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On a Wendelstein 7-X (W7-X), an alkali metal beam (AMB) diagnostic system was installed in order to measure the plasma edge electron density profiles and turbulence transport. A sodium beam was injected in the plasma, and the light emission was observed by an optical system. During the last operation phase, OP1.2b campaign trial spectral measurements were performed with a dedicated optical branch. The results showed the emergence of potential CX lines in the light spectra during sodium injection. The lines were identified as Carbon III, which were the dominant lines observed by other diagnostics at the edge plasma. Based on these results, an additional dedicated optical system was developed and installed in 2021 for the upcoming operational phase, OP2. The optics were designed for multiple purposes: spectral measurements for the AMB system and for a He/Ne gas jet. The system was designed to allow implementation of further diagnostics on this port later (e.g., coherence imaging system). The details of the implementation of the design requirements and the main challenges of the manufacturing process and installation are discussed in this paper.

The paper reports for the first time the heat and particle exhaust at the plasma boundary through various edge diagnostics for the high-performance plasma obtained after pellet injection on Wendelstein 7-X. The plasma density at the edge is found to be reduced by a factor of 2 in the high-performance phase, supporting the previously reported density peaking at the plasma centre. The plasma beta effect on the magnetic topology is reflected by the appearance of the second strike line, which is well understood with simulation. However, during the rapid decay phase of the enhanced confinement, a transient localized heat flow of up to 16 MW m ^−2 is observed at the leading edge of a poorly cooled divertor component, which has not been understood but raises concerns about machine safety.

In the first divertor campaign in Wendelstein 7-X (W7-X), unexpected significant heat loads were observed at particular plasma-facing components (e.g. baffle tiles and middle divertor part) which were not designed to receive high heat flux. In a prior investigation, it was concluded that the previous diffusive field line tracing (DFLT) model used for divertor design in W7-X cannot reproduce these loads, due to the missing physics in simulating the heat transport in the shaded flux tubes. To tackle this issue, two new efficient codes (DFLT_rev and EMC3-Lite) are introduced and validated against various experimental heat distributions in different magnetic configurations. The new tungsten baffle tiles have been designed with these codes and mounted in the machine, aiming for mitigated heat loads in the upcoming campaign.

In diesem Beitrag gehen wir am Beispiel der dokumentarischen Methode darauf ein, wie eine rekonstruktive Forschungsmethodologie für forschungspraktisch unerfahrene Menschen durch Erklärvideos in verständlicher Sprache didaktisch anschlussfähig gemacht werden kann. Hintergrund dieses Vorschlags ist unsere Erfahrung, dass für Personen ohne konkrete Forschungserfahrung überhaupt erst einmal eine Annäherung an rekonstruktives Denken als genuine Forschungslogik herzustellen ist, um dann z.B. forschendes Lernen mit sinnverstehenden Methoden oder die Partizipation von Co-Forschenden in rekonstruktiven Projekten zu ermöglichen. Ausgangspunkt für die Erstellung unserer Videos war ein aktuelles Forschungsprojekt zu inklusiver Erwachsenenbildung. Als rekonstruktiv Forschende in einem teilweise partizipativ angelegten Verbundforschungsprojekt mussten wir unser methodisches Vorgehen so aufbereiten, dass alle Mitglieder einer partizipativen Forschungsgruppe das Zustandekommen unserer Ergebnisse substanziell nachvollziehen konnten. Auf dieser Basis reflektieren wir das grundsätzliche Verhältnis von rekonstruktiver Forschung als genuine Forschungsmethodologie und partizipativer Forschung als praktischem Forschungsstil. Dabei begründen wir am Beispiel der dokumentarischen Methode unsere Position, dass Forschende, die mit rekonstruktiven Ansätzen arbeiten, auf der Erkenntnisebene von einer stärkeren partizipativen Ausrichtung profitieren können und sich dem auch aus forschungsethischen Gründen nicht verschließen sollten.

Die praxeologisch-rekonstruktiv ausgerichtete Erforschung des Bildungskontextes inklusiver Hochschule steht, anders als dies für den Bereich der rekonstruktiven Schul- und Unterrichts­forschung gesagt werden kann, noch am Anfang. Das in diesem Artikel vorgestellte Verbundprojekt erweitert den Blick auf Inklusionsbedingungen auf der Ebene der Lehre von Bildungsfachkräften. Damit löst es sich von einer sonst dominierenden Adressat*innenlogik, welche die Inklusionsfrage fast ausschließlich für die Lernenden stellt. Die im Projekt durchgeführten Videografien und Gruppendiskussionen wurden auf Grundlage der Dokumen­tarischen Methode analysiert. Der vorliegende Artikel geht auf das Forschungsdesign und erste Forschungsergebnisse ein. Hierbei spielt das rekonstruierte Anerkennungserleben der Bildungsfachkräfte eine zentrale Rolle. Abstract Compared with the fast growing amount of reconstructive studies on inclusion in school research, reconstructive studies on inclusive teaching at universities are rare. First results of a reconstructive research project about inclusive teaching in higher and adult education widens the perspective on conditions of inclusion: It focusses on the teaching-praxis of so called ‘Bildungsfachkräfte’, people with learning disabilities who accomplished a training program lasting three years to qualify for teaching in various academic settings. Our analysis considers the layer of inclusive teaching instead of conditions of inclusive learning. The videographies and group discussions conducted in the project are analysed on the basis of the documentary method. The experiences of recognition will be analysed empirically as a pattern of orientation among the so called ‘Bildungsfachkräfte’ which guides their teaching approach towards inclusion.

The control of rotational transform in Wendelstein 7-X (W7-X) is key to both the island divertor operation and safety of plasma facing components. The island divertor concept in W7-X relies on an edge flux surface with rotational transform of resonating with an intrinsic n/m  =  5/5 resonance to form a five lobed island chain. This island chain intersects with divertor plates to give rise to the island divertor. Changes in the relative position of the rational surface and the divertor plates can result in changes in divertor performance, thus the control of the rotational transform is essential to operation of the W7-X device. During the first divertor campaign electromagnetic loads resulted in elastic deformations of the shaped modular stellarator coils. Such deformations made these coils more planar, reducing the vacuum rotational transform, subsequently shifting the resonance outward. Unintended plasma wall interactions provided the first clear evidence of this effect during plasma operation. Flux surface measurements were utilized to estimate the correct level of current in the planar coils for correction of , and found to be around  ∼. Scans of the planar coil current for iota correction were performed during plasma operation. These measurements suggest planar coil currents between  −250 and  ∼ would place the strike lines at the designed distance from the pumping gaps. Divertor Langmuir and upstream probe measurements confirm these estimates along with measurements of divertor neutral gas pressure. [ABSTRACT FROM AUTHOR]

The paper presents experimental observations and simulations for the effects of toroidal plasma current on divertor power depositions on W7-X. With increasing toroidal current accompanying changes in the island geometry result in a sweep of the strike line and a redistribution of the heat flux footprints. Good agreement between experiments, which partly used electron cyclotron current drive to generate an additional toroidal current contribution, and modelling using field line tracing in vacuum magnetic fields including an ad-hoc toroidal current on the magnetic axis is found for both standard and low-iota magnetic configurations. [ABSTRACT FROM AUTHOR]

The role of error fields in stellarators is explored in this work through simulations of, and experiments performed on, the Wendelstein 7-X (W7-X) stellarator. Previous experimental results, based on limiter plasmas in W7-X, suggest that error fields are small in the experiment based on limiter plasmas. In this work, we document results from the first divertor campaign on W7-X with a focus on error fields resonant with the edge island divertor structure. Measurements obtained using divertor thermocouples corroborate earlier limiter results that the error fields are small and correctable, requiring only 5% of the total rated current of the trim coil system. The effect of these error fields on magnetic geometry and topology are investigated using the flux surface measurement technique. The resulting divertor thermal load asymmetry is modeled via field line diffusion and compared to experimental data. [ABSTRACT FROM AUTHOR]

An exploration of the interdisciplinary field of intercultural communication reveals both very inspiring thoughts and instruments to analyze culture in human interaction, and a confusing diversity of methods and arguments to deal with. In this article a "conceptual metaphor" (LAKOFF & JOHNSON, 1980) of exploring unknown territories and spaces is proposed for establishing a heuristic frame to maneuver through a rapidly expanding "galaxy" of research on intercultural communication. The aim is to provide a general framework to assess the methodological coherence of empirical studies on intercultural communication, as well as their relative position in the wider field of qualitative social research methodologies. Three dimensions will be discussed: 1) The theoretical question of the underlying cultural concept of a research project, 2) the methodical question of the basic research design and modes of analysis, and 3) the question of generalizations drawn from the empirical findings. These dimensions constitute what we call a methodological galaxy in which current trends and developments of the field of intercultural communication can be located and traced. The suggested framework may serve as a guiding "compass," using a set of "etic" parameters for navigation while respecting the "emic" nature of qualitative approaches. URN: urn:nbn:de:0114-fqs0901520

This article introduces to the thematic scope and the articles of this special issue and it explains some important terminological distinctions of the intercultural research field. The overall aim of this issue is to explore the manifold ways to apply and to reflect upon qualitative research methods in the context of intercultural communication. This implies both a discussion of genuine characteristics of intercultural qualitative research as well as attempts to identify common features and linkages of this special area with more general interpretative research traditions under the "umbrella" of qualitative social research. URN: urn:nbn:de:0114-fqs0901342

The measurement and correction of error fields in Wendelstein 7-X (W7-X) is critical to long pulse high beta operation, as small error fields may cause overloading of divertor plates in some configurations. Accordingly, as part of a broad collaborative effort, the detection and correction of error fields on the W7-X experiment has been performed using the trim coil system in conjunction with the flux surface mapping diagnostic and high resolution infrared camera. In the early commissioning phase of the experiment, the trim coils were used to open an n/m  =  1/2 island chain in a specially designed magnetic configuration. The flux surfacing mapping diagnostic was then able to directly image the magnetic topology of the experiment, allowing the inference of a small  ∼4 cm intrinsic island chain. The suspected main sources of the error field, slight misalignment and deformations of the superconducting coils, are then confirmed through experimental modeling using the detailed measurements of the coil positions. Observations of the limiters temperatures in module 5 shows a clear dependence of the limiter heat flux pattern as the perturbing fields are rotated. Plasma experiments without applied correcting fields show a significant asymmetry in neutral pressure (centered in module 4) and light emission (visible, H-alpha, CII, and CIII). Such pressure asymmetry is associated with plasma-wall (limiter) interaction asymmetries between the modules. Application of trim coil fields with n  =  1 waveform correct the imbalance. Confirmation of the error fields allows the assessment of magnetic fields which resonate with the n/m  =  5/5 island chain. [ABSTRACT FROM AUTHOR]

Much of the theoretical and empirical research on intercultural communication in Germany emerges at the disciplinary edges of Linguistics, Sociology, Anthropology, Psychology or Educational Studies. The book "Kultur(en) im Gespräch"—translated roughly as Culture(s) in Conversation—edited by Helga KOTTHOFF, covers a wide range of theoretical and methodical approaches to the analysis of intercultural conversation and discourse. Most of the contributions refer to concepts of Socio-Linguistics and Linguistic Anthropology. The focus on the reflection of applying qualitative research methods used in the scope of intercultural conversation and discourse analysis let this book become a source of inspiration for the own research practice. URN: urn:nbn:de:0114-fqs030345

Error fields have been detected and quantified using the flux surface mapping diagnostic system on Wendelstein 7-X (W7-X). A low-field ‘’ magnetic configuration (), sensitive to error fields, was developed in order to detect their presence using the flux surface mapping diagnostic. In this configuration, a vacuum flux surface with rotational transform of n/m  =  1/2 is created at the mid-radius of the vacuum flux surfaces. If no error fields are present a vanishingly small n/m  =  5/10 island chain should be present. Modeling indicates that if an n  =  1 perturbing field is applied by the trim coils, a large n/m  =  1/2 island chain will be opened. This island chain is used to create a perturbation large enough to be imaged by the diagnostic. Phase and amplitude scans of the applied field allow the measurement of a small m intrinsic island chain with a phase relative to the first module of the W7-X experiment. These error fields are determined to be small and easily correctable by the trim coil system. [ABSTRACT FROM AUTHOR]