Huston Fernandes

Battelle Memorial Institute · Brookhaven National Laboratory

COMPASS addressed several physical processes that may explain the behaviour of important phenomena. This paper presents results related to the main fields of COMPASS research obtained in the recent two years, including studies of turbulence, L-H transition, plasma material interaction, runaway electron, and disruption physics: Tomographic reconstru...

O-mode frequency-modulated continuous wave (FMCW) reflectometry provides an alternative to magnetic measurements in the determination of the plasma separatrix position for plasma position control. This type of measurement proves to be particularly attractive for the control of future fusion reactors where the harsh radiation environment may damage...

A future thermonuclear fusion reactor relies on the real-time control of, among others, instabilities and plasma position. At the ISTTOK tokamak, a novel approach of a realtime diagnostic system to control the vertical plasma position (in a 100 s closed-loop) was implemented by: (i) developing the Heavy Ion Beam Diagnostic (HIBD) to perform the pos...

National Synchrotron Light Source-II (NSLS-II) is the latest storage ring of 3 GeV energy with the horizontal emittance of the electron beam being 0.9 nm.rad. Nine In-Vacuum Undulators (IVUs) are utilized at the NSLS-II as of February 2016. All IVUs have a unique side window derived from the experience from the CHESS facility in Cornell University....

National Synchrotron Light Source-II (NSLS-II) is the latest storage ring of 3 GeV energy at the Brookhaven National Laboratory (BNL). The horizontal emittance of the electron beam with the currently installed six damping wigglers is 0.9 nm.rad, which could be further reduced to 0.5 nm.rad with more insertion devices (IDs). With only one RF cavity...

Attempts to build MOOLs over major remote laboratories lead to disappointing results in terms of scalability to large student target audience. Nevertheless e-lab framework developed at IST was designed from scratch to serve many simultaneous users attached at the same time to the same remote experiment. Whereas as an alternative many MOOLs infrastr...

e-lab is a remote laboratory which provides the control of real physics experiments over the internet. The robustness of the laboratory framework has allowed the implementation of new experiments outside the main physical laboratory, for instance in high schools and science centres. To reduce costs and the number of maintenance interventions, a new...

The NSLS-II storage ring completed commissioning in 2014 and all project-beamline IDs have also been commissioned. As of February 2015, six beamlines are about to finish commissioning. By the end of 2015, the ring is expected to store 300 mA with top-up injection capability and 500 mA with a second superconducting RF cavity installed in the followi...

The remote laboratories at IST (Instituto Superior Tecnico), e-lab, serve as a valuable tool for education and training based on remote control technologies. Due to the high number and increase of remotely operated experiments a generic protocol was developed to perform the communication between the software driver and the respective experimental s...

Neste trabalho implementa-se um método de medição, em tempo real, da posição de uma esfera metálica suspensa com dois graus de liberdade no interior de uma caixa de paredes condutoras. A geometria da montagem proporciona acoplamentos capacitivos variáveis, que dependem da distância da esfera a cada um dos planos. Com o circuito dimensionado para me...

Measurements of the ion temperature fluctuations by retarding field energy analyzed (RFA) based on two point measurements on the exponentially decaying region of the I-V characteristic with two differently DC biased RFA electrodes have been tested and proved in the experiments on the tokamak ISTTOK. In this paper, a DC operation of an RFA has been...

The first derivative probe technique was applied to study the ISTTOK tokamak plasma. This technique employs the electron part of the Langmuir probe current-voltage (IV) characteristic and yields information on the plasma potential and the electron energy distribution function (EEDF). The IV characteristic was measured with new electrical probes mou...

The paper presents the results of the recent fast electron measurements performed by means of a new measuring head, which was equipped with two Cherenkov-type detectors made of diamonds coated with appropriate absorption filters. The high light efficiency of those detectors enabled a high temporal resolution and a good signal-to-noise ratio to be a...

The ISTTOK tokamak has a long tradition on alternate plasma current (AC) discharges, but the old control system was limiting and lacked full system integration. In order to improve the AC discharges performance the ISTTOK fast control system was updated. This control system developed on site based on the Advanced Telecommunications Computing Archit...

The ISTTOK tokamak was upgraded with a plasma control system based on the Advanced Telecommunications Computing Architecture (ATCA) standard. This control system was designed to improve the discharge stability and to extend the operational space to the alternate plasma current (AC) discharges as part of the ISTTOK scientific program. In order to ac...

This paper presents an overview of the Control, Data Acquisition, and Communication system (CODAC) at the COMPASS tokamak: the hardware set-up, software implementation, and communication tools are described. The diagnostics and the data acquisition are tailored for high spatial and temporal resolution required by the COMPASS physics programme, whic...

The National Synchrotron Light Source-II (NSLS-II) project is now in the final stage of construction. The Linac, the Booster synchrotron, and the Storage Ring magnets girder assemblies have been installed. The first damping wiggler has been delivered and its field characteristics are carefully measured. A Three Pole Wiggler (3PW) and Apple-II type...

A remotely controlled automated apparatus is used to accurately test linear momentum conservation at low friction conditions. Electronic control of the magnetic actuators and photoelectric acquisition system is performed by a dsPIC30 microcontroller, connected to the e-lab platform. Placed at a high school, this experiment aims to encourage electro...

The next step in the Wendelstein stellarator line is the large superconducting device Wendelstein 7-X, currently under construction in Greifswald, Germany. Steady-state operation is an intrinsic feature of stellarators, and one key element of the Wendelstein 7-X mission is to demonstrate steady-state operation under plasma conditions relevant for a...

The paper reports on experimental studies of electron beams in the ISTTOK tokamak, those were performed by means of an improved four-channel detector. The Cherenkov-type detector measuring head was equipped with four radiators made of two types of alumina-nitrate (AlN) poly-crystals: machinable and translucent ones, both of 10 mm in diameter and 2....

The ISTTOK tokamak (Ip=4 kA, BT=0.5 T, R=0.46 m, a = 0.085 m) is one of the few tokamaks with regular alternate plasma current (AC) discharges scientific programme. In order to improve the discharge stability and to increase the number of AC discharge cycles a novel control system was developed. The controller acquires data from 50 analog-to-digita...

In this paper a new plasma experiment, the Paschen Curve, is added to e-lab a remote laboratory. In this experiment the conditions at which the transition from gas to plasma happens are explored by studying breakdown voltage of said gas, that is the voltage at which the plasma is formed, between parallel electrodes as function of pressure and the d...

As the length of insertion devices (ID's) increase for synchrotron light sources, so does the need to have larger ultra high vacuum (UHV) sealed chambers, which in turn necessitates the use of creative ways of sealing these large chambers in the UHV range (10-11 torrs).The method specified below was used to seal a 4-meter test vacuum chamber succes...

e-lab is a remote laboratory infrastructure, powered by a software framework designed for distributed data collection, that allows to perform experiments and retrieve data from a remote apparatus. In this demonstration we will present the e-lab interface properties and its modus operandi, giving as well some topics of complimentary software use for...

The Heavy Ion Beam Diagnostic (HIBD) on the tokamak ISTTOK (a = 8.5 cm, R = 46 cm and BT = 0.5 T) has been used to measure profiles of plasma electron density and temperature and plasma potential. Recently, HIBD has been upgraded for the measurements of local fluctuations of the neσ eff product across the plasma cross-section. The HIBD upgrade has...

Embryonic chimerism - mixing of cells originated from at least two different fertilizations - has been used as a tool for stem cell pluripotency diagnosis, transgenic rodent production, and organogenesis studies. Additionally, parthenotes are used for studies related to gene imprinting and the ability of their cells to compose the placenta and/or a...

The tokamak ISTTOK havy ion beam diagnostic (HIBD) operates with a multiple cell array detector (MCAD) that allows for the plasma density and the plasma density fluctuations measurements simultaneously at different sampling volumes across the plasma. To improve the capability of the plasma density fluctuations investigations, a new detection system...

The Vertical Stabilization system of the JET tokamak has been recently upgraded. This new system enables a more sensitive control of the plasma geometry and can withstand larger perturbations, enabling scientists to push the plasma performance to its limits without risking a severe control loss, which might endanger the machine integrity. The proje...

A diagnostic technique based on the Cherenkov effect is proposed for detection and characterization of fast (super-thermal and runaway) electrons in fusion devices. The detectors of Cherenkov radiation have been specially designed for measurements in the ISTTOK tokamak. Properties of several materials have been studied to determine the most appropr...

E-lab is a remote laboratory infrastructure, powered by a specific software framework, that allows to perform experiments and retrieve data from a remote apparatus. The deployment of new experiments on this platform is a complex and demanding process and an integrated overview for it is missing. An overview of e-lab's specifications is presented ta...

e-lab is a remote laboratory infrastructure, powered by a specific software framework, that allows to perform experiments and retrieve data from a remote apparatus. The deployment of new experiments on this platform is a complex and demanding process and an integrated overview for it is missing. An overview of e-lab's specifications is presented ta...

In a tokamak, the accurate estimation of the plasma boundary is essential to maximise the fusion performance and is also the first line of defence for the physical integrity of the device. In particular, the first wall components might get severely damaged if over-exposed to a high plasma thermal load. The most common approach to calculate the plas...

A pinhole probe (PHP) for the simultaneous measurement of the parallel, T(parallel), and perpendicular, T(perpendicular), ion temperature has been designed and tested in the scrape-off-layer (SOL) plasma of the tokamak ISTTOK. The PHP consists of a tunnel immersed into the plasma parallel to magnetic field and an ion collector. One end of the tunne...

The production of embryonic chimeras has been studied as a tool for in vivo pluripotency validation in embryonic stem cells (ESC) as well as to produce transgenic mice. Among the techniques to produce chimeras, one of the most used is microinjection (MI) of ESC into blastocysts or in the perivitelline space (PVS) of the embryos with 4 to 8 cells. A...

The Vertical Stabilization system of the JET tokamak has been recently upgraded. This new system enables a more sensitive control of the plasma geometry and can withstand larger perturbations, enabling scientists to push the plasma performance to its limits without risking a severe control loss, which might endanger the machine integrity. The proje...

This paper is a reflection on the potential of learning communities in the Web 2.0 in terms of learning (formal and informal) for young people. Specifically, it focuses on the integration of real remote laboratories like " e-lab.ist.eu " in the community of students and teachers of secondary education-"FQ em rede" and how it can expand and flatten...

High temperature superconductors (HTS) are very attractive to be used in fusion devices mainly due to lower operations costs. The HTS technology has reached a point where the construction of toroidal field coils for a tokamak is possible. The feasibility of a tokamak operating with HTS is extremely relevant and ISTTOK is the ideal candidate for a m...

Remote participation is a key success factor for worldwide organizations and video-conference is an important aspect when laboratory collaborators are geographically dispersed.Several tools for video-conference are available worldwide. However, there is a need for a default integrated set of tools which provide all the needed features for remote pa...

The use of liquid metals such as lithium and gallium have been pointed out as a suitable solution to solve problems related to the use of solid walls submitted to high power loads. A proper use of liquid materials in fusion reactors depends, among others, on their affinity to retain hydrogenic isotopes. While retention in lithium has been studied i...

The Multithreaded Application Real-Time executor (MARTe) software provides an environment for the hard real-time execution of codes while leveraging a standardized algorithm development process. The Experimental Physics and Industrial Control System (EPICS) software allows the deployment and remote monitoring of networked control systems. Channel A...

A real-time plasma position control system is mandatory to achieve long duration (up to 250 ms), Alternating Current (AC) discharges on the ISTTOK tokamak. Such a system has been used for some time supported only on magnetic field diagnostic data. However, this system is clearly challenged when the plasma current is low, rendering it inoperative du...

The main concern in using free flowing liquid metals in fusion devices is related to their interaction with magnetic fields. On ISTTOK tokamak, liquid gallium jets are injected deep into the plasma along a vertical direction. The influence of the plasma interaction on the jet has been investigated monitoring the liquid metal behavior using a fast f...

The retarding field analyzer (RFA) is a widely used diagnostic tool for the ion temperature measurement in the scrape-off-layer (SOL) of the thermonuclear plasma devices. However, the temporal resolution in the standard RFA application is restricted to the ms timescale. In this paper, a dc operation of the RFA is considered, which allows for the me...

A visible synchrotron light monitor (SLM) beam line has been designed at the NSLS2 storage ring, using the bending magnet radiation. A retractable thin absorber will be placed in front of the first mirror to block the central x-rays. The first mirror will reflect the visible light through a vacuum window. The light is guided by three 6-inch diamete...

Measurements of fast electrons, as performed during recent few years in small tokamaks, demonstrated that detectors based on the Cherenkov effect are very useful tools for such studies. The modernized measuring heads, which were equipped with miniature aluminum-nitride (AlN) radiators, enabled to determine locations and instants of the fast electro...

The paper describes measurements of fast run-away electron beams emitted from a plasma torus in the ISTTOK tokamak, which were performed by means of a new Cherenkov-type detector equipped with four radiators made of aluminium-nitrate (AlN) crystals of 10 mm in diameter and 2.5 mm in thickness each. The measuring head was fixed to a movable support,...

Embryonic stem cells (ESC) have been used in attempts to obtain specific tissues or even individuals. Embryonic stem cells are pluripotent, allowing the differentiation of cell types from 3 germ layers. The establishment of a stable lineage of ESC is a valuable tool; however, some strains of mice are less permissive to ESC derivation or generation...

The paper describes experimental studies of electron beams emitted from a plasma torus within the ISTTOK tokamak, which were performed by means of a new four-channel detector of the Cherenkov type. A range of electron energy was estimated. There were also measured hard X-rays, and their correlation with the fast run-away electron beams was investig...

The paper concerns detectors of the Cherenkov radiation which can be used to measure high-energy electrons escaping from short-living plasma. Such detectors have high temporal (about 1 ns) and spatial (about 1 mm) resolution. The paper describes a Cherenkov-type detector which was designed, manufactured and installed in the ISTTOK tokamak in order...

A diagnostics capable of characterizing the runaway and superthermal electrons has been developing on the ISTTOK tokamak. In previous paper, a use of single-channel Cherenkov-type detector with titanium filter for runaway electron studies in ISTTOK was reported. To measure fast electron populations with different energies, a prototype of a four-cha...

The next generation of large-scale physics experiments will be highly complex, raise new challenges in the field of control and automation systems and demand well integrated, interoperable set of tools with a high degree of automation. Fusion experiments will face similar needs and challenges. In nuclear fusion activities, e.g., JET and other devic...

The principle of the mass-sensitive ion probe (MSIP) operation consists in a time-of-flight (TOF) analysis of the ions in the burst excited by a short (µ s-range) voltage pulse applied to a small grid immersed into the plasma. The ions in the burst propagate along the magnetic field lines of the tokamak with velocities determined by the value of th...

A superestimulação visando a produção embrionária, em camundongos, é um procedimento multifatorial. Para minimizar o número de animais sacrificados e maximizar o resultado do tratamento superestimulatório, é necessário que haja uma predição do risco de não obter embriões de determinado animal. Este trabalho objetivou avaliar se as variáveis - conce...

The IST/EURATOM Association is developing a new generation of control and data acquisition hardware for fusion experiments based on the ATCA architecture. This emerging open standard offers a significantly higher data throughput over a reliable High Availability (HA) mechanical and electrical platform. One of this ATCA boards has 32 galvanically is...

The COMPASS tokamak has started its operation recently in Prague and to meet the necessary operation parameters its real-time system, for data processing and control, must be designed for both flexibility and performance, allowing the easy integration of code from several developers and to guarantee the desired time cycle. For this purpose an Advan...

Modern fusion experiments require the presence of several subsystems, responsible for the different parameters involved in the operation of the machine. With the migration from the pre-programmed to the real-time control paradigm, their integration in Control, Data Acquisition, and Communication (CODAC) systems became an important issue, as this im...

Instruments for Control and Data Acquisition (CDAQ) require a pervasive embedded network able to provide accurate timing and synchronization signals to all digitalization/reconstruction devices and control processes of a CDAQ system. Typically, the industry trend is to adopt a well established computer instrumentation standard and complement it wit...

A real-time plasma position control system is mandatory to achieve long duration (up to 250ms), Alternating Current (AC) discharges on the ISTTOK tokamak. Such a system has been used for some time supported only on magnetic field diagnostic data. However, this system is clearly challenged when the plasma current is low, rendering it inoperative dur...

The Multithreaded Application Real-Time executor (MARTe) is a data driven framework environment for the development and deployment of real-time control algorithms. The main ideas which led to the present version of the framework were to standardise the development of real-time control systems, while providing a set of strictly bounded standard inte...

The COMPASS tokamak has started operation at the IPP Prague in December 2008. A new control system has been built using an ATCA-based real-time system developed at IST Lisbon. The control software is implemented on top of the MARTe real-time framework attaining control cycles as short as 50 μs, with a peak jitter of less than 9 μs. The controlled p...

Development of real-time applications is usually associated with nonportable code targeted at specific real-time operating systems. The boundary between hardware drivers, system services, and user code is commonly not well defined, making the development in the target host significantly difficult. The Multithreaded Application Real-Time executor (M...

This paper presents a slow control system based on Experimental Physics and Industrial Control System (EPICS) and FireSignal technology for fusion devices, that is being developed for ISTTOK and COMPASS tokamaks. In this approach, the machine sub-systems control is based in micro-controllers. These sub-systems can handle automatically the necessary...

The presently available processing power in generic processing units (GPU) combined with state-of-the-art programmable logic devices enables the implementation of complex algorithms for plasma diagnostics in a real-time scenario.A tomography diagnostic based on three linear pin-hole cameras each with eight lines of sight has been developed for the...

This study deals with SiO2–P2O5 powders obtained by sol–gel process, starting from tetraethoxysilane (TEOS) as precursor for SiO2 and either triethylphosphate (TEP) or phosphoric acid (H3PO4) as precursors for P2O5. In the case of samples prepared with H3PO4, TG–DTA data showed an accentuated weight loss associated to an endothermic effect up to ab...

The 3rd International Joint Experiment has been carried out on ISTTOK following the last RUSFD (technical meeting on Research Using Small Fusion Devices) conference, held at Lisbon, in the scope of the IAEA Coordinated Research Project. This program has allowed a great knowledge interchange among the “small” fusion devices community and, in particu...

It is recognized that the broad-band fluctuations observed in plasmas of thermonuclear devices are the cause of anomalously large energy and particle transport. Strong progress has been achieved on different plasma devices using a heavy ion beam probe (HIBP) diagnostic measuring the plasma potential and density fluctuations. Better understanding of...

This paper presents an overview of the results obtained during the Joint Experiments organized in the framework of the IAEA Coordinated Research Project on 'Joint Research Using Small Tokamaks' that have been carried out on the tokamaks CASTOR at IPP Prague, Czech Republic (2005), T-10 at RRC 'Kurchatov Institute', Moscow, Russia (2006), and the mo...

This research effort focused on the development of an automatic road incident detection and characterization system which will lead to the reduction of non-recurrent traffic congestion on freeways. An algorithmic methodology was developed for incorporation and enhancement of the existing South Carolina Department of Transportation (SCDOT) evacuatio...

The Compass tokamak is currently being installed in Prague, Czech Republic. Its control and data acquisition system is being redesigned and built from scratch and it will be based on novel digital technologies. The proposed hardware for the controller is based on the PICMG 3.0 Advanced Telecommunications Computing Architecture ™ (ATCA) standard. Th...

The amount of data generated by the infra-red and visible cameras at ITER is expected to be considerably larger than most diagnostics. ITER will have 12 infra-red cameras plus 12 visible cameras in four different equatorial port plugs. Each of the ports will have a Plant System Host (PSH) that will provide a standard image of the plant system to th...

A new framework for the development and execution of real-time codes is currently being developed and commissioned at JET. The foundations of the system are Linux, the Real Time Application Interface (RTAI) and a wise exploitation of the new i386 multi-core processors technology.The driving motivation was the need to find a real-time operating syst...

Purpose The fusion energy research in Europe is developed by a set of laboratories of different countries and organisations. EFDA is an organisation whose main objective is to promote and improve the coordination and collaboration among these laboratories. This paper sets out to describe a working federation (EFDA‐Fed) that gathers EFDA (as organis...

Gas, fluid, or solid Cherenkov-type detectors have been widely used in high-energy physics for determination of parameters of charged particles, which are moving with relativistic v