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Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil IPAC 2021, Campinas, Brazil, 24 May 2021 - 28 May 2021; JACoW Publishing, Geneva, Switzerland 3 pp. (2021). doi:10.18429/JACOW-IPAC2021-WEPAB131, A compact THz radiation facility based on the principle of a pre-bunched Free Electron Laser, called Delhi Light Source (DLS) is at the final stage of commissioning at IUAC, New Delhi, India. For generation of THz radiation in DLS, an undulator with period length of 48 mm (U48), built by HZB and refurbished at DESY will be used. The magnetic tuning and the field measurements have been done on the U48 along with the design and installation of correction coils at the entrance/exit of the U48. In addition, horizontal and vertical ambient field correction coils were integrated into the magnet girders. A quadrupole correction coil along the vacuum chamber in order to mitigate the defocusing effect of the U48 on the electron beam has been designed. The current through all coils has been adjusted as a function of the gap by the new control system designed for the U48. In addition, an extruded aluminium vacuum chamber was designed and fabricated and will be aligned with the the undulator soon., Published by JACoW Publishing, Geneva, Switzerland

Mit der Einführung, Veröffentlichung und bundesweiten Verbreitung der Bildungsstandards Geographie durch die Deut sche Gesellschaft für Geographie (DGfG) im Jahre 2006 ging auch die Hoffnung auf eine sukzessive Implementierung einher, welche darin resultieren sollte, dass sich die Bildungsstandards sowohl im non-formalen Unterrichtsalltag als auch im formalisierten Kontext der Lehrpläne bzw. Curricula der einzelnen Länder der BRD wiederfinden. Gleichwohl fehlen hinsichtlich einer solchen paper implementation bislang entsprechende Forschungserkenntnisse, so dass die Frage nach dem tatsächlichen Impact der Standards im Schulwesen noch als unbeantwortet gelten muss. Vorliegender Artikel vergleicht den bayerischen Gymnasiallehrplan Geographie (2004/2009) mit dem neuen, 2017 in-Kraft-tretenden LehrplanPLUS Gymnasium Geographie unter dem Aspekt der Implementierung des Kompetenzmodells der Bildungs standards Geographie. In übergeordneter Sichtweise versteht er sich als Beitrag zur Entwicklung einer geographiedi daktischen Implementierungsforschung. Dabei soll der Frage nachgegangen werden, ob und ggf. in welchem Diffe renzierungsgrad sich das Kompetenzmodell der Bildungsstandards im neuen Lehrplan wiederfindet, dort also formal implementiert ist. Als methodischer Rahmen dient hierbei ein neu entwickeltes Analyseinstrument auf Grundlage der qualitativen Inhaltsanalyse. Wie die Ergebnisse der vorgestellten Studie zeigen, kann in Bayern eine Weiterentwick lung des Geographielehrplans hin zu einer expliziten Kompetenzorientierung konzediert werden, die mit einer deutlich nachweisbaren paper implementation der Bildungsstandards Geographie der DGfG im neuen LehrplanPLUS Geogra phie einhergeht. Bei detaillierterer Betrachtung zeigt sich gleichwohl, dass die inhaltliche Übereinstimmung mit den Bildungsstandards im Bereich der sechs Kompetenzbereiche am höchsten ist, über die Ebene der 24 Kompetenzen bis zu den 77 Einzelstandards jedoch insgesamt sukzessive sinkt und mitunter erheblich variiert, When the Educational Standards in Geography for the Intermediate School Certificate were published for the first time in 2006, a successive implementation process was expected. One result sought was the integration of the Educational Standards in both school lessons as well as in formal contexts such as the curricula. However, as of today, there is a con siderable lack in according research findings of such a paper implementation, and the question of the particular impact of the Educational Standards on the curricula of the different types of schools within Germany remains mostly unanswered. In the article presented here, the Bavarian grammar school (Gymnasium) curriculum Geography of 2004 (slightly alterna ted in 2009) is compared to the new curriculum LehrplanPLUS Geography, which is due to be implemented in 2017, with a particular focus on the formal implementation of the competence model of the Educational Standards. From an overall perspective, the study can be regarded as a contribution to an emerging school of didactic implementation research. A newly developed research tool set to analyze formal paper implementation results based on concepts of a qualitative content analysis. As the results presented reveal, the overall implementation and integration of the competence model of the Educational Standards into the new Bavarian Geography curriculum (Gymnasium) via paper implementation can be confirmed. Yet, a more detailed view shows that the level of re-installment varies, from high (areas of competence) to lower (particular standards), with significant differences concerning the particular single abilities.

Up to the publication of the results of Germany’s first participation in the PISA study in 2001, there hadbeen no national educational standards in Germany’s 16 federal states. In the aftermath of the discussionsabout the disappointing outcomes, Germany’s federal states decided to develop national standards, yetfocusing on “core subjects” and leaving geography disregarded. Consequently, the DGfG, which is thegoverning body of all professional geography associations in Germany, agreed on solving the problem onits own and published its own Educational Standards in Geography in 2006. Even though there have beencountless efforts to foster the implementation of these widely-accepted, yet without legislative validation,standards we do not know exactly to what extent they have been implemented in the particular Germanfederal states. The study presented here addresses this research gap bifid: Firstly, a research tool designedto analyze the paper implementation (i.e. putting into place new policies and procedures with the adoptionof an innovation as the rationale for the policies and procedures, Fixsen et al., 2005, p. 6) of standards incurricula is introduced. Secondly, the results of a thorough examination of all curricula valid for thegrammar schools in Germany are presented and discussed. As it becomes obvious, the EducationalStandards have become increasingly implemented within the past years despite a lack of support by thelegislations of the 16 federal states. However, there are some gaps that remain to be closed in order toensure a complete, entirely successful paper implementation, ranging from particular areas of competencewithin the curricula in some states that have not adopted standards based geography instruction.&nbsp

This paper reports about aspects of design, manufacturing, and commissioning of the 12 FLASH2 variable gap undulator segments. The accuracy of gap drive and encoder systems was tested by magnetic measurements; changes in the phase error proved to be a highly sensitive probe to verify a reproducibility of 1 μm. After magnetic tuning of the IDs, the remaining gap dependence in the field integrals could be successfully compensated by corrector coils. Inconsiderate handling of components during assembling necessitated an elaborate demagnetisation process before the tuning could start., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

In the new octant of PETRA~III, there are 14 undulator beamlines covering photon energy range from 0.3keV to 150keV. There are also 80m of damping wigglers in order to achieve a low emittance of 1nmrad. Some of these devices, operating at PETRAIII since 2008, accumulated total radiation doses of about 100kGy. Visible corrosion at the magnet structures of some permanent magnet undulators setting in after a few years and a high dose rate measured regularly by thermoluminescent dosimeters (TLDs) gave reason to inspect the magnetic field of all insertion devices in the PETRA tunnel. This paper presents details of the magnetic field degradation caused by radiation damage to the undulator magnets. For some undulators changes in the spectral properties of the generated light were observed. It was measured with different taper settings in order to partly compensate the nonuniform demagnetization along the structure. The results are compared with the data from the sFLASH undulators and measurements of special 3 pole "sacrificial" undulator, installed in FLASH. Its magnetic field is periodically remeasured and shows field amplitude decrease of 1% per 16kGy accumulated dose., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany International Particle Accelerator Conference IPAC, IPAC 2014, Dresden, Germany, 15 Jun 2014 - 20 Jun 2014; Geneva : JACoW, Geneva, Switzerland 1235-1237 (2014). doi:10.18429/JACoW-IPAC2014-TUPRO084, The present fixed-gap undulator system for FLASH1 and the new FLASH2 undulators will share the same electron beam accelerator, thus 12 variable gap undulators are needed in order to provide radiation of different wavelengths to both experimental halls independently. Each of the 12 devices has a length of 2.5m. The magnet structure with a period length of 31.4mm provides a maximum field of 0.96T with an effective K-parameter of 2.81 at minimum gap. Phase, vertical and horizontal trajectories have been tuned based on Hall probe and stretched wire measurements. Remaining multipoles were optimized with moderate gap dependence by using magic fingers. At some magnet structures, shims were placed to correct gap dependent field integrals. All undulators have an rms vertical and horizontal trajectory flatness, Published by JACoW, Geneva, Switzerland, Geneva

A seeded free-electron laser (FEL) experiment at VUV wavelengths, called sFLASH, is being prepared at the existing SASE FEL user facility FLASH. Seed pulses at wavelengths around 35 nm from high harmonic generation (HHG) will interact with the electron beam in sFLASH undulators upstream of the existing SASE undulator section. In this paper the tuning results and performance of the sFLASH undulators are presented., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Zum theoretischen Verständnis moderner Hochleistungslegierungen und deren zielgerichtete Weiterentwicklung ist die Kenntnisse der effektiven Paar-Wechselwirkungspotentiale von entscheidender Bedeutung. Mit der diffusen Nahordnungsstreuung ist ein experimenteller Zugang zu diesen Potentialen in binären Legierungskristallen möglich. In dieser Arbeit wird eine neue Technik zur Messung diffuser Streusignale von vorgestellt, welche auf der Verwendung von hochenergetischen Röntgenstrahlen und Flächendetektoren basiert. Im Vergleich zu herkömmlichen Methoden mit Punktzählern wird damit eine höhere Datenqualität bei gleichzeitiger Verringerung der Meßzeit um mehrere Größenordnungen erreicht. Zu diesem Zweck wurde auch eine spezielle HV-Probenumgebung konstruiert. Erste Experimente wurden an Kristallen der als wohlverstanden geltenden Modellsysteme für Ordnungsphänomene Cu3Pd- und Cu3Au durchgeführt. Dabei war es erstmals möglich, mit Hilfe von Röntgenbeugung ein Abbild der durch die Fermi-Oberflächen induzierten Abschirmeffekte in der Nahordnung dieser beiden binären Legierungen zu erhalten. Bei Experimenten am System Cu-Mn wurden deutliche Anzeichen für ein nichtanalytisches Verhalten der effektiven Wechselwirkungspotentiale und damit auch der diffusen Nahordnungsstreuung in der Umgebung des Gamma-Punktes beobachtet. Dies bestätigt Vorhersagen neuer effizienter Methoden zur theoretischen Beschreibung der Energetik und des Nahordnungsverhaltens binärer Systeme. Im System Au-Ni konnten durch die parallele Datenerfassung in ganzen Ebenen des reziproken Raums konkurrierende Nahordnungstendenzen beobachtet werden. Weiterhin erlaubte die Zeitauflösung der Meßmethode, die Nukleationsprozesse bei der Entmischung des Systems in-situ zu beobachten. Dabei zeigten sich zwei unterschiedliche Nukleationskanäle, die auf einen sehr komplexen Einfluß des Wechselwirkungspotentials auf den Phasenseparationsprozeß in diesem System hindeuten., Information about the effective pair interaction potentials is essential for the theoretical understandig of todays high-performance multicomponent alloys. Without this data a purposive design of new alloys is not feasible. An experimental tool which gives access to these potentials in crystalline materials is diffuse scattering. In this thesis a new experimental technique for recording the diffuse scattering from crystals is presentend. It is based on the application of high energy X-rays and area detectors. In comparison to conventional techniques using point detectors the data aquisition time can be decreased by several orders of magnitude while the quality of the datasets is incrased. For this purpose a special sample environment was designed. First experiments were carried out on Cu3Au- and Cu3Pd-crystals, which are known as model systems for ordering phenomena in binary alloys. Subtle effects on the short range order which are induced by screening effects related to the Fermi surface in these alloys were clearly visible in the recorded images. It was the first time these effects could be resolved quantitavely using X-ray diffraction. Experiments on the Cu-Mn system revealed clear indications for a nonalytic behaviour of the effective pair interaction potentials at the Gamma-point. This phenomenon was predicted by new and effcient theoretical concepts for the description of the energetics and ordering phenomena in binary alloys. In the experiments on the phase separating Au-Ni system different competing short range ordering tendencies could be observed. This was possible due to the capability of parallel recording of the intensity in entire planes of reciprocal space. The time resolution of the experimental technique made it feasible to observe in-situ two different nucleation channels during phase separation. This points towards complex effects of the effective pair interaction potential on kinetic phenomena in Au-Ni.