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In this work we introduce eLaBo—an electronic laboratory book system. ELaBo is a tool that enables collaboration of distributed teams by using standard internet browsers. It provides several functions: Users can create books for specific purposes, e.g. an experimental session or for recording on diagnostics. A book contains pages and resources (e.g. binary files), which are created and manipulated by users of the book. A simple wiki syntax is used to edit the contents of pages including formatted text, images, and LaTeX for expressing mathematical equations. ELaBo provides for different types of links, a full-text search for the wiki pages and a version history. Access control is implemented using a key methaphor. Recently (since the last login) modified or created pages or books can be displayed on demand.

Both the plasma poloidal curvature and the curvature of the probing wave-front play an important role for the spectral resolution of microwave reflectometry. The propagation of electromagnetic waves in a cylindrical plasma with a refractive index monotonically decreasing towards its center leads to elongation of the wave-front (i.e. an increase of the radius of curvature near the axis of radiation). Such a phase-front alteration can result in a major modification of the reflectometry response regarding on high k θ fluctuations. At the same time, the curvature of the cutoff surface in cylindrical plasma is always less than the curvature of the cutoff density for an O-mode wave. For specific geometry of the TEXTOR tokamak we perform numerical two-dimensional full-wave reflectometry synthesizing. The response from poloidaly rotating coherent density perturbation was analyzed on the variety of the plasma cutoff curvature and density scale length, which affects the incident wave-front curvature. The simulations are shown that the increase of the incident wave front curvature extends the spectral resolution of conventional reflectometer with gain antennas. On the other hand, the effect from the cutoff curvature is found to be much weaker as compare to the wave-front effect.

Over the last years several components of the TEXTOR diagnostic data management chain were re-engineered to form one integrated data handling system. All re-engineered components are now in use for the daily operation of the TEXTOR experiment; several key parts have been so for several years. Over this time new opportunities became apparent and new features were required; leading to active maintenance and further development. The intention of this paper is to give a short overview of this data management chain and its recent developments.

The old TEXTOR control systems have successfully been updated. The machine control has replaced bytextorCC, a solution based on the software package WinCC produced by Siemens. WinCC, and thereforetextorCC, can be easily integrated with the already available Siemens S5/S7 hardware components. This new system has the advantage that it is based on industrial soft- and hardware components.Therefore, the lifetime of the control system is extended and the maintenance effort is reduced. The installation and commissioning of the new control system was done in parallel to TEXTOR operation. During this time each function was tested and compared with the actual TEXTOR data. All functionality of the former control system was step-by-step replaced. Special attention was given to the visualization, data and error logging. The machine control timing system has been replaced by an in house development in partnership with Siemens. It consists of transmitters and receivers based on PROFIBUS modules and is fully compatible with the pre-existing timing infrastructure. The old programmable function generator (PFG) has been replaced by compact RIO modules, controlled and programmed by Labview. This new PFG system allows to program up to 84 different time dependent signals. In this paper we intent to present a more detailed overview of our, on WinCC-based work, and a first status report on this new control system for TEXTOR.

At TEXTOR extensive collaborations with foreign institutes have been established. For a successful collaboration, the participating scientists must be able to plan the experiment in advance. Therefore they need tools to submit and track their experiment proposals and pulse plans. During and after the experiment access to raw and evaluated data of a TEXTOR discharge is needed to analyze TEXTOR data remotely from the home labs. A goal-oriented data analysis needs in addition a various items of data not recorded with conventional data logging. This discharge specific comments and settings are stored in a logbook. At TEXTOR a logbook with different views is implemented for the scientific experiment and the machine operation, respectively. In a further development towards a TEXTOR experiment management system the information of auxiliary heating devices is stored. The electronic logbook is realized by a client/server approach which makes the access independent from the hard- and software on the client side and allows to access the data and data supplements (metadata) by any common web browsers. All information from TEXTOR is accessible for everybody via a uniform resource locator (URL). The concept of the electronic logbook, the first experience and its possibilities for data analysis will be discussed in this paper.

During the 2002–2003 shutdown of TEXTOR, many components of the TEXTOR diagnostic data management system were upgraded. This paper intents to give an overview of these upgraded components and how they co-operate to form one integrated Data Management System. The components in question are: (1) JDAQ: The Java (or Juelich) Data Acquisition System, a newly created data acquisition system, completely written in the JAVA object oriented programming language. (2) The TEC Common Storage Facility and the Textor Physics Database. (3) The TEC Web-Umbrella: A unified data access scheme based on the widely used HTTP protocol. (4) Chainl: A framework for automatically run chains of analysis software.

The TEC community operates the textor device and in doing so collects and stores data from a number of different front-end acquisition systems, processing codes and analysis systems. Due to the evolution of these systems in the past, different, distributed data storage technologies were used to record this data. In an attempt to reduce the number of interfaces client codes have to use when accessing data from these data stores, an “umbrella” concept was developed: a software-layer that covers (as an “umbrella”) as many as possible of these stores and provides a unified access mechanism to them. We explored the possibility of using the widely supported HTTP protocol for this purpose; this is the core protocol of the World-Wide-Web and it is capable of transporting almost any type of data. The concepts behind using this protocol were based on earlier work at JET. Access via this umbrella has been provided to the most important data stores around textor and access to others is being added regularly. Clients codes, libraries and programs have been developed for several user environments. The HTTP based concepts and the data-access via this system have been found to be highly portable. This paper gives an overview of the TEC Web-Umbrella system, it describes the basic concepts of this system and it presents some of the client-side codes and programs. The paper also reports on some first (tentative) user experiences with it.

A programmable digital signal processing system designed for online measurement and control of fusion devices has been built and operated on TEXTOR–94 tokamak. It meets the following requirements: to give a wide variety of choice in the kind of functions to be performed on the measured signals, stability for a time duration of up to 1 h, at the same time measurement of MHD fluctuations with frequencies in the range of several kHz and isolate the data acquisition from high voltage spikes.The system is being used on TEXTOR e.g. to measure currents and fluxes and to retrieve control parameters from them, to calculate correlations between different signals, or to detect special events like sawtooth crashes.

After the installation of a 110 GHz gyrotron at TEXTOR-94 the development of 110 GHz notch-filter was necessary for protecting the sensitive Electron Cyclotron Emission (ECE)-diagnostic, covering the frequency range 104≤ f ≤148 GHz. The design and construction of a narrow (Δ f ≤1000 MHz) and deep ( A max ≥50 dB) notch filter is explained. Furthermore the behaviour at different modes is studied. Also the influence of the aperture on the width of the notch as well as the influence of the number of used cavities on the depth of the notch and the losses in the pass band is studied and presented in the paper.

This paper presents the extension of the data acquisition and control system JDAQ, used at TEXTOR, to allow different data acquisition hardware. The extension was developed for the INCAA-TR10 and INCAA-TR32 recorders. These modules are built in the “CompactPCI” hardware format. It has been demonstrated that measuring with PCI modules under JDAQ is possible. However, the handling of the modules is not as systematic as measuring with CAMAC modules. General problems with implementation of the PCI modules will be discussed in this paper.

Remote Participation is a widely used term with different meanings. In the fusion community it has gained an increasing interest with the shut down of small experiments and participation of associations in larger experiments. Also at TEXTOR Remote Participation becomes more and more important with an increasing number of collaborations. At TEXTOR we differentiate between active and passive remote experiment participation. In addition potential users of TEXTOR like to be involved in the experiment preparation phase where the experiment schedule and the availability of diagnostic systems is discussed as well. After an experiment joint groups of users like to share the results and communicate with each other. The final step in publishing the results is also made more transparent for the users in a twofold process. Using a web based pinboard to spread the publication within the user community allows an extensive and early discussion of the results.

Wendelstein 7-X being the most advanced stellarator is currently prepared for commissioning at Greifswald. Forschungszentrum Julich is preparing a research programme in the field of plasma wall interactions (PWI) by developing a dedicated set of diagnostic systems. The specific interest at Wendelstein 7-X is to understand PWI processes in presence of a 3D plasma boundary of an island divertor. Furthermore, for the first time steady state plasma at high density and low temperature in the divertor region will be available. Since PWI only could be understood in conjunction with the edge plasma properties the aim of the setup is to observe both the edge plasma as well as surface processes. For optimum combination of different diagnostic methods the edge diagnostic systems are aligned toroidally along one out of five magnetic islands. Main systems are a multipurpose fast probe manipulator, two gas boxes in opposite divertor modules together with two endoscopes each observing the divertor regions, a poloidal correlation reflectometer, a dispersion interferometer in the divertor, and VUV and X-ray spectroscopy in the plasma core. The concept of the diagnostic setup is presented in this paper.

The Multi-Purpose-Manipulator (MPM) has been operated, as a versatile carrier system for probes, since the first campaign OP. 1.1 in 2015 at Wendelstein 7X. The MPM is mounted at the outboard midplane and is able to perform fast plunges through the entire scrape off layer up to the last closed flux surface. In addition, a system for gas injection was commissioned that allowed the use of a dedicated probe head and a port on the existing probes for fueling and impurity seeding experiments. A combined probe, a combination of Langmuir, Mach and magnetic probes, was used. For the second campaign OP. 1.2a in 2017, with an island divertor, an upgraded combined probe, a fluctuation probe, a retarding field analyzer, a Mach probe array, a laser blow off target and a material probe holder were added to the range of plasma edge diagnostics. The new diagnostic probe heads were designed to address specific tasks, such as measuring the edge fluctuations, the ion temperature and the radial Mach number profiles. However, all fast plunging probes were designed such that they provide the most important quantities for SOL characterization (electron temperature, density, radial electric field).