Ultrahigh Field Imaging (GUFI) network has defined a strategic goal to establish a 14 Tesla whole-body human MRI system as a national research resource in Germany as the next progression in magnetic field strength. This paper summarizes the history of this initiative, the current status, the motivation for pursuing MR imaging and spectroscopy at such a high magnetic field strength, and the technical and funding challenges involved. It focuses on the scientific and science policy process from the perspective in Germany, and is not intended to be a comprehensive systematic review of the benefits and technical challenges of higher field strengths., (© 2023. The Author(s).)

The article offers information on the topics tackled during a conference in Hohenkammer, Bavaria, Germany on October 20-22, 2016. Topics include the influence of magnetic field stimulation and microgravity on the vestibular system, honoring Marianne Dieterich in recognition of her outstanding scientific and clinical contributions to the field, and her contributions to the clinical classification of vestibular disorders.

Magnetic properties of hydrocarbon (HC) containing soils and sediments from two sites (Site A and B) of the former oil-field Hänigsen were analyzed in order to determine whether magnetic methods can be employed to delineate HC contamination of soils and sediments. Magnetic parameters such as magnetic susceptibility and induced isothermal remanent magnetizations, as well as soil and sediment properties such as pH, iron content and water content, HC content and most probable number counts of iron-metabolizing microorganisms were determined. The magnetic concentration-dependent parameters for HC contaminated samples were 25 times higher in soils from Site A than in sediment samples from Site B. However, at Site B the magnetic susceptibility was still four times higher in comparison to lithologically similar non-contaminated sediment samples from a third Site C. Newly formed magnetite containing mainly single domain particles was responsible for the magnetic enhancement, whereas superparamagnetic grains represented only a minor component. Site A had an acidic pH compared to neutral pH at Site B, and a higher crystalline and bioavailable total iron content. Nevertheless, Site B samples contained significant numbers of both iron(II)-oxidizing and iron(III)-reducing microorganisms indicating that microbial iron cycling might have taken place at this site and potentially played a role for iron mineral transformation, including magnetite (trans)formation. The content of total non-polar hydrocarbons (TNPH) at Site A was one order of magnitude higher than at Site B. Only at Site A magnetic susceptibility correlated well with TNPH. Our results demonstrate that HC contaminated samples had an enhanced magnetite content compared to non-contaminated soils and sediments. Therefore, magnetic methods may provide a quick and cost-effective way to assess HC contamination in soils and sediments. However, more field sites and laboratory investigations are needed to reveal the complex nature of the processes involved. [ABSTRACT FROM AUTHOR]

Magnetically impelled arc butt (MIAB) welding is a solid phase pressure welding process similar to flash-butt welding, but it uses a magnetic field to rapidly spin the arc. The spinning arc provides a more consistent interior and exterior weld flash than typically seen on the flash-butt upset areas. MIAB welding process is presently being employed for welding tubular sections in automobile industries in various parts of United Kingdom and Germany. However, there are no details reported in available literatures on application of MIAB welding process for pressure parts. Hence, in this study, a pivotal attempt is being made to employ MIAB welding process to weld carbon steel tubes (51 mm and 44 mm outer diameter) and (5-6 mm thick) in economizer coils of pressure vessel. Several trials are conducted to create an optimal parameter window for MIAB welding process by varying the different input parameters. Further, mechanical testing and metallurgical characterization are carried out on the MIAB-welded specimen to evaluate its strength and to assess the weld integrity. The results of the experiment emphasized that the MIAB-welded joints exhibited high strength and good weld integrity. [ABSTRACT FROM PUBLISHER]

SUMMARY We carried out palaeointensity experiments on 45 samples collected throughout the ca. 15 Ma Ries crater (Germany) to test whether meteorite impacts can influence the geodynamo. A Thellier-Thellier procedure with alteration, tail and additivity checks yields a weighted average palaeointensity of 19.1 ± 1.1 μT from 15 samples that pass stringent data selection criteria. The corresponding virtual dipole moment of 3.2 ± 0.2 × 1022 Am2 is relatively low, but indistinguishable from the global palaeointensity database between 20 and 10 Ma. Our results suggest that either the energy released during the Ries meteorite impact event was too low to affect the geodynamo, the Ries impact lithologies cooled too fast to record any effect, or the time averaged by the impact lithologies was long enough to record secular variation, but that the geodynamo was remarkably stable over that time. [ABSTRACT FROM AUTHOR]

The toroidal field model coil (TFMC) was extensively tested in 2001–2002, in the TOSKA facility at the Karlsruhe Institute of Technology, Germany, up to a maximum transport current of 80 kA and a peak magnetic field of \sim10 T. Here, we apply the 4C code, which was developed for the analysis of thermal-hydraulic transients in superconducting magnets, including winding, structures, and cryogenic circuit, to the analysis of the TFMC safety discharge from 80 kA. The code is able to reproduce the main experimental features, despite the limitations due to no more fully available information about the details of the cryogenic circuit, which play here a much more important role than at lower currents. [ABSTRACT FROM PUBLISHER]

SUMMARY The North German Conductivity Anomaly was detected already in the early years of electromagnetic deep sounding. It refers to the reversal of induction arrows (as a graphical representation of the tipper transfer function, the ratio of vertical to horizontal magnetic field variations) at the northern and southern margins of the North German Basin. In spite of the many experiments carried out so far, its origin has remained ambiguous; explanations encompass a deep-crustal or even mantle source as well as the simple response to deepening of sedimentary sequences in the centre of the basin. Here, we report on modelling of new long-period magnetotelluric data collected along two profiles in NE Germany and S Sweden, with one transect crossing the Sorgenfrei-Tornquist Zone as the main boundary between Precambrian Baltica and the Palaeozoic belts of central Europe. With the exception of a few sites probably influenced by 3-D salt domes, the data allow a 2-D analysis. Resolution is reduced for large depths due to a well-conducting, saline aquifer, extending across the entire basin. The main result is that the reversal of induction arrows can largely be explained by the resistivity contrast between crystalline basement and sedimentary basin fill. Beneath Rügen island, a southward dipping conductor is interpreted to reflect an alum shale layer in Middle Cambrian-Lower Ordovician sediments. Beneath the southern basin, a moderately conductive upper mantle is modelled (although not very well resolved) which may reflect the thinning of the lithosphere as implied by seismic tomography. As the main anomalously inductive effect is primarily explained by the basin edges and numerous other anomalies exist inside the basin, we suggest not using the term 'North German Conductivity Anomaly' any longer. [ABSTRACT FROM AUTHOR]

Anomalies of the Earth's total magnetic field reveal important information about crustal structures. For the first time, a homogenous map of anomalies of the Earth's total magnetic field for the whole of Germany is available. The map is based on 50 shipborne, airborne and ground surveys, which were conducted between 1960 and 1990 and complemented by 17 new surveys after German reunification. The map, with a grid spacing of 100 m, consistently images the entire anomaly pattern in Germany at an altitude of 1000 m a.s.l. related to the DGRF 1980, epoch 1980.0. Because of these reference parameters and consideration of new data, the resolution of this map is higher than any previously published map. The homogenized and complete data set enables the distinction of different magnetic anomalies and - by observing their vector character - the identification of magnetic sources from different stages of the geological history. Since the map images the superposition of magnetic source anomalies from different depths and therefore combines long- and short-wavelength spectrums within one data set, it offers new insights into crustal structures. Not only regional tectonic units, such as the Variscan terranes in south and central Germany, or the extent of old Scandinavian crust under North Germany, as a relict of the collision between Baltica and Avalonia are imaged, but also details of local structures such as the volcanic areas of the Vogelsberg and the Eifel region. Therefore, the new data set can be used for work on modern topics in geosciences that cover both fundamental and applied research - for example, the structural and petrophysical characterization of the crust, its rheology and geodynamic evolution, or even hydrocarbon exploration. The gridded data is available as an electronic supplement to this paper. [ABSTRACT FROM AUTHOR]

The Super-FRS (Super FRagment Separator) is a part of FAIR (Facility for Antiproton and Ion Research), which will be constructed at GSI, Germany by 17 countries. The Super-FRS comprises 24 superferric dipole magnets. The 2D and 3D magnetic field simulations of the prototype magnet are described in this paper. A passive trim slot and four chamfered removable poles are used to satisfy the required field homogeneity which is better than ±3 x 10-4 at 1.6 T, 0.8 T and 0.16 T in a wide elliptical useable aperture of 380 mm 140 mm. Measurement results at various field levels are shown in this paper as well. It can be seen from the comparison of calculation and measurement results that the magnetic designs of the magnet fulfils the requirements. [ABSTRACT FROM AUTHOR]

The Forschungszentrum Jülich is responsible for the complete design and the construction of the High-Energy Storage Ring HESR, at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. This includes the layout and provision of all magnets where the dipole, quadrupole and sextupole magnets are the most important. All magnets will be iron-dominated and normally conductive. The distance between the magnets is small due to the restricted space in the tunnel. In contrast to isolated magnets, differences are expected for the effective magnetic length as well as the integrated higher-order multipole contributions. In this publication, the results of magnetic-field calculations are presented that assess the magnetic interaction of neighboring magnets. [ABSTRACT FROM AUTHOR]

Very high pulsed magnetic fields can be generated more economically using a system of multiple coils, with a high-energy, limited-power pulse generator providing the background field for a smaller inner coil, energized in its turn, but for a much shorter pulse duration, with a very high-power, limited-energy generator. Because of the increased number of parameters in the design of multi-coils, systematic insight into their mutual dependence is helpful in order to converge to an optimized design. In this paper we will discuss strategies to determine the optimum choice for the design of inner- and outer-coil and how to optimize their design in relation to the type of pulse generator used. In particular, we will consider energy-limited capacitor banks and power-limited supplies. The approach will use scaling arguments and modeling tools as the ‘Pulsed Magnet Design Software’ (PMDS) package, developed at the Katholieke Universiteit Leuven and Huazhong University of Science and Technology. Optimization of coil systems is demonstrated with the example of the successful 87 T pulsed dual-coil system in Dresden. [ABSTRACT FROM AUTHOR]

Abstract: Neutrons are highly sensitive to magnetic fields because of their intrinsic magnetic moment. At the same time, their zero net electrical charge allows them to penetrate thick layers of matter. In combination with standard radiographic and tomographic imaging techniques, these properties have been exploited to visualize magnetic fields in free space and within the bulk of solid, massive, opaque samples. In this paper, the basic principle of this new technique and its realization at the CONRAD instrument at the Helmholtz Centre Berlin (formerly Hahn-Meitner Institute Berlin) are explained. Two application examples will be given: the visualization of the magnetic field around a permanent magnet and the investigation of the displacement of the current density from the core of a conductor to the surface (the skin effect). [Copyright &y& Elsevier]

Abstract: The main magnetic field of Wendelstein 7-X fusion experiment (W7-X) at Max-Planck-Institut für Plasmaphysik Greifswald, Germany will be provided by 50 non-planar coils and supported by 20 planar coils. The non-planar coils were delivered by a consortium (CON) consisting of Babcock Noell GmbH Germany (BNG) and ASG Superconductors S.p.A. Italy (ASG). The coil production ended with the delivery of the last non-planar coil in March 2008 at the manufacturing branch of BNG in Zeitz, Germany. The construction of the coils was characterised by design changes, many rework actions and resulting time delays. Due to these numerous adjustments and changes a continuous improvement process was needed. This paper will give an overview about the transition of the non-planar coils from the acceptance tests at the manufacturer site to the beginning of the assembly at IPP. Furthermore this report will highlight technical interfaces in the period of transition. [Copyright &y& Elsevier]

Abstract: Wendelstein 7-X, currently under construction at the Max-Planck-Institut für Plasmaphysik in Greifswald, Germany, is a modular advanced stellarator, combining the modular coil concept with optimised properties of the plasma. The magnet system of the machine consists of 50 non-planar and 20 planar superconducting coils which are arranged in five identical modules, forming a toroidal five-fold symmetric system. The majority of operational magnetic configurations will have rotational transform ι/2π =1 at the boundary. Such configurations are very sensitive to symmetry breaking perturbations, which are the consequence of imprecisely manufactured coils or assembly errors. To date, all 70 coils have been fabricated, and the first two half-modules of the machine have been assembled. The comparative analysis of manufactured winding packs and estimates of the corresponding level of magnetic field perturbation are presented. The dependency of the error fields on the coil assembly sequence is considered, as well as the impact of the first assembly errors. The influence of different construction uncertainties is discussed, and measures to minimise the magnetic field perturbation are suggested. [Copyright &y& Elsevier]

Secular change of the earth's magnetic field is a comparatively regional phenomenon and that does not proceed in a regular manner across the earth. This gives rise to regions where the magnetic field changes more rapidly than elsewhere, like for instance southern Africa. As part of a cooperative project between Germany and South Africa, called Inkaba ye Africa, the COMPASS (COmprehensive Magnetic Processes under the African Southern Sub-continent) program aims to study the regional geomagnetic field and in particular its evolutionary behaviour. In addition to a rapid decrease of the geomagnetic field in this region, as evidenced by the 20% decrease observed at Hermanus, the orientation of the geomagnetic field in southern Africa is also changing rapidly. In the north-western part of southern Africa the declination of the magnetic field is propagating eastward (Tsumeb) and in the south-eastern part it propagates westward (Hermanus and Hartebeesthoek). This results in an overall increase of the spatial gradient over the subcontinent with time. During 2005, a joint field survey campaign was conducted by the Hermanus Magnetic Observatory (HMO) and the GeoForschungsZentrum (GFZ) in South Africa, Namibia and Botswana in order to characterize the time variation of different components of the geomagnetic field. Rest, Its obtained from this field survey, together with information obtained from the previous field survey during 2004 at 8 field stations, in addition to such data from the three continuous recording magnetic observatories in southern Africa at Hermanus, Hartebeesthoek and Tsumeb, are used to model the geomagnetic field time variation for 2004 to 2005, using a polynomial approach. [ABSTRACT FROM AUTHOR]

Geomagnetic repeat station data of Germany from 1964 to present have been studied to determine their accuracy and crustal biases. Like the data from geomagnetic observatories, repeat station data contain contributions from the regional and local crustal field, but their spatial density is by far not high enough to resolve such anomalies. Knowing this crustal bias, therefore, is important in using repeat station data to map or model the main field. To confirm the results obtained by using a global geomagnetic field model we constructed regional lithospheric field models using additional information from satellite and aeromagnetic data. The compatibility of the different data types is good and we present vectorial anomaly maps for Germany with a spatial resolution of approximately 37 km, which could be useful for future geological interpretation of magnetic anomalies. The anomalies contributing to the repeat station bias, however, can be of smaller scale and their amplitudes range up to absolute values of 177 nT in the north ( X), 106 nT in the east ( Y) and 176 nT in the vertical ( Z) component. Average uncertainty estimates in the order of 5, 8 and 5 nT in X, Y and Z, respectively, are obtained from comparisons to a global model. The estimates, however, vary a lot between stations and components. The uncertainties should mostly result from measurement errors, insufficient elimination of external field contributions or relocations of stations which had been regarded as insignificant. There might also be a small contribution from insufficient description of secular variation in the global model used. [ABSTRACT FROM AUTHOR]

Fast cycling superferric magnets are planned for use in the new International Accelerator Facility for Antiprotons and Ion Research (FAIR) at GSI, Darmstadt. The efficiency of this magnet is basically defined by the AC loss at liquid helium temperatures in the construction elements of the dipoles and quadrupoles (iron yoke, coil, beam pipe restraints and suspension). A detailed knowledge of the 3D magnetic field, the eddy current distributions and their transient behavior is necessary to minimize the hysteresis and the eddy current losses through the use of an appropriate design. Methodical problems are considered for finite element calculations (ANSYS) of eddy currents in a laminated iron yoke. The results for window-frame dipoles and quadrupoles of the Nuclotron type are given. We present the influence of nonlinear and anisotropic magnetic and electrical properties of laminated steel and of bulk restraint elements. [ABSTRACT FROM AUTHOR]

FAIR, a new international accelerator complex is now being developed by GSI (Darmstadt, Germany). The synchrotron SIS100 is a part of this complex and will be equipped exclusively with fast-cycling superferric magnets. The magnet system of this accelerator includes 168 identical quadrupoles with a maximum gradient of 33.4 Tim in an elliptical useable aperture of 120 mm × 65 mm. An important requirement of the quadrupole design is a field gradient uniformity better than ±0.06% for field gradient variation range of 3 T/m-3.3 Tim. This goal is achieved by introducing slots in the central part of the magnet poles, creating the effect of artificial saturation. Simultaneously, these slots reduce the eddy currents in the yoke, induced by the current ramp in the magnet coil. This is important because the whole magnet will be operated near 4.2 K, so the power loss in the yoke should be minimized. Additionally, the shape of the quadrupole pole ends was optimized to provide the necessary integral field quality. [ABSTRACT FROM AUTHOR]

An important part of FAIR (Facility for Antiproton and Ion Research), being developed at GSI, Darmstadt, Germany, is the fast-ramping heavy ion synchrotron SIS 300. The main elements of the SIS 300 magnetic system are 6 T, 2.6 m long superconducting dipoles, to guide charged particle beams on a path with a 50 m curvature radius. A model superconducting dipole, manufactured for the UNK project, was chosen to study the influence of bending on the magnet characteristics. The straight collared coil of this model magnet was tested, then bent with a 50 m curvature radius, and then retested. The main measured and calculated characteristics of the coil for both tests are presented. Test results showed similar characteristics, both in training and in ramp rate dependence, as well as in field quality of the straight and bent coils. There is a good agreement between measured and calculated results of the completed study. [ABSTRACT FROM AUTHOR]

Focuses on the high field magnet facilities and projects at the Forschungszentrum Karlsruhe in Karlsruhe, Germany. Facility setups based on advanced superconducting magnets; Magnet system of JUMBO facility; Measurements of magnetic fields in HOMER I amd II; Magnets developed at MTA.

This paper presents a MATLAB based program, including an easy-to-use graphical interface, developed to estimate 3D geometry of magnetic basement interfaces from respective gridded magnetic anomalies by a rapid iterative procedure. The developed code uses an algorithm based on a relationship between the Fourier transforms of the magnetic data and the interface topography. Given the average depth to the magnetic interface and parameters related to the magnetization, the iterative procedure built up in the frequency domain results with accurate depth estimates in a very short computing time. The program is capable of handling large data sets. The convergence in the iterative process is improved by incorporating a high-cut filtering. The iterations stop when either the RMS error between two successive approximations at any step of the iteration has increased relative to the previous step or when the RMS is below a predefined threshold value, or after a specified maximum iterations number. Settings and updating of the input parameters as well as displaying and exporting the interpretation outputs can easily be managed with the interactive control skills supported by the graphical user interface (GUI) of the MagB_inv code. Applicability and efficacy of the algorithm are illustrated on synthetic data from three 3D interface models, the respective inverted depths match the actual depths even in the presence of noise. As a practical example, the algorithm was also applied to observed anomalies of the total magnetic field from NW-Germany. The calculated magnetic basement interface from the real data application is in good agreement with the previously published configurations of the basement of this study area. • We developed a MATLAB program to invert gridded magnetic anomalies. • The iterative procedure is built up in the frequency domain. • The algorithm is capable in handling large data sets. • The code was proven useful in determining the magnetic basement structure. [ABSTRACT FROM AUTHOR]

We observed a moderate but statistically non-significant association between magnetic fields (MF) and childhood leukaemia. This is the first such study to cover residential exposure to 16.7 Hz (railway frequency) MF though based on few exposed subjects. Our study does not exclude a small excess risk, but the attributable risk must be very low. It is reassuring that neglecting 16.7 Hz MF in childhood cancer studies appears to have little effect on findings. [ABSTRACT FROM AUTHOR]

The LIBELLE experiment performed at the experimental storage ring at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany, has successfully determined the ground state hyperfine (HFS) splittings in hydrogen-like () and lithium-like () bismuth. The study of HFS transitions in highly charged ions enables precision tests of QED in extreme electric and magnetic fields otherwise not attainable in laboratory experiments. Besides the transition wavelengths the time-resolved detection of fluorescence photons following the excitation of the ions by a pulsed laser system also allows the extraction of lifetimes of the upper HFS levels and g-factors of the bound 1s and 2s electrons for both charge states. While the lifetime of the upper HFS state in has already been measured in earlier experiments, an experimental value for lifetime of this state in is reported for the first time in this work. [ABSTRACT FROM AUTHOR]

The article discusses the highlights of the 9th International Conference on Research in High Magnetic Fields (RHMF) held in Dresden, Germany from July 22 to 25, 2009. Participants in the event came from various countries, including China, Japan and the U.S. Papers presented at the conference focused on such topics as magnetism, superconductivity and semiconductor physics.

The article focuses on the research conducted in 2007 by theoretical physicists from California and experimental physicists in Germany which predicted that semiconductor sandwiches with thin layers of mercury telluride in the middle will exhibit quantum spin Hall effect (QSHE). The author inferred that QSHE is an unusual behavior of electrons when placed in an electric or magnetic field. The author averred that performing QSHE at room temperature could lead to the development of new low-power spintronic computing devices that manipulate electrons by both charge and spin.

The twenty-three papers from this special issue were presented at the 3rd International Conference on Microwave Magnetics (ICMM) that was held 26-29 August 2012, in Kaiserlautern, Germany. [ABSTRACT FROM AUTHOR]

An endstation for pump-probe small-angle X-ray scattering (SAXS) experiments at the free-electron laser in Hamburg (FLASH) is presented. The endstation houses a solid-state absorber, optical incoupling for pump-probe experiments, time zero measurement, sample chamber, and detection unit. It can be used at all FLASH beamlines in the whole photon energy range offered by FLASH. The capabilities of the setup are demonstrated by showing the results of resonant magnetic SAXS measurements on cobalt-platinum multilayer samples grown on freestanding Si3N4 membranes and pump-laser-induced grid structures in multilayer samples. [ABSTRACT FROM AUTHOR]

The article offers information on a workshop on stochasticity in fusion plasmas held in Jülich, Germany from April 11-14, 2011. The workshop featured several sessions including plasma response models, application of resonant magnetic perturbation and transportation of energy in stochastic magnetic fields. It presents a table which shows the codes to be used for identifying the response of plasma to external magnetic perturbation fields.

The article presents an analysis of the nonaxial dipole (NAD) field at Earth's surface to explain magnetic source separation in Earth's outer core. It mentions that time-averaged NAD field could be used as proxy for the modern-day NAD field. It shows the effect of NAD field secular variation on widely separated sites of West Eifel in Germany and Tahiti in French Polynesia. It notes that modern-day NAD field structure and behavior tend to explain the paleomagnetic findings in both sites. It suggests that there are two independent field sources in the planet wherein, the first is generated deep within the outer core and the other is generated in the shallow core.

The article focuses on the research regarding the person's gene variant by the group of neuroscientists in Germany. The study associated with the combination of brain imaging including the project that allows the participants to select symbols on the computer screen. However, the functional magnetic resonance imaging (fMRI) will grant the player to perform a learning task by looking the three pairs of Chinese ideograms. In addition, Michael Frank of the University of Arizona said that the investigation reveals different responses to negative reaction

An interview with Alexander Schwarz who built a microscope, along with his colleagues, to scan non-conducting materials, at the University of Hamburg, Germany, is presented. When asked about the uniqueness of the microscope, he referred to the use of magnetic field to increase exchange forces. Schwarz explained the difficulties in building the microscope. He believes that building any electronic component without non-conducting materials is impossible.

The article focuses on the use of nuclear magnetic resonance (NMR) spectroscopy in forests. Stephan Appelt, a scientist, and his colleagues took their homemade NMR spectrometers into a forest in Germany. The new instrument proved to be more simple and useful than the previous earth's field NMR spectrometers. The earth's magnetic field is very weak, and cannot polarize magnetic spins for NMR. So, in order to produce a measurable signal, spins must be prepolarized. Appelt used a Halbach magnet to prepolarize the nuclear spins. The main limitation of earth's field spectroscopy is the presence of stray magnetic fields. Appelt and colleagues decided to perform their experiments in a forest, because of the presence of destructive stray magnetic fields in human environments. In laboratories, there is a need to shield against the stray magnetic fields, which is not there in the case of forests. In earth's field NMR, lithium is difficult to study because of its low signal. The researchers detected lithium for the first time by the earth's field NMR. They proposed that due to the high sensitivity of lithium's relaxation time to temperature and concentration, earth's field NMR could be used to generate a map of neuron channels in the brain.

We have proposed to build a 100 T/10 ms, 70 T/100 ms, 60 T/I s pulsed field user facility with a 50 MJ capacitor bank at the Forschungszentrum Rossendorf near Dresden. This would provide the appealing possibility to have access to Zeeman energies in the energy range of the infrared free-electron-lasers (5 µm to 150 µm; 2 ps; cw; >10 W) now under construction at the radiation source ELBE (superconducting electron linear accelerator; 40 MeV; 1 mA; 2 ps; cw) in Rossendorf. The work is accompanied by computer simulations of the planned coil systems, of the power supply, and by the development of high-strength conductors aiming at a tensile strength of about 1.5 GPa at δ = δ Cu/2 (microcomposite CuAg alloys and Cu-steel macro compounds). With a view of gaining experience in the construction and operation of pulsed magnets, a pilot pulsed field laboratory was established at the Institute of Solid State and Materials Research Dresden (IFW Dresden). The laboratory includes short pulse magnets with peak field up to 60 T in a 24 mm bore and a rise time of about 10 ms (coil from NHMFL, Tallahassee), and a 40 T long pulse magnet with 24 mm bore and rise time of about 80 ms (coil from METIS, Leuven). The repetition rate of 20 min between pulses is limited by the cooling time of the coils. The coils are energized by a 1 MJ, 10 kV capacitor bank with some special features. With this set-up measurements of magnetization and magnetotransport on 4f-electron systems, for example RECu2, have been carried out in the temperature range of 1.5 to 300 K and at fields up to 52 T using high precision pick-up coils. [ABSTRACT FROM AUTHOR]

The mechanisms by which migratory birds achieve their often spectacular navigational performance are still largely unclear, but perception of cues from the Earth's magnetic field is thought to play a role. Birds that possess migratory experience can use map-based navigation, which may involve a receptor that uses ferrimagnetic material for detecting gradients in the magnetic field. Such a mechanism can be experimentally disrupted by applying a strong magnetic pulse that re-magnetizes ferrimagnetic materials. In captivity, this treatment indeed affected bearings of adult but not of naive juvenile birds. However, field studies, which expose birds to various navigational cues, yielded mixed results. Supportive studies were difficult to interpret because they were conducted in spring when all age groups navigate back to breeding areas. The present study, therefore, applied a magnetic pulse treatment in autumn to naturally migrating, radio-tagged European robins. We found that, although overall bearings were seasonally correct, orientation of adult but not juvenile robins was compromised by a pulse. Pulsed adults that departed within 10 days of treatment failed to show significant orientation and deviated more from mean migration direction than adult controls and juveniles. Thus, our data give field-based support for a possible ferrimagnetic map-sense during bird migration.