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341 results on '"Skiba, Mateusz"'

301. The merits of ion cyclotron resonance heating schemes for sawtooth control in tokamak plasmas

Author: Chapman, I. T., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Chapman, I. T., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: JET experiments have compared the efficacy of low-and high field side ion cyclotron resonance heating (ICRH) as an actuator to deliberately minimise the sawtooth period. It is found that low-field side ICRH with low minority concentration is optimal for saw tooth control for two main reasons. Firstly, low-field side heating means that any toroidal phasing of the ICRH (-90 degrees, +90 degrees or dipole) has a destabilising effect on the sawteeth, meaning that dipole phasing can be employed, since tins is preferable due to less plasma wall interaction from Resonant Frequency (RI) sheaths. Secondly, the resonance position of the low field side ICRH does not have to be very accurately placed to achieve saw tooth control, relaxing the requirement for real-time control of the RF frequency. These empirical observations have been confirmed by hybrid kinetic-magnetohydrodynamic modelling, and suggest that the ICRH antenna design for ITER is well positioned to provide a control actuator capable of having a significant effect on the sawtooth behaviour., For complete list of authors see http://dx.doi.org/10.1017/S0022377815000987
Published: 2015
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302. Pedestal confinement and stability in JET-ILW ELMy H-modes

Author: Maggi, C. F., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Maggi, C. F., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: New experiments in 2013-2014 have investigated the physics responsible for the decrease in H-mode pedestal confinement observed in the initial phase of JET-ILW operation (2012 Experimental Campaigns). The effects of plasma triangularity, global beta and neutrals on pedestal confinement and stability have been investigated systematically. The stability of JET-ILW pedestals is analysed in the framework of the peeling-ballooning model and the model assumptions of the pedestal predictive code EPED. Low D neutrals content in the plasma, achieved either by low D-2 gas injection rates or by divertor configurations with optimum pumping, and high beta are necessary conditions for good pedestal (and core) performance. In such conditions the pedestal stability is consistent with the peeling-ballooning paradigm. Moderate to high D-2 gas rates, required for W control and stable H-mode operation with the ILW, lead to increased D neutrals content in the plasma and additional physics in the pedestal models may be required to explain the onset of the ELM instability. The changes in H-mode performance associated with the change in JET wall composition from C to Be/W point to D neutrals and low-Z impurities playing a role in pedestal stability, elements which are not currently included in pedestal models. These aspects need to be addressed in order to progress towards full predictive capability of the pedestal height., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/11/113031
Published: 2015
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303. Inferring divertor plasma properties from hydrogen Balmer and Paschen series spectroscopy in JET-ILW

Author: Lomanowski, B. A., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Lomanowski, B. A., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: A parametrised spectral line profile model is formulated to investigate the diagnostic scope for recovering plasma parameters from hydrogenic Balmer and Paschen series spectroscopy in the context of JET-ILW divertor plasmas. The separate treatment of Zeeman and Stark contributions in the line model is tested against the PPP-B code which accounts for their combined influence on the spectral line shape. The proposed simplified model does not fully reproduce the Stark-Zeeman features for the alpha and beta transitions, but good agreement is observed in the line width and wing profiles, especially for n > 5. The line model has been applied to infer radial density profiles in the JET-ILW divertor with generally good agreement between the D 5 -> 2, 5 -> 3, 6 -> 2, 7 -> 2 and 9 -> 2 lines for high recycling and detached conditions. In an L-mode detached plasma pulse the Langmuir probe measurements typically underestimated the density by a factor 2-3 and overestimated the electron temperature by a factor of 5-10 compared to spectroscopically derived values. The line model is further used to generate synthetic high-resolution spectra for low-n transitions to assess the potential for parameter recovery using a multi-parametric fitting technique. In cases with 4 parameter fits with a single Maxwellian neutral temperature component the D 4 -> 3 line yields the best results with parameter estimates within 10% of the input values. For cases with 9 parameter fits inclusive of a multi-component neutral velocity distribution function the quality of the fits is degraded. Simultaneous fitting of the D 3 -> 2 and 4 -> 3 profiles improves the fit quality significantly, highlighting the importance of complementary spectroscopic measurements for divertor plasma emission studies., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/12/123028
Published: 2015
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304. Transport analysis and modelling of the evolution of hollow density profiles plasmas in JET and implication for ITER

Author: Baiocchi, B., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Baiocchi, B., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: The density evolution during the transient phase just after the L-H transition is investigated using theoretical transport models. Cases characterized by core densities which evolve in longer timescales than the edge densities, leading to hollow density profiles (R/L-n = -R del n/n < 0) are modelled. This density evolution is particularly interesting because it has been shown to be beneficial in the view of the access to burning plasma conditions in ITER (Loarte et al 2013 Nucl. Fusion 53 083031). Self-consistent simulations of the JET discharge 79676 of the density-only, and of the density and the temperatures are carried out using a quasilinear gyrokinetic code, QuaLiKiz (Bourdelle et al 2007 Phys. Plasmas 14 112501), coupled with a transport code CRONOS (Artaud et al 2010 Nucl. Fusion 50 043001). The slow evolution of the hollow density, associated with the self-consistently calculated hollow NBI particle deposition, is well reproduced in the plasma core. Indeed, QuaLiKiz is shown to reproduce nonlinear gyrokinetic heat and particle fluxes well for both positive and negative R/L-n. That gives a theoretical and general basis for the persistence of the hollowness, laying the groundwork for the extrapolation to ITER., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/12/123001
Published: 2015
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305. Radiation asymmetries during the thermal quench of massive gas injection disruptions in JET

Author: Lehnen, M., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Lehnen, M., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: Radiation asymmetries during disruption mitigation by massive gas injection (MGI) can result in substantial first wall heat loads in ITER and have, therefore, to be minimised. This paper gives a first analysis of the relation between the magnetohydrodynamic instabilities governing the thermal quench (TQ) and the toroidal distribution of the radiated power during MGI experiments at JET. It is found that the radiation asymmetry is closely linked to the toroidal phase of the n = 1 mode. The mode phase, on the other hand, is influenced by the injection itself, with the O-point of the mode being displaced towards the injection location. The development of a m = 1 component during the TQ has been identified from temperature and soft x-ray measurements. The observations suggest that the TQ mechanism during MGI is the same as for density limit disruptions. High energy plasmas show a much smaller peaking compared to Ohmically heated plasmas. Neon injection has the tendency towards lower radiation peaking compared to argon injection., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/12/123027
Published: 2015
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306. First dust study in JET with the ITER-like wall : sampling, analysis and classification

Author: Baron-Wiechec, A., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Baron-Wiechec, A., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: Results of the first dust survey in JET with the ITER-Like Wall (JET-ILW) are presented. The sampling was performed using adhesive stickers from the divertor tiles where the greatest material deposition was detected after the first JET-ILW campaign in 2011-2012. The emphasis was especially on sampling and analysis of metal particles (Be and W) with the aim to determine the composition, size, surface topography and internal dust structure using a large set of methods: high-resolution scanning and transmission electron microscopy, focused ion beam, electron diffraction and also wavelength and energy dispersive x-ray spectroscopy. The most important was the identification of beryllium dust both in the form of flakes and droplets with dimensions in the micrometer range. Tungsten, molybdenum, inconel constituents were identified along with many impurity species. The particles are categorised and the origin of the various constituents discussed., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/11/113033
Published: 2015
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307. JET and COMPASS asymmetrical disruptions

Author: Gerasimov, S. N., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Gerasimov, S. N., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Nataliia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: Asymmetrical disruptions may occur during ITER operation and they may be accompanied by large sideways forces and rotation of the asymmetry. This is of particular concern because resonance of the rotating asymmetry with the natural frequencies of the vacuum vessel (and other in-vessel components) could lead to large dynamic amplification of the forces. A significant fraction of non-mitigated JET disruptions have toroidally asymmetric currents that flow partially inside the plasma and partially inside the surrounding vacuum vessel ('wall'). The toroidal asymmetries (otherwise known as the appearance of 3D structures) are clearly visible in the plasma current (I-p) and the first plasma current moments. For the first time we present here the asymmetries in toroidal flux measured by the diamagnetic loops and also propose a physical interpretation. The presented data covers the period of JET operation with a C-wall (JET-C from 2005 until late 2009) and with an ITER-like wall (JET-ILW from 2011 until late 2014), during which pick-up coil and saddle loop data at four toroidally orthogonal locations were routinely recorded. The observed rotations of the Ip asymmetries are in the range from -5 turns to +10 turns (a negative value is counted to the negative plasma current). Initial observations on COMPASS of asymmetric disruptions are presented, which are in line with JET data. The whole of the JET-ILW disruption database and the limited number of COMPASS disruptions examined confirm that the development of the toroidal asymmetry precedes the drop to unity of q95. It is shown that massive gas injection (MGI), which is routinely used to mitigate disruptions, significantly reduces the I-p asymmetries in JET. However, MGI produces fast plasma current quench and consequently high vessel eddy currents, which expose the machine to additional stresses. The effect of the large gas quantity used during the injection is of particular concern as well., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/11/113006
Published: 2015
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308. Discriminating the trapped electron modes contribution in density fluctuation spectra

Author: Arnichand, H., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Arnichand, H., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: Quasi-coherent (QC) modes have been reported for more than 10 years in reflectometry fluctuations spectra in the core region of fusion plasmas. They have characteristics in-between coherent and broadband fluctuations as they oscillate at a marked frequency but have a wide spectrum. This work presents further evidences of the link recently established between QC modes and the trapped electron modes (TEM) instabilities (Arnichand et al 2014 Nucl. Fusion 54 123017). In electron cyclotron resonance heated discharges of Tore Supra, an enhancement of QC modes amplitude is observed in a region where TEM cause impurity transport and turbulence. In JET Ohmic plasmas, QC modes disappear during density ramp-up and current ramp-down. This is reminiscent of Tore Supra and TEXTOR observations during transitions from the linear Ohmic confinement (LOC) to the saturated Ohmic confinement (SOC) regimes. Evidencing TEM activity then becomes experimentally possible via analysis of fluctuation spectra., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/9/093021
Published: 2015
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309. Influence of the E X B drift in high recycling divertors on target asymmetries

Author: Chankin, A. V., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Chankin, A. V., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: Detailed analysis of convective fluxes caused by E x B drifts is carried out in a realistic JET configuration, based on a series of EDGE2D-EIRENE runs. The EDGE2D-EIRENE code includes all guiding centre drifts, E x B as well as. B and centrifugal drifts. Particle sources created by divergences of radial and poloidal components of the E x B drift are separately calculated for each flux tube in the divertor. It is demonstrated that in high recycling divertor conditions radial E x B drift creates particle sources in the common flux region (CFR) consistent with experimentally measured divertor and target asymmetries, with the poloidal E x B drift creating sources of an opposite sign but smaller in absolute value. That is, the experimentally observed asymmetries in the CFR are the opposite to what poloidal E x B drift by itself would cause. In the private flux region (PFR), the situation is reversed, with poloidal E x B drift being dominant. In this region poloidal E x B drift by itself contributes to experimentally observed asymmetries. Thus, in each region, the dominant component of the E x B drift acts so as to create the density (and hence, also temperature) asymmetries that are observed both in experiment and in 2D edge fluid codes. Since the total number of charged particles is much greater in the CFR than in PFR, divertor asymmetries caused by the E x B drift should be attributed primarily to particle sources in the CFR caused by radial E x B drift., For complete list of authors see http://dx.doi.org/10.1088/0741-3335/57/9/095002
Published: 2015
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310. Key impact of finite-beta and fast ions in core and edge tokamak regions for the transition to advanced scenarios

Author: Garcia, J., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Garcia, J., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: Extensive linear and non-linear gyrokinetic simulations and linear magnetohydrodynamic (MHD) analyses performed for JET hybrid discharges with improved confinement have shown that the large population of fast ions found in the plasma core under particular heating conditions has a strong impact on core microturbulence and edge MHD by reducing core ion heat fluxes and increasing pedestal pressure in a feedback mechanism. In the case of the ITER like wall, it is shown how this mechanism plays a decisive role for the transition to plasma regimes with improved confinement and it can explain the weak power degradation obtained in dedicated power scans. The mechanism is found to be highly dependent on plasma triangularity as it changes the balance between the improvement in the plasma core and the edge. The feedback mechanism can play a similar role in the ITER hybrid scenario as in the JET discharges analysed due to its high triangularity plasmas and the large amount of fast ions generated in the core by the heating systems and the alpha power., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/5/053007
Published: 2015
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311. Comparative analysis of core heat transport of JET high density H-mode plasmas in carbon wall and ITER-like wall

Author: Kim, Hyun-Tae, Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Kim, Hyun-Tae, Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: A consistent deterioration of global confinement in H-mode experiments has been observed in JET [1] following the replacement of all carbon plasma facing components (PFCs) with an all metal ('ITER-like') wall (ILW). This has been correlated to the observed degradation of the pedestal confinement, as lower electron temperature (T-e) values are routinely measured at the top of the edge barrier region. A comparative investigation of core heat transport in JET-ILW and JET-CW (carbon wall) discharges has been performed, to assess whether core confinement has also been affected by the wall change. The results presented here have been obtained by analysing a set of discharges consisting of high density JET-ILW H-mode plasmas and comparing them against their counterpart discharges in JET-CW having similar global operational parameters. The set contains 10 baseline (beta(N) = 1. 5 similar to 2) discharge-pairs with 2.7 T toroidal magnetic field, 2.5 MA plasma current, and 14 to 17 MW of neutral beam injection (NBI) heating. Based on a T-e profile analysis using high resolution Thomson scattering (HRTS) data, the T-e profile peaking (i.e. core T-e (rho = 0.3)/edge T-e (rho = 0.7)) is found to be similar, and weakly dependent on edge T-e, for both JET-ILW and JET-CW discharges. When ILW discharges are seeded with N-2, core and edge T-e both increase to maintain a similar peaking factor. The change in core confinement is addressed with interpretative TRANSP simulations. It is found that JET-ILW H-mode plasmas have higher NBI power deposition to electrons and lower NBI power deposition to ions as compared to the JET-CW counterparts. This is an effect of the lower electron temperature at the top of the pedestal. As a result, the core electron energy confinement time is reduced in JET-ILW discharges, but the core ion energy confinement time is not decreased. Overall, the core energy confinement is found to be the same in the JET-ILW discharges compared to the JET-CW counterparts., For complete list of authors see http://dx.doi.org/10.1088/0741-3335/57/6/065002
Published: 2015
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312. Conceptual Design Of The Mechanical Tritium Pumping System For Jet Dte2

Author: Giegerich, Thomas, Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Giegerich, Thomas, Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: This paper describes the conceptual design of the Mechanical Tritium Pumping System (MTPS) that shall be installed and tested at JET during the next Deuterium-Tritium-Experiment (DTE2). This pump train uses a two-stage liquid ring pump in combination with a booster pump to cover a pressure regime from 10(-1) Pa to 10(5) Pa. As working fluid for all pumps, mercury will be used for tritium compatibility reasons. Starting from the requirements to MTPS, the pumps and their arrangement will be described in this paper as well as the mercury containment strategy and safety- and control issues., For complete list of authors see http://dx.doi.org/10.13182/FST14-950
Published: 2015
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313. WALLDYN simulations of global impurity migration in JET and extrapolations to ITER

Author: Schmid, K., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Schmid, K., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: The migration of first wall material due to erosion, plasma transport and re-deposition is one of the key challenges in current and future fusion devices. To predict erosion/re-deposition patterns and to understand the underlying principal processes, the global simulation code WallDYN was developed. It couples the evolution of the first wall surface composition to plasma impurity transport. To benchmark the WallDYN model, it was applied to the JET ITER-like wall experiment (JET-ILW), which mimics the ITER first wall material configuration and is thus an ideal environment to validate the predictive significance of WallDYN calculations for ITER application. The WallDYN calculations show good agreement with the Be deposition patterns determined from JET-ILWpost-campaign wall tile analysis. The WallDYN results on W erosion and deposition also qualitatively match the post mortem patterns but quantitatively fall short by a factor of 20 which can be consolidated by including the influence of ELMs on the W erosion source. Applying the same model and process physics as for the JET calculations, the impurity migration and resulting fuel species co-deposition in ITER for different wall configurations and background plasmas were calculated. The simulations show that C containing wall configurations lead to unacceptable T retention whereas for the current ITER material choice (Be wall and W divertor) co-deposition will not limit the ITER operation. However the erosion of W by self-sputtering even without the contribution of ELMs could hamper ITER operation under certain plasma scenarios., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/5/053015
Published: 2015
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314. Integrated core-SOL-divertor modelling for ITER including impurity : effect of tungsten on fusion performance in H-mode and hybrid scenario

Author: Zagorski, R., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Zagorski, R., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: The compatibility of two operational constraints-operation above the L-H power threshold and at low power to divertor-is examined for ITER long pulse H-mode and hybrid scenarios in integrated core-scrape off layer (SOL)-divertor modelling including impurities (intrinsic Be, He, Wand seeded Ne). The core thermal, particle and momentum transport is simulated with the GLF23 transport model tested in the self-consistent simulations of temperatures, density and toroidal rotation velocity in JET hybrid discharges and extrapolated to ITER. The beneficial effect of toroidal rotation velocity on fusion gain is shown. The sensitivity studies with respect to operational (separatrix and pedestal density, Ne gas puff) and unknown physics (W convective velocity and perpendicular diffusion in SOL as well as W prompt re-deposition) parameters are performed to determine their influence on the operational window and fusion gain., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/5/053032
Published: 2015
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315. The impact of poloidal asymmetries on tungsten transport in the core of JET H-mode plasmas

Author: Angioni, C., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Angioni, C., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: Recent progress in the understanding and prediction of the tungsten behaviour in the core of JET H-mode plasmas with ITER-like wall is presented. Particular emphasis is given to the impact of poloidal asymmetries of the impurity density. In particular, it is shown that the predicted reduction of temperature screening induced by the presence of low field side localization of the tungsten density produced by the centrifugal force is consistent with the observed tungsten behaviour in a JET discharge in H-mode baseline scenario. This provides first evidence of the role of poloidal asymmetries in reducing the strength of temperature screening. The main differences between plasma parameters in JET baseline and hybrid scenario discharges which affect the impact of poloidally asymmetric density on the tungsten radial transport are identified. This allows the conditions by which tungsten accumulation can be avoided to be more precisely defined., For complete list of authors see http://dx.doi.org/10.1063/1.4919036
Published: 2015
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316. Three-dimensional non-linear magnetohydrodynamic modeling of massive gas injection triggered disruptions in JET

Author: Fil, A., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Fil, A., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: JOREK 3D non-linear MHD simulations of a D-2 Massive Gas Injection (MGI) triggered disruption in JET are presented and compared in detail to experimental data. The MGI creates an overdensity that rapidly expands in the direction parallel to the magnetic field. It also causes the growth of magnetic islands (m/n = 2/1 and 3/2 mainly) and seeds the 1/1 internal kink mode. O-points of all island chains (including 1/1) are located in front of the MGI, consistently with experimental observations. A burst of MHD activity and a peak in plasma current take place at the same time as in the experiment. However, the magnitude of these two effects is much smaller than in the experiment. The simulated radiation is also much below the experimental level. As a consequence, the thermal quench is not fully reproduced. Directions for progress are identified. Radiation from impurities is a good candidate. (C) 2015 AIP Publishing LLC., For complete list of authors see http://dx.doi.org/10.1063/1.4922846
Published: 2015
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317. Beryllium migration in JET ITER-like wall plasmas

Author: Brezinsek, S., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Brezinsek, S., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: JET is used as a test bed for ITER, to investigate beryllium migration which connects the lifetime of first-wall components under erosion with tokamak safety, in relation to long-term fuel retention. The (i) limiter and the (ii) divertor configurations have been studied in JET-ILW (JET with a Be first wall and W divertor), and compared with those for the former JET-C (JET with carbon-based plasma-facing components (PFCs)). (i) For the limiter configuration, the Be gross erosion at the contact point was determined in situ by spectroscopy as between 4% (E-in = 35 eV) and more than 100%, caused by Be self-sputtering (E-in = 200 eV). Chemically assisted physical sputtering via BeD release has been identified to contribute to the effective Be sputtering yield, i.e. at E-in = 75 eV, erosion was enhanced by about 1/3 with respect to the bare physical sputtering case. An effective gross yield of 10% is on average representative for limiter plasma conditions, whereas a factor of 2 difference between the gross erosion and net erosion, determined by post-mortem analysis, was found. The primary impurity source in the limiter configuration in JET-ILW is only 25% higher (in weight) than that for the JET-C case. The main fraction of eroded Be stays within the main chamber. (ii) For the divertor configuration, neutral Be and BeD from physically and chemically assisted physical sputtering by charge exchange neutrals and residual ion flux at the recessed wall enter the plasma, ionize and are transported by scrape-off layer flows towards the inner divertor where significant net deposition takes place. The amount of Be eroded at the first wall (21 g) and the Be amount deposited in the inner divertor (28 g) are in fair agreement, though the balancing is as yet incomplete due to the limited analysis of PFCs. The primary impurity source in the JET-ILW is a factor of 5.3 less in comparison with that for JET-C, resulting in lower divertor material deposition, by more than one order of magni, For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/6/063021
Published: 2015
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318. Free boundary equilibrium in 3D tokamaks with toroidal rotation

Author: Cooper, W. A., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Cooper, W. A., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: The three-dimensional VMEC equilibrium solver has been adapted to numerically investigate the approximate toroidal rotation model we have derived. We concentrate our applications on the simulation of JET snakes and MAST long-lived modes under free boundary conditions. Helical core solutions are triggered when exceeds a threshold value, typically 2.7% in JET-like plasmas. A large plasma current and edge bootstrap current can drive helical core formations at arbitrarily small in which the ideal saturated internal kink coexists with an ideal saturated external kink structure of opposite phase. The centrifugal force linked with the rotation has the effect of displacing the plasma column away from the major axis, but does not alter significantly the magnitude of the edge corrugation of the plasma. Error field correction coil currents in JET-like configurations increase the outer midplane distortions by 2 cm. The edge bootstrap current enhances the edge modulation of the plasma driven by the core snake deformations in MAST., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/6/063032
Published: 2015
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319. WEST Physics Basis

Author: Bourdelle, C., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Bourdelle, C., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: With WEST (Tungsten Environment in Steady State Tokamak) (Bucalossi et al 2014 Fusion Eng. Des. 89 907-12), the Tore Supra facility and team expertise (Dumont et al 2014 Plasma Phys. Control. Fusion 56 075020) is used to pave the way towards ITER divertor procurement and operation. It consists in implementing a divertor configuration and installing ITER-like actively cooled tungsten monoblocks in the Tore Supra tokamak, taking full benefit of its unique long-pulse capability. WEST is a user facility platform, open to all ITER partners. This paper describes the physics basis of WEST: the estimated heat flux on the divertor target, the planned heating schemes, the expected behaviour of the L-H threshold and of the pedestal and the potential W sources. A series of operating scenarios has been modelled, showing that ITER-relevant heat fluxes on the divertor can be achieved in WEST long pulse H-mode plasmas., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/6/063017
Published: 2015
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320. L to H mode transition : parametric dependencies of the temperature threshold

Author: Bourdelle, C., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Bourdelle, C., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: The L to H mode transition occurs at a critical power which depends on various parameters, such as the magnetic field, the density, etc. Experimental evidence on various tokamaks (JET, ASDEX-Upgrade, DIII-D, Alcator C-Mod) points towards the existence of a critical temperature characterizing the transition. This criterion for the L-H transition is local and is therefore easier to be compared to theoretical approaches. In order to shed light on the mechanisms of the transition, simple theoretical ideas are used to derive a temperature threshold (T-th). They are based on the stabilization of the underlying turbulence by a mean radial electric field shear. The nature of the turbulence varies as the collisionality decreases, from resistive ballooning modes to ion temperature gradient and trapped electron modes. The obtained parametric dependencies of the derived T-th are tested versus magnetic field, density, effective charge. Various robust experimental observations are reproduced, in particular T-th increases with magnetic field B and increases with density below the density roll-over observed on the power threshold., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/7/073015
Published: 2015
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321. Turbulent transport analysis of JET H-mode and hybrid plasmas using QuaLiKiz and Trapped Gyro Landau Fluid

Author: Baiocchi, B., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Baiocchi, B., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: The physical transport processes at the basis of JET typical inductive H-mode scenarios and advanced hybrid regimes, with improved thermal confinement, are analyzed by means of some of the newest and more sophisticated quasi-linear transport models: trapped gyro Landau fluid (TGLF) and QuaLiKiz. The temporal evolution of JET pulses is modelled by CRONOS where the turbulent transport is modelled by either QuaLiKiz or TGLF. Both are first principle models with a more comprehensive physics than the models previously developed and therefore allow the analysis of the physics at the basis of the investigated scenarios. For H-modes, ion temperature gradient (ITG) modes are found to be dominant and the transport models are able to properly reproduce temperature profiles in self-consistent simulations. However, for hybrid regimes, in addition to ITG trapped electron modes (TEM) are also found to be important and different physical mechanisms for turbulence reduction play a decisive role. Whereas E x B flow shear and plasma geometry have a limited impact on turbulence, the presence of a large population of fast ions, quite important in low density regimes, can stabilize core turbulence mainly when the electromagnetic effects are taken into account. The TGLF transport model properly captures these mechanisms and correctly reproduces temperatures., For complete list of authors see http://dx.doi.org/10.1088/0741-3335/57/3/035003
Published: 2015
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322. Plasma isotopic changeover experiments in JET under carbon and ITER-like wall conditions

Author: Loarer, T., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Loarer, T., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: In JET-ILWisotopic plasma wall changeover experiments have been carried out to determine the amount of particles accessible by changing the plasma from H to D and from D to H. The gas balance analysis integrated over the experimental sessions show that the total amount of H or D removed from the wall is in the range of (1-3) x 10(22)D. For both changeover experiments, the respective plasma isotopic ratio behaviour is exactly the same as a function of the pulse number. After only 80 s of plasma (4 pulses), the plasma isotopic ratio is lower than 10%, below 4.5% after 13 pulses and then saturates around similar to 2-3%. In these conditions, the removal efficiency through plasma operation becomes very poor. The saturation of the plasma isotopic ratio in the range of 10% is also observed for the JET-C configuration although the amount of tritium retained in the vessel after the DT pulses was more than one order of magnitude compared to the retention observed with the JET-ILW. This demonstrates that the amount of particle recovery through plasma changeover is independent from the long term retention. Since this long term reservoir results from codeposition, these experiments suggest that there is a limited access to these codeposited particles by plasma isotopic changeover. Finally, in ITER, change over from D/T to H at the end of the discharge for possibly reducing the long term retention does not appear as a good strategy., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/4/043021
Published: 2015
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323. Improved confinement in JET high beta plasmas with an ITER-like wall

Author: Challis, C. D., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Challis, C. D., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: The replacement of the JET carbon wall (C-wall) by a Be/W ITER-like wall (ILW) has affected the plasma energy confinement. To investigate this, experiments have been performed with both the C-wall and ILW to vary the heating power over a wide range for plasmas with different shapes. It was found that the power degradation of thermal energy confinement was weak with the ILW; much weaker than the IPB98(y,2) scaling and resulting in an increase in normalized confinement from H-98 similar to 0.9 at beta(N) similar to 1.5 to H-98 similar to 1.2 - 1.3 at beta(N) similar to 2.5 - 3.0 as the power was increased (where H-98 = tau(E)/tau(IPB98(y, 2)) and beta(N) = beta B-T(T)/aI(P) in %T/mMA). This reproduces the general trend in JET of higher normalized confinement in the so-called 'hybrid' domain, where normalized beta is typically above 2.5, compared with 'baseline' ELMy H-mode plasmas with beta(N) similar to 1.5-2.0. This weak power degradation of confinement, which was also seen with the C-wall experiments at low triangularity, is due to both increased edge pedestal pressure and core pressure peaking at high power. By contrast, the high triangularity C-wall plasmas exhibited elevated H-98 over a wide power range with strong, IPB98(y,2)-like, power degradation. This strong power degradation of confinement appears to be linked to an increase in the source of neutral particles from the wall as the power increased, an effect that was not reproduced with the ILW. The reason for the loss of improved confinement domain at low power with the ILW is yet to be clarified, but contributing factors may include changes in the rate of gas injection, wall recycling, plasma composition and radiation. The results presented in this paper show that the choice of wall materials can strongly affect plasma performance, even changing confinement scalings that are relied upon for extrapolation to future devices., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/5/053031
Published: 2015
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324. Runaway electron beam generation and mitigation during disruptions at JET-ILW

Author: Reux, C., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Reux, C., Andersson Sundén, Erik, Militello Asp, Emilia, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: Disruptions are a major operational concern for next generation tokamaks, including ITER. They may generate excessive heat loads on plasma facing components, large electromagnetic forces in the machine structures and several MA of multi-MeV runaway electrons. A more complete understanding of the runaway generation processes and methods to suppress them is necessary to ensure safe and reliable operation of future tokamaks. Runaway electrons were studied at JET-ILW showing that their generation dependencies (accelerating electric field, avalanche critical field, toroidal field, MHD fluctuations) are in agreement with current theories. In addition, vertical stability plays a key role in long runaway beam formation. Energies up to 20 MeV are observed. Mitigation of an incoming runaway electron beam triggered by massive argon injection was found to be feasible provided that the injection takes place early enough in the disruption process. However, suppressing an already accelerated runaway electron beam in the MA range was found to be difficult even with injections of more than 2 kPa.m(3) high-Z gases such as krypton or xenon. This may be due to the presence of a cold background plasma weakly coupled to the runaway electron beam which prevents neutrals from penetrating in the electron beam core. Following unsuccessful mitigation attempts, runaway electron impacts on beryllium plasma-facing components were observed, showing localized melting with toroidal asymmetries., For complete list of authors see http://dx.doi.org/10.1088/0029-5515/55/9/093013
Published: 2015
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325. The effects of impurities and core pressure on pedestal stability in Joint European Torus (JET)

Author: Saarelma, S., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, Zychor, I., Saarelma, S., Andersson Sundén, Erik, Militello Asp, Elina, Binda, Federico, Cecconello, Marco, Conroy, Sean, Dzysiuk, Natalia, Ericsson, Göran, Eriksson, Jacob, Hellesen, Carl, Hjalmarsson, Anders, Possnert, Göran, Sjöstrand, Henrik, Skiba, Mateusz, Weiszflog, Matthias, and Zychor, I.
Abstract: The H-mode pedestal plays an important role in determining global confinement in tokamaks. In high triangularity H-mode experiments in Joint European Torus with the ITER-like wall (JET-ILW), significantly higher pedestal temperature and global confinement have been achieved with nitrogen seeding. The experimentally observed increase in pedestal height is inconsistent with the stability calculations using the experimental profiles. Numerically, we find that the consistency with stability improvement can be restored if we assume a shift of the pedestal inwards and increased ion dilution due to the impurity seeding. Significantly better confinement and pedestal height have been observed in JET-ILW plasmas when the core pressure is increased. The enhanced pedestal height can be linked to an improvement in edge stability arising from an increase in the Shafranov-shift, higher edge current, and pedestal widening in flux space., For complete list of authors see http://dx.doi.org/10.1063/1.4921413
Published: 2015
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326. Overview of the JET results

Author: Romanelli, F., Abhangi, M., Abreu, P., Aftanas, M., Afzal, M., Aggarwal, K. M., Aho-Mantila, L., Ahonen, E., Aints, M., Airila, M., Albanese, R., Alegre, D., Alessi, E., Aleynikov, P., Alfier, A., Alkseev, A., Allan, P., Almaviva, S., Alonso, A., Alper, B., Alsworth, I., Alves, D., Ambrosino, G., Ambrosino, R., Amosov, V., Andersson, F., Andersson Sundén, Erik, Angelone, M., Anghel, A., Anghel, M., Angioni, C., Appel, L., Apruzzese, G., Arena, P., Ariola, M., Arnichand, H., Arnoux, G., Arshad, S., Ash, A., Asp, E., Asunta, O., Atanasiu, C. V., Austin, Y., Avotina, L., Axton, M. D., Ayres, C., Bachmann, C., Baciero, A., Baiao, D., Bailescu, V., Baiocchi, B., Baker, A., Baker, R. A., Balboa, I., Balden, M., Balshaw, N., Bament, R., Banks, J. W., Baranov, Y. F., Barlow, I. L., Barnard, M. A., Barnes, D., Barnsley, R., Baron Wiechec, A., Baruzzo, M., Basiuk, V., Bassan, M., Bastow, R., Batista, A., Batistoni, P., Bauer, R., Bauvir, B., Bazylev, B., Beal, J., Beaumont, P. S., Becoulet, A., Bednarczyk, P., Bekris, N., Beldishevski, M., Bell, K., Belli, F., Bellinger, M., Belo, J. K., Belo, P., Belonohy, E., Benterman, N. A., Bergsaker, H., Bernardo, J., Bernert, M., Berry, M., Bertalot, L., Beurskens, M. N. A., Bieg, B., Bielecki, J., Biewer, T., Bigi, M., Bilkova, P., Binda, Federico, Bizarro, J. P. S., Bjorkas, C., Blackman, K., Blackman, T. R., Blanchard, P., Blanco, E., Blatchford, P., Bobkov, V., Boboc, A., Bodnar, G., Bogar, O., Bolzonella, T., Boncagni, L., Bonham, R., Bonheure, G., Boom, J., Booth, J., Borba, D., Borodin, D., Botrugno, A., Boulbe, C., Boulting, P., Bovert, K. V., Bowden, M., Bower, C., Boyce, T., Boyer, H. J., Bradshaw, J. M. A., Braic, V., Breizman, B., Bremond, S., Brennan, P. D., Brett, A., Brezinsek, S., Bright, M. D. J., Brix, M., Broeckx, W., Brombin, M., Brown, B. C., Brown, D. P. D., Brown, M., Bruno, E., Bucalossi, J., Buch, J., Buckley, M. A., Bucko, K., Budny, R., Bufferand, H., Bulman, M., Bulmer, N., Bunting, P., Buratti, P., Burcea, G., Burckhart, A., Buscarino, A., Butcher, P. R., Butler, N. K., Bykov, I., Byrne, J., Byszuk, A., Cackett, A., Cahyna, P., Cain, G., Calabro, G., Callaghan, C. P., Campling, D. C., Cane, J., Cannas, B., Capel, A. J., Caputano, M., Card, P. J., Cardinali, A., Carman, P., Carralero, D., Carraro, L., Carvalho, B. B., Carvalho, I., Carvalho, P., Casson, F. J., Castaldo, C., Cavazzana, R., Cavinato, M., Cazzaniga, A., Cecconello, Marco, Cecil, E., Cenedese, A., Centioli, C., Cesario, R., Challis, C. D., Chandler, M., Chandra, D., Chang, C. S., Chankin, A., Chapman, I. T., Chapman, S. C., Chernyshova, M., Chiru, P., Chitarin, G., Chouli, B., Chung, N., Ciraolo, G., Ciric, D., Citrin, J., Clairet, F., Clark, E., Clatworthy, D., Clay, R., Clever, M., Coad, J. P., Coates, P. A., Coccorese, V., Cocilovo, V., Coda, S., Coelho, R., Coenen, J. W., Coffey, I., Colas, L., Collins, S., Conboy, J. E., Conroy, Sean, Cook, N., Coombs, D., Cooper, D., Cooper, S. R., Corre, Y., Corrigan, G., Cortes, S., Coster, D., Couchman, A. S., Cox, M., Cox, M. P., Cox, P., Craciunescu, T., Cramp, S., Crisanti, F., Cristescu, I., Croci, G., Croft, O., Crombe, K., Crowe, R., Cruz, N., Cseh, G., Cull, K., Cupido, L., Curran, D., Curuia, M., Czarnecka, A., Czarski, T., Dalley, S., Dalziel, A., Darrow, D., Davies, R., Davis, W., Day, C., Day, I. E., de la Cal, E., de la Luna, E., De Magistris, M., de Pablos, J. L., De Tommasi, G., de Vries, P. C., Deakin, K., Deane, J., Decker, J., Degli Agostini, F., Dejarnac, R., Delabie, E., den Harder, N., Dendy, R. O., Denner, P., Devaux, S., Devynck, P., Di Maio, F., Di Pace, L., Dittmar, T., Dodt, D., Donne, T., Dooley, P., Dorling, S. E., Dormido-Canto, S., Doswon, S., Douai, D., Doyle, P. T., Dreischuh, T., Drewelow, P., Drozdov, V., Drozdowicz, K., Dumont, R., Dumortier, P., Dunai, D., Dunne, M., Duran, I., Durodie, F., Dutta, P., Duval, B., Dux, R., Dylst, K., Dzysiuk, N., Edappala, P. V., Edwards, A. M., Eich, Th., Ekedahl, A., Elevant, T., El-Jorf, R., Elsmore, C. G., Ericsson, Göran, Eriksson, A., Eriksson, Jacob, Eriksson, L. G., Esposito, B., Esser, H. G., Esteve, D., Evans, G. E., Evans, J., Ewart, G. D., Ewers, D. T., Fagan, D., Falie, D., Farthing, J. W., Fasoli, A., Fattorini, L., Faugeras, B., Faustin, J., Fawlk, N., Federici, G., Fedorczak, N., Felton, R. C., Fenzi, C., Fernades, A., Fernandes, H., Ferreira, J., Fessey, J. A., Figini, L., Figueiredo, A., Figueiredo, J., Fil, A., Finburg, P., Firdaouss, M., Fischer, U., Fittill, L., Fitzgerald, M., Flammini, D., Flanagan, J., Fleming, C., Flinders, K., Formisano, A., Forsythe, L., Fortuna, L., Fortune, M., Frasca, M., Frassinetti, L., Freisinger, M., Fresa, R., Frigione, D., Fuchs, V., Fyvie, J., Gadomska, M., Gal, K., Galperti, C., Galvao, R., Gao, X., Garavaglia, S., Garcia, J., Garcia-Carrasco, A., Garcia-Munoz, M., Gardner, M., Garzotti, L., Gaudio, P., Gauthier, E., Gaze, J. W., Gear, D. F., Gee, S. J., Gelfusa, M., Genangeli, E., Gerasimov, S., Gervasini, G., Ghate, M., Gherendi, M., Giacalone, J. C., Giacomelli, L., Gibson, C. S., Giegerich, T., Gin, D., Giovannozzi, E., Girardo, J. B., Giroud, C., Giruzzi, G., Gleason-Gonzalez, C., Godwin, J., Gohil, P., Gojska, A., Goloborod'ko, V., Gomes, R., Goncalves, B., Goniche, M., Gonzalez, S., Goodsell, B., Goodyear, A., Gorini, G., Goussarov, A., Graham, B., Graham, M. E., Graves, J., Grazier, N., Green, N. R., Greuner, H., Grigore, E., Griph, F. S., Grisolia, C., Grist, D., Groth, M., Grundy, C. N., Gryaznevich, M., Guard, D., Gubb, D., Guillemaut, C., Guo, Y., Utoh, H. H., Hackett, L. J., Hacquin, S., Hagar, A., Hakola, A., Halitovs, M., Hall, S. J., Hallworth Cook, S. P., Hammond, K., Hart, J., Harting, D., Hartmann, N., Haupt, T. D. V., Hawkes, N. C., Hawkins, J., Haydon, P. W., Hazel, S., Heesterman, P. J. L., Heinola, K., Hellesen, Carl, Hellsten, T., Helou, W., Hemming, O. N., Hender, T. C., Henderson, M., Henriques, R., Hepple, D., Hermon, G., Hidalgo, C., Highcock, E. G., Hill, J. W., Hill, M., Hillairet, J., Hillesheim, J., Hillis, D., Hjalmarsson, Anders, Hobirk, J., Hogben, C. H. A., Hogeweij, G. M. D., Homfray, D. A., Horacek, J., Horton, A. R., Horton, L. D., Hotchin, S. P., Hough, M. R., Howarth, P. J., Huber, A., Huddleston, T. M., Hughes, M., Hunter, C. L., Hurzlmeier, H., Huygen, S., Huynh, P., Igitkhanov, J., Iglesias, D., Imrisek, M., Ivanova, D., Ivanova-Stanik, I., Ivings, E., Jachmich, S., Jacobsen, A. S., Jacquet, P., Jakubowska, K., James, J., Janky, F., Jarvinen, A., Jaulmes, F., Jednorog, S., Jenkins, C., Jenkins, I., Jesko, K., Joffrin, E., Johnson, R., Johnson, T., Joita, L., Jones, G., Jones, T. T. C., Joyce, L., Jupen, C., Hoshino, K. K., Kallenbach, A., Kalupin, D., Kamiya, K., Kaniewski, J., Kantor, A., Karhunen, J., Kasprowicz, G., Kaveney, G., Kazakov, Y., Keeling, D. L., Keep, J., Kempenaars, M., Kennedy, C., Kenny, D., Khilkevich, E., Kiisk, M., Kim, H. -T, Kim, H. S., King, C., King, D., King, R. F., Kinna, D. J., Kiptily, V., Kirov, K., Kirschner, A., Kizane, G., Klepper, C., Knaup, M., Knipe, S. J., Kobuchi, T., Kochl, F., Kocsis, G., Kogut, D., Koivuranta, S., Koppen, M., Koskela, T., Koslowski, H. R., Kotov, V., Kowalska-Strzeciwilk, E., Krasilnikov, A., Krasilnikov, V., Kreter, A., Krieger, K., Krivchenkov, Y., Krivska, A., Kruezi, U., Ksiazek, I., Kukushkin, A., Kundu, A., Kurki-Suonio, T., Kwon, O. T., Kyrytsya, V., Laan, M., Labate, C., Laguardia, L., Lam, N., Lane, C., Lang, P. T., Lapins, J., Lasa, A., Last, J. R., Lawson, A., Lawson, K. D., Lazaros, A., Lazzaro, E., Lee, S., Leggate, H. J., Lehnen, M., Leichtle, D., Leichuer, P., Leipold, F., Lengar, I., Lennholm, M., Lerche, E., Leyland, M., Leysen, W., Liang, Y., Likonen, J., Lindholm, V., Linke, J., Linsmeier, Ch., Lipschultz, B., Litaudon, X., Liu, G., Liu, Y., Lo Schiavo, V. P., Loarer, T., Loarte, A., Lobel, R. C., Lohr, N., Lomas, P. J., Lonnroth, J., Lopez, J., Lopez, J. M., Louche, F., Loving, A. B., Lowbridge, S., Lowry, C., Luce, T., Lucock, R. M. A., Lukin, A., Lungu, A. M., Lungu, C. P., Lupelli, I., Lyssoivan, A., Macheta, P., Mackenzie, A. S., Maddaluno, G., Maddison, G. P., Magesh, B., Maget, P., Maggi, C. F., Maier, H., Mailloux, J., Maj, A., Makkonen, T., Makwana, R., Malaquias, A., Mansffield, F., Mansfield, M., Manso, M. E., Mantica, P., Mantsinen, M., Manzanares, A., Marandet, Y., Marcenko, N., Marchetto, C., Marchuk, O., Marinelli, M., Marinucci, M., Markovic, T., Marocco, D., Marot, L., Marren, C. A., Marsen, S., Marshal, R., Martin, A., Martin, D. L., Martin, Y., Martin de Aguilera, A., Martin-Solis, J. R., Masiello, A., Maslov, M., Maslova, V., Matejcik, S., Mattei, M., Matthews, G. F., Matveev, D., Matveev, M., Maviglia, F., Mayer, M., Mayoral, M. -L, Mazon, D., Mazzotta, C., McAdams, R., McCarthy, P. J., McClements, K. G., McCormick, K., McCullen, P. A., McDonald, D., Mcgregor, R., McKean, R., McKehon, J., McKinley, R., Meadows, I., Meadows, R. C., Medina, F., Medland, M., Medley, S., Meigh, S., Meigs, A. G., Meneses, L., Menmuir, S., Merrigan, I. R., Mertens, Ph., Meshchaninov, S., Messiaen, A., Meszaros, B., Meyer, H., Miano, G., Michling, R., Middleton-Gear, D., Miettunen, J., Migliucci, P., Militello-Asp, E., Minucci, S., Mirizzi, F., Miyoshi, Y., Mlynar, J., Monakhov, I., Monier-Garbet, P., Mooney, R., Moradi, S., Mordijck, S., Moreira, L., Moreno, R., Morgan, P. D., Morgan, R., Morley, L., Morlock, C., Morris, A. W., Morris, J., Moser, L., Moulton, D., Murari, A., Muraro, A., Mustata, I., Asakura, N. N., Nabais, F., Nakano, T., Nardon, E., Naulin, V., Nave, M. F. F., Nedzelski, I., Neethiraj, N., Nemtsev, G., Nespoli, F., Neto, A., Neu, R., Neubauer, O., Newman, M., Nicholls, K. J., Nicolai, D., Nicolas, T., Nieckchen, P., Nielsen, P., Nightingale, M. P. S., Nilsson, E., Nishijima, D., Noble, C., Nocente, M., Nodwell, D., Nordman, H., Nunes, I., O'Meara, B., Oberkofler, M., Obryk, B., Odupitan, T., Ogawa, M. T., O'Gorman, T., Okabayashi, M., Olariu, S., O'Mullane, M., Ongena, J., Orsitto, F., Oswuigwe, B. 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J., Castaldo, C., Cavazzana, R., Cavinato, M., Cazzaniga, A., Cecconello, Marco, Cecil, E., Cenedese, A., Centioli, C., Cesario, R., Challis, C. D., Chandler, M., Chandra, D., Chang, C. S., Chankin, A., Chapman, I. T., Chapman, S. C., Chernyshova, M., Chiru, P., Chitarin, G., Chouli, B., Chung, N., Ciraolo, G., Ciric, D., Citrin, J., Clairet, F., Clark, E., Clatworthy, D., Clay, R., Clever, M., Coad, J. P., Coates, P. A., Coccorese, V., Cocilovo, V., Coda, S., Coelho, R., Coenen, J. W., Coffey, I., Colas, L., Collins, S., Conboy, J. E., Conroy, Sean, Cook, N., Coombs, D., Cooper, D., Cooper, S. R., Corre, Y., Corrigan, G., Cortes, S., Coster, D., Couchman, A. S., Cox, M., Cox, M. P., Cox, P., Craciunescu, T., Cramp, S., Crisanti, F., Cristescu, I., Croci, G., Croft, O., Crombe, K., Crowe, R., Cruz, N., Cseh, G., Cull, K., Cupido, L., Curran, D., Curuia, M., Czarnecka, A., Czarski, T., Dalley, S., Dalziel, A., Darrow, D., Davies, R., Davis, W., Day, C., Day, I. E., de la Cal, E., de la Luna, E., De Magistris, M., de Pablos, J. L., De Tommasi, G., de Vries, P. C., Deakin, K., Deane, J., Decker, J., Degli Agostini, F., Dejarnac, R., Delabie, E., den Harder, N., Dendy, R. O., Denner, P., Devaux, S., Devynck, P., Di Maio, F., Di Pace, L., Dittmar, T., Dodt, D., Donne, T., Dooley, P., Dorling, S. E., Dormido-Canto, S., Doswon, S., Douai, D., Doyle, P. T., Dreischuh, T., Drewelow, P., Drozdov, V., Drozdowicz, K., Dumont, R., Dumortier, P., Dunai, D., Dunne, M., Duran, I., Durodie, F., Dutta, P., Duval, B., Dux, R., Dylst, K., Dzysiuk, N., Edappala, P. V., Edwards, A. M., Eich, Th., Ekedahl, A., Elevant, T., El-Jorf, R., Elsmore, C. G., Ericsson, Göran, Eriksson, A., Eriksson, Jacob, Eriksson, L. G., Esposito, B., Esser, H. G., Esteve, D., Evans, G. E., Evans, J., Ewart, G. D., Ewers, D. T., Fagan, D., Falie, D., Farthing, J. W., Fasoli, A., Fattorini, L., Faugeras, B., Faustin, J., Fawlk, N., Federici, G., Fedorczak, N., Felton, R. C., Fenzi, C., Fernades, A., Fernandes, H., Ferreira, J., Fessey, J. A., Figini, L., Figueiredo, A., Figueiredo, J., Fil, A., Finburg, P., Firdaouss, M., Fischer, U., Fittill, L., Fitzgerald, M., Flammini, D., Flanagan, J., Fleming, C., Flinders, K., Formisano, A., Forsythe, L., Fortuna, L., Fortune, M., Frasca, M., Frassinetti, L., Freisinger, M., Fresa, R., Frigione, D., Fuchs, V., Fyvie, J., Gadomska, M., Gal, K., Galperti, C., Galvao, R., Gao, X., Garavaglia, S., Garcia, J., Garcia-Carrasco, A., Garcia-Munoz, M., Gardner, M., Garzotti, L., Gaudio, P., Gauthier, E., Gaze, J. W., Gear, D. F., Gee, S. J., Gelfusa, M., Genangeli, E., Gerasimov, S., Gervasini, G., Ghate, M., Gherendi, M., Giacalone, J. C., Giacomelli, L., Gibson, C. S., Giegerich, T., Gin, D., Giovannozzi, E., Girardo, J. B., Giroud, C., Giruzzi, G., Gleason-Gonzalez, C., Godwin, J., Gohil, P., Gojska, A., Goloborod'ko, V., Gomes, R., Goncalves, B., Goniche, M., Gonzalez, S., Goodsell, B., Goodyear, A., Gorini, G., Goussarov, A., Graham, B., Graham, M. E., Graves, J., Grazier, N., Green, N. R., Greuner, H., Grigore, E., Griph, F. S., Grisolia, C., Grist, D., Groth, M., Grundy, C. N., Gryaznevich, M., Guard, D., Gubb, D., Guillemaut, C., Guo, Y., Utoh, H. H., Hackett, L. J., Hacquin, S., Hagar, A., Hakola, A., Halitovs, M., Hall, S. J., Hallworth Cook, S. P., Hammond, K., Hart, J., Harting, D., Hartmann, N., Haupt, T. D. V., Hawkes, N. C., Hawkins, J., Haydon, P. W., Hazel, S., Heesterman, P. J. L., Heinola, K., Hellesen, Carl, Hellsten, T., Helou, W., Hemming, O. N., Hender, T. C., Henderson, M., Henriques, R., Hepple, D., Hermon, G., Hidalgo, C., Highcock, E. G., Hill, J. W., Hill, M., Hillairet, J., Hillesheim, J., Hillis, D., Hjalmarsson, Anders, Hobirk, J., Hogben, C. H. A., Hogeweij, G. M. 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P., Lupelli, I., Lyssoivan, A., Macheta, P., Mackenzie, A. S., Maddaluno, G., Maddison, G. P., Magesh, B., Maget, P., Maggi, C. F., Maier, H., Mailloux, J., Maj, A., Makkonen, T., Makwana, R., Malaquias, A., Mansffield, F., Mansfield, M., Manso, M. E., Mantica, P., Mantsinen, M., Manzanares, A., Marandet, Y., Marcenko, N., Marchetto, C., Marchuk, O., Marinelli, M., Marinucci, M., Markovic, T., Marocco, D., Marot, L., Marren, C. A., Marsen, S., Marshal, R., Martin, A., Martin, D. L., Martin, Y., Martin de Aguilera, A., Martin-Solis, J. R., Masiello, A., Maslov, M., Maslova, V., Matejcik, S., Mattei, M., Matthews, G. F., Matveev, D., Matveev, M., Maviglia, F., Mayer, M., Mayoral, M. -L, Mazon, D., Mazzotta, C., McAdams, R., McCarthy, P. J., McClements, K. G., McCormick, K., McCullen, P. A., McDonald, D., Mcgregor, R., McKean, R., McKehon, J., McKinley, R., Meadows, I., Meadows, R. C., Medina, F., Medland, M., Medley, S., Meigh, S., Meigs, A. G., Meneses, L., Menmuir, S., Merrigan, I. R., Mertens, Ph., Meshchaninov, S., Messiaen, A., Meszaros, B., Meyer, H., Miano, G., Michling, R., Middleton-Gear, D., Miettunen, J., Migliucci, P., Militello-Asp, E., Minucci, S., Mirizzi, F., Miyoshi, Y., Mlynar, J., Monakhov, I., Monier-Garbet, P., Mooney, R., Moradi, S., Mordijck, S., Moreira, L., Moreno, R., Morgan, P. D., Morgan, R., Morley, L., Morlock, C., Morris, A. W., Morris, J., Moser, L., Moulton, D., Murari, A., Muraro, A., Mustata, I., Asakura, N. N., Nabais, F., Nakano, T., Nardon, E., Naulin, V., Nave, M. F. F., Nedzelski, I., Neethiraj, N., Nemtsev, G., Nespoli, F., Neto, A., Neu, R., Neubauer, O., Newman, M., Nicholls, K. J., Nicolai, D., Nicolas, T., Nieckchen, P., Nielsen, P., Nightingale, M. P. S., Nilsson, E., Nishijima, D., Noble, C., Nocente, M., Nodwell, D., Nordman, H., Nunes, I., O'Meara, B., Oberkofler, M., Obryk, B., Odupitan, T., Ogawa, M. T., O'Gorman, T., Okabayashi, M., Olariu, S., O'Mullane, M., Ongena, J., Orsitto, F., Oswuigwe, B. I., Pace, N., Pacella, D., Page, A., Paget, A., Pagett, D., Pajuste, E., Palazzo, S., Pamela, J., Pamela, S., Panin, A., Panja, S., Papp, P., Parail, V., Paris, P., Parish, S. C. W., Park, M., Parsloe, A., Pasqualotto, R., Pearson, I. J., Pedrosa, M. A., Pereira, R., Perelli Cippo, E., Perez von Thun, Ch., Perez-Von-Thun, C., Pericoli-Ridolfini, V., Perona, A., Peruzzo, S., Peschanyi, S., Peterka, M., Petersson, P., Petravich, G., Petrzilka, V., Pfefferle, D., Philipps, V., Pietropaolo, A., Pillon, M., Pintsuk, G., Piovesan, P., Pires dos Reis, A., Pironti, A., Pisano, F., Pitts, R., Plusczyk, C., Plyusnin, V., Pomaro, N., Pompilian, O., Pool, P. J., Popovichev, S., Porcelli, F., Porosnicu, C., Porton, M., Pospieszczyk, A., Possnert, Göran, Potzel, S., Powell, T., Pozniak, K., Pozzi, J., Prajapati, V., Prakash, R., Prestopino, G., Price, D., Price, R., Prior, P., Prokopowicz, R., Proudfoot, R., Puglia, P., Puiatti, M. E., Pulley, D., Purahoo, K., Putterich, T., Quercia, A., Rachlew, E., Rack, M., Raeder, J., Rainford, M. S. J., Ramogida, G., Ranjan, S., Rasmussen, J., Rasmussen, J. J., Rathod, K., Ratta, G., Rayner, C., Rebai, M., Reece, D., Reed, A., Refy, D., Regan, B., Regana, J., Reich, M., Reid, P., Reinelt, M., Reinke, M. L., Reinke, M., Reiser, D., Reiter, D., Rendell, D., Reux, C., Riccardo, V., Rimini, F. G., Riva, M., Roberts, J. E. C., Robins, R. J., Robinson, S. A., Robinson, T., Robson, D. W., Roddick, P., Rodionov, R., Rohde, V., Romanelli, M., Romanelli, S., Romano, A., Rowe, D., Rowe, S., Rowley, A., Rubel, M., Rubinacci, G., Ruchko, L., Ruiz, M., Ruset, C., Ryc, L., Rzadkiewicz, J., Saarelma, S., Sabot, R., Sadakov, S., Safi, E., Sagar, P., Saibene, G., Saint-Laurent, F., Salewski, M., Salmi, A., Salzedas, F., Samm, U., Sandiford, D., Sandquist, P., Santa, P., Santala, M. I. K., Sartori, F., Sartori, R., Saunders, R., Sauter, O., Scannell, R., Scarabosio, A., Schlummer, T., Schmidt, V., Schmitz, O., Schmuck, S., Schneider, M., Scholz, M., Schopf, K., Schweer, B., Sergienko, G., Serikov, A., Sertoli, M., Shabbir, A., Shannon, M., Shannon, M. M. J., Sharapov, S. E., Shaw, I., Shaw, S. R., Shepherd, A., Shevelev, A., Shumack, A., Sibbald, M., Sieglin, B., Silva, C., Simmons, P. A., Sinha, A., Sipila, S. K., Sips, A. C. C., Siren, P., Sirinelli, A., Sjöstrand, Henrik, Skiba, Mateusz, Skilton, R., Slade, B., Smith, N., Smith, P. G., Smith, T. J., Snoj, L., Soare, S., Solano, E. R., Soldatov, S., Sonato, P., Sopplesa, A., Sousa, J., Sowden, C. B. C., Sozzi, C., Sparkes, A., Spelzini, T., Spineanu, F., Stables, G., Stamatelatos, I., Stamp, M. F., Stancalie, V., Stankiewicz, R., Stankunas, G., Stano, M., Stan-Sion, C., Starkey, D. E., Stead, M. J., Stejner, M., Stephen, A. V., Stephen, M., Stevens, B. 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P., Valcarcel, D., Valisa, M., Valovic, M., Van Eester, D., Van Renterghem, W., van Rooij, G. J., Varandas, C. A. F., Varoutis, S., Vartanian, S., Vasava, K., Vdovin, V., Vega, J., Verdoolaege, G., Verhoeven, R., Verona, C., Vervier, M., Veshchev, E., Vezinet, D., Vicente, J., Villari, S., Villone, F., Vinyar, I., Viola, B., Vitelli, R., Vitins, A., Vlad, M., Voitsekhovitch, I., Vondracek, P., Vrancken, M., Pires de Sa, W. W., Waldon, C. W. F., Walker, M., Walsh, M., Warren, R. J., Waterhouse, J., Watkins, N. W., Watts, C., Wauters, T., Way, M. W., Webster, A., Weckmann, A., Weiland, J., Weisen, H., Weiszflog, Matthias, Welte, S., Wendel, J., Wenninger, R., West, A. T., Wheatley, M. R., Whetham, S., Whitehead, A. M., Whitehead, B. D., Whittington, P., Widdowson, A. M., Wiesen, S., Wilkes, D., Wilkinson, J., Williams, M., Wilson, A. R., Wilson, D. J., Wilson, H. R., Wischmeier, M., Withenshaw, G., Witts, D. M., Wojciech, D., Wojenski, A., Wood, D., Wood, S., Woodley, C., Woznicka, U., Wright, J., Wu, J., Yao, L., Yapp, D., Yavorskij, V., Yoo, M. G., Yorkshades, J., Young, C., Young, D., Young, I. D., Zabolotny, W., Zacks, J., Zagorski, R., Zaitsev, F. S., Zanino, R., Zaroschi, V., Zastrow, K. D., Zeidner, W., Ziolkowski, A., Zoita, V., Zoletnik, S., and Zychor, I.
Abstract: Since the installation of an ITER-like wall, the JET programme has focused on the consolidation of ITER design choices and the preparation for ITER operation, with a specific emphasis given to the bulk tungsten melt experiment, which has been crucial for the final decision on the material choice for the day-one tungsten divertor in ITER. Integrated scenarios have been progressed with the re-establishment of long-pulse, high-confinement H-modes by optimizing the magnetic configuration and the use of ICRH to avoid tungsten impurity accumulation. Stationary discharges with detached divertor conditions and small edge localized modes have been demonstrated by nitrogen seeding. The differences in confinement and pedestal behaviour before and after the ITER-like wall installation have been better characterized towards the development of high fusion yield scenarios in DT. Post-mortem analyses of the plasma-facing components have confirmed the previously reported low fuel retention obtained by gas balance and shown that the pattern of deposition within the divertor has changed significantly with respect to the JET carbon wall campaigns due to the absence of thermally activated chemical erosion of beryllium in contrast to carbon. Transport to remote areas is almost absent and two orders of magnitude less material is found in the divertor.
Published: 2015
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327. Dual sightline measurements of MeV range deuterons with neutron and gamma-ray spectroscopy at JET

Author: Eriksson, Jacob, Nocente, Massimo, Binda, Federico, Cazzaniga, Carlo, Conroy, Sean, Ericsson, Göran, Gorini, Giuseppe, Hellesen, Carl, Hjalmarsson, Anders, Sharapov, Sergei, Skiba, Mateusz, Tardocchi, Marco, Weiszflog, Matthias, Eriksson, Jacob, Nocente, Massimo, Binda, Federico, Cazzaniga, Carlo, Conroy, Sean, Ericsson, Göran, Gorini, Giuseppe, Hellesen, Carl, Hjalmarsson, Anders, Sharapov, Sergei, Skiba, Mateusz, Tardocchi, Marco, and Weiszflog, Matthias
Abstract: Observations made in a JET experiment aimed at accelerating deuterons to the MeV range by third harmonic radio-frequency (RF) heating coupled into a deuterium beam are reported. Measurements are based on a set of advanced neutron and gamma-ray spectrometers that, for the first time, observe the plasma simultaneously along vertical and oblique lines of sight. Parameters of the fast ion energy distribution, such as the high energy cut-off of the deuteron distribution function and the RF coupling constant, are determined from data within a uniform analysis framework for neutron and gamma-ray spectroscopy based on a one-dimensional model and by a consistency check among the individual measurement techniques. A systematic difference is seen between the two lines of sight and is interpreted to originate from the sensitivity of the oblique detectors to the pitch-angle structure of the distribution around the resonance, which is not correctly portrayed within the adopted one dimensional model. A framework to calculate neutron and gamma-ray emission from a spatially resolved, two-dimensional deuteron distribution specified by energy/pitch is thus developed and used for a first comparison with predictions from ab initio models of RF heating at multiple harmonics. The results presented in this paper are of relevance for the development of advanced diagnostic techniques for MeV range ions in high performance fusion plasmas, with applications to the experimental validation of RF heating codes and, more generally, to studies of the energy distribution of ions in the MeV range in high performance deuterium and deuterium-tritium plasmas.
Published: 2015
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328. Fuel ion ratio determination in NBI heated deuterium tritium fusion plasmas at JET using neutron emission spectrometry

Author: Hellesen, Carl, Eriksson, Jacob, Binda, Federico, Conroy, Sean, Ericsson, Göran, Hjalmarsson, Anders, Skiba, Mateusz, Weiszflog, Matthias, Hellesen, Carl, Eriksson, Jacob, Binda, Federico, Conroy, Sean, Ericsson, Göran, Hjalmarsson, Anders, Skiba, Mateusz, and Weiszflog, Matthias
Abstract: The fuel ion ratio ( n t / n d ) is of central importance for the performance and control of a future burning fusion plasma, and reliable measurements of this quantity are essential for ITER. This paper demonstrates a method to derive the core fuel ion ratio by comparing the thermonuclear and beam-thermal neutron emission intensities, using a neutron spectrometer. The method is applied to NBI heated deuterium tritium (DT) plasmas at JET, using data from the magnetic proton recoil spectrometer. The trend in the results is consistent with Penning trap measurements of the fuel ion ratio at the edge of the plasma, but there is a discrepancy in the absolute values, possibly owing to the fact that the two measurements are weighted towards different parts of the plasma. It is suggested to further validate this method by comparing it to the traditionally proposed method to estimate n t / n d from the ratio of the thermal DD and DT neutron emission components. The spectrometer requirements for measuring n t / n d at ITER are also briefly discussed.
Published: 2015
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329. Dual sightline measurements of MeV range deuterons with neutron and gamma-ray spectroscopy at JET

Author: Barcelona Supercomputing Center, Eriksson, Johan, Scopus - Author details - Nocente, Massimo, Binda, Federico, Scopus - Author details - Cazzaniga, Carlo, Conroy, Sean W., Ericsson, Göran N., Giacomelli, Luca C., Gorini, Giuseppe, Hellesen, Carl, Hellsten, Törbjrn, Hjalmarsson, Anders, Jacobsen, Arnhild S., Johnson, Thomas, Kiptily, Vasily, Koskela, Tuomas, Mantsinen, Mervi, Salewski, Mirko, Schneider, Michael, Sharapov, Sergei, Skiba, Mateusz, Tardocchi, Marco, Weiszflog, Matthias, Barcelona Supercomputing Center, Eriksson, Johan, Scopus - Author details - Nocente, Massimo, Binda, Federico, Scopus - Author details - Cazzaniga, Carlo, Conroy, Sean W., Ericsson, Göran N., Giacomelli, Luca C., Gorini, Giuseppe, Hellesen, Carl, Hellsten, Törbjrn, Hjalmarsson, Anders, Jacobsen, Arnhild S., Johnson, Thomas, Kiptily, Vasily, Koskela, Tuomas, Mantsinen, Mervi, Salewski, Mirko, Schneider, Michael, Sharapov, Sergei, Skiba, Mateusz, Tardocchi, Marco, and Weiszflog, Matthias
Abstract: Observations made in a JET experiment aimed at accelerating deuterons to the MeV range by third harmonic radio-frequency (RF) heating coupled into a deuterium beam are reported. Measurements are based on a set of advanced neutron and gamma-ray spectrometers that, for the first time, observe the plasma simultaneously along vertical and oblique lines of sight. Parameters of the fast ion energy distribution, such as the high energy cut-off of the deuteron distribution function and the RF coupling constant, are determined from data within a uniform analysis framework for neutron and gamma-ray spectroscopy based on a one-dimensional model and by a consistency check among the individual measurement techniques. A systematic difference is seen between the two lines of sight and is interpreted to originate from the sensitivity of the oblique detectors to the pitch-angle structure of the distribution around the resonance, which is not correctly portrayed within the adopted one dimensional model. A framework to calculate neutron and gamma-ray emission from a spatially resolved, two-dimensional deuteron distribution specified by energy/pitch is thus developed and used for a first comparison with predictions from ab initio models of RF heating at multiple harmonics. The results presented in this paper are of relevance for the development of advanced diagnostic techniques for MeV range ions in high performance fusion plasmas, with applications to the experimental validation of RF heating codes and, more generally, to studies of the energy distribution of ions in the MeV range in high performance deuterium and deuterium-tritium plasmas., This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission., Postprint (author's final draft)
Published: 2015

330. Monte Carlo Simulation Of The Data Acquisition Chain Of Scintillation Detectors

Author: Binda, Federico, Ericsson, Göran, Hellesen, Carl, Hjalmarsson, Anders, Eriksson, Jacob, Skiba, Mateusz, Conroy, Sean, Weiszflog, Matthias, Binda, Federico, Ericsson, Göran, Hellesen, Carl, Hjalmarsson, Anders, Eriksson, Jacob, Skiba, Mateusz, Conroy, Sean, and Weiszflog, Matthias
Abstract: The good performance of a detector can be strongly affected by the instrumentation used to acquire the data. The possibility of anticipating how the acquisition chain will affect the signal can help in finding the best solution among different set-ups. In this work we developed a Monte Carlo code that aims to simulate the effect of the various components of a digital Data Acquisition system (DAQ) applied to scintillation detectors. The components included in the model are: the scintillator, the photomultiplier tube (PMT), the signal cable and the digitizer. We benchmarked the code against real data acquired with a NE213 scintillator, comparing simulated and real signal pulses induced by gamma-ray interaction. Then we studied the dependence of the energy resolution of a pulse height spectrum (PHS) on the sampling frequency and the bit resolution of the digitizer. We found that exceeding some values of the sampling frequency and the bit resolution improves only marginally the performance of the system. The method can be applied for the study of various detector systems relevant for nuclear techniques, such as in fusion diagnostics.
Published: 2014
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331. Neutron spectrometry measurements of energetic deuterons in ICRF heated plasmas with the ITER-like wall at JET

Author: Eriksson, Jacob, Binda, Federico, Conroy, Sean, Ericsson, Göran, Hellesen, Carl, Hjalmarsson, Anders, Lerche, E., Skiba, Mateusz, Van Eester, D., Weiszflog, Matthias, Eriksson, Jacob, Binda, Federico, Conroy, Sean, Ericsson, Göran, Hellesen, Carl, Hjalmarsson, Anders, Lerche, E., Skiba, Mateusz, Van Eester, D., and Weiszflog, Matthias
Abstract: At JET, experiments have been conducted in order to optimize the performance of ion cyclotron radio-frequency (ICRF) heating in the presence of the newly installed ITER-like wall. The ICRF was tuned to the cyclotron frequency of minority hydrogen (H), which is also the 2nd harmonic of the cyclotron frequency of deuterium (D). The relative H concentration was varied from a few percent up to about 25 percent in a series of plasma discharges and the neutron time-of-flight spectrometer TOFOR was used to measure the energy spectrum of neutrons from the D(D,n)3He reaction during these discharges. It could be seen that the signal from ICRF accelerated deuterons depended strongly on H concentration. This observation indicates that the ICRF power absorbed by D at the 2nd harmonic cyclotron resonance increases with decreasing H concentration. This is in qualitative agreement with theoretical expectations obtained from the plasma wave equation solver TOMCAT.
Published: 2014

332. Prospects for measuring the fuel ion ratio in burning ITER plasmas using a DT neutron emission spectrometer

Author: Hellesen, Carl, Skiba, Mateusz, Dzysiuk, N., Weiszflog, Matthias, Hjalmarsson, Anders, Ericsson, Göran, Conroy, Sean, Sundén, Erik Andersson, Eriksson, Jacob, Binda, Federico, Hellesen, Carl, Skiba, Mateusz, Dzysiuk, N., Weiszflog, Matthias, Hjalmarsson, Anders, Ericsson, Göran, Conroy, Sean, Sundén, Erik Andersson, Eriksson, Jacob, and Binda, Federico
Abstract: The fuel ion ratio n(t)/n(d) is an essential parameter for plasma control in fusion reactor relevant applications, since maximum fusion power is attained when equal amounts of tritium (T) and deuterium (D) are present in the plasma, i.e., n(t)/n(d) = 1.0. For neutral beam heated plasmas, this parameter can be measured using a single neutron spectrometer, as has been shown for tritium concentrations up to 90%, using data obtained with the MPR (Magnetic Proton Recoil) spectrometer during a DT experimental campaign at the Joint European Torus in 1997. In this paper, we evaluate the demands that a DT spectrometer has to fulfill to be able to determine n(t)/n(d) with a relative error below 20%, as is required for such measurements at ITER. The assessment shows that a back-scattering time-of-flight design is a promising concept for spectroscopy of 14 MeV DT emission neutrons.
Published: 2014
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333. Assessment of Upgrades of the TOFOR Time-of-Flight Neutron Spectrometer in View of Future DT Operations at JET and For ITER : JW13-FT-4.34

Author: Skiba, Mateusz and Skiba, Mateusz
Published: 2014

334. Design of a Backscatter 14-MeV Neutron Time-of-Flight Spectrometer for Experiments at ITER

Author: Dzysiuk, Nataliia, Hellesen, Carl, Conroy, Sean, Ericsson, Göran, Hjalmarsson, Anders, Skiba, Mateusz, Dzysiuk, Nataliia, Hellesen, Carl, Conroy, Sean, Ericsson, Göran, Hjalmarsson, Anders, and Skiba, Mateusz
Abstract: Neutron energy spectrometry diagnostics play an important role in present-day experiments related to fusion energy research. Measurements and thorough analysis of the neutron emission from the fusion plasma give information on a number of basic fusion performance quantities, on the condition of the neutron source and plasma behavior. Here we discuss the backscatter Time-of-Flight (bTOF) spectrometer concept as a possible instrument for performing high resolution measurements of 14 MeV neutrons. The instrument is based on two sets of scintillators, a first scatterer exposed to a collimated neutron beam and a second detector set placed in the backward direction. The scintillators of the first set are enriched in deuterium to achieve neutron backscattering. The energy resolution and efficiency of a bTOF instrument have been determined for various geometrical configurations. A preliminary design of optimal geometry for the two scintillator sets has been obtained by Monte Carlo simulations based on the MCNPX code.
Published: 2014
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335. Impact of digitization for timing and pulse shape analysis of scintillator detector signals

Author: Hellesen, Carl, Skiba, Mateusz, Ericsson, Göran, Sundén, E. Andersson, Binda, Federico, Conroy, Sean, Eriksson, Jakob, Weiszflog, Matthias, Hellesen, Carl, Skiba, Mateusz, Ericsson, Göran, Sundén, E. Andersson, Binda, Federico, Conroy, Sean, Eriksson, Jakob, and Weiszflog, Matthias
Abstract: In this paper we investigate the effects of full digitization of scintillator signals. The requirements on the analog to digital converter (ADC), in terms of sampling rate (f(s)) and bit resolution, are investigated. Two applications for scintillator detectors are studied, pulse timing and particle species identification. We find that signal reconstruction using sinc interpolation can be used e.g. for high-precision timing of a sampled electric pulse. Timing performances better than 6 ps (FWHM) were obtained if f(s) equals or exceeds twice the maximum frequency of the scintillator pulse. Failing to meet this criterion deteriorates both the performance of pulse timing and particle identification. We find that the bit resolution of the ADC is very important also for timing of pulses.
Published: 2013
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336. Fully digital data acquisition system for the neutron time-of-flight spectrometer TOFOR at JET

Author: Skiba, Mateusz, Weiszflog, Matthias, Hjalmarsson, Anders, Ericsson, Göran, Hellesen, Carl, Conroy, Sean, Andersson-Sundén, E., Eriksson, Jacob, Binda, Federico, Skiba, Mateusz, Weiszflog, Matthias, Hjalmarsson, Anders, Ericsson, Göran, Hellesen, Carl, Conroy, Sean, Andersson-Sundén, E., Eriksson, Jacob, and Binda, Federico
Abstract: A prototype of a fully digital data acquisition system based on 1 Gsps 12 bit digitizers for the TOFOR fusion neutron spectrometer at JET is assessed. The prototype system enables the use of geometry-based background discrimination techniques, which are modeled, evaluated, and compared to experimental data. The experimental results are in line with the models and show a significant improvement in signal-to-background ratio in measured time-of-flight spectrum compared to the existing data acquisition system.
Published: 2012
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337. Fuel ion ratio measurements in reactor relevant neutral beam heated fusion plasmas

Author: Hellesen, Carl, Eriksson, Jacob, Conroy, Sean, Ericsson, Göran, Skiba, Mateusz, Weiszflog, Matthias, Hellesen, Carl, Eriksson, Jacob, Conroy, Sean, Ericsson, Göran, Skiba, Mateusz, and Weiszflog, Matthias
Abstract: In this paper, we present a method to derive n tn d using the ratio of the thermonuclear neutron emission to the beam-target neutron emission. We apply it to neutron spectroscopy data from the magnetic proton recoil spectrometer taken during the deuterium tritium experiment at JET. n tn d-values obtained using neutron spectroscopy are in qualitative agreement with those from other diagnostics measuring the isotopic composition of the exhaust in the divertor.
Published: 2012
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338. Developments of time-of-flight and proton recoil neutron spectrometry techniques in view of a possible JET DT campaign and for ITER

Author: Andersson Sunden, E., Conroy, Sean, Ericsson, Göran, Hellesen, Carl, Skiba, Mateusz, Cecconello, Marco, Eriksson, Jacob, Sangaroon, Siriyaporn, Weiszflog, Matthias, Wodniak, Iwona, Andersson Sunden, E., Conroy, Sean, Ericsson, Göran, Hellesen, Carl, Skiba, Mateusz, Cecconello, Marco, Eriksson, Jacob, Sangaroon, Siriyaporn, Weiszflog, Matthias, and Wodniak, Iwona
Abstract: Source: Scopus
Published: 2011

339. Finite Larmor radii effects in fast ion measurements as demonstrated using neutron emission spectrometry of JET plasmas heated with 3rd harmonic ICRF

Author: Eriksson, Jacob, Hellesen, Carl, Andersson Sundén, Erik, Cecconello, Marco, Conroy, Sean, Ericsson, Göran, Gatu Johnson, Maria, Pinches, S.D., Sangaroon, Siriyaporn, Sharapov, S.E., Skiba, Mateusz, Weiszflog, Matthias, Klimek, Iwona, Eriksson, Jacob, Hellesen, Carl, Andersson Sundén, Erik, Cecconello, Marco, Conroy, Sean, Ericsson, Göran, Gatu Johnson, Maria, Pinches, S.D., Sangaroon, Siriyaporn, Sharapov, S.E., Skiba, Mateusz, Weiszflog, Matthias, and Klimek, Iwona
Abstract: This paper demonstrates how the finite Larmor radii (FLR) of fast ions can affect fast ion measurements by studying data from the neutron time-of-flight spectrometer TOFOR. Neutron spectra were calculated from a model of the fast ion velocity distribution for a JET experiment with 3rd harmonic ICRF heating of deuterium beams. It was found that FLR effects need to be considered to get a good description of the data, if the Larmor radius of the fast ions are comparable to the width of the field of view of the instrument. This applies not only to results from neutron spectrometry but also to other types of fast ion diagnostics.
Published: 2011

340. Analysis of fusion neutron time-of-flight spectra using kinematic background discrimination

Author: Skiba, Mateusz, Eriksson, Jacob, Conroy, Sean, Hellesen, Carl, Hjalmarsson, Anders, Andersson-Sundén, E., Skiba, Mateusz, Eriksson, Jacob, Conroy, Sean, Hellesen, Carl, Hjalmarsson, Anders, and Andersson-Sundén, E.

341. Comparison of minichromosome maintenance proteins (MCM-3, MCM-7) and metallothioneins (MT-I/II, MT-III) expression in relation to clinicopathological data in ovarian cancer.

Author: Kobierzycki C, Pula B, Skiba M, Jablonska K, Latkowski K, Zabel M, Nowak-Markwitz E, Spaczynski M, Kedzia W, Podhorska-Okolow M, and Dziegiel P
Subjects: Adult, Aged, Biomarkers, Tumor metabolism, Female, Humans, Middle Aged, Ovarian Neoplasms pathology, Metallothionein metabolism, Minichromosome Maintenance Proteins metabolism, Ovarian Neoplasms metabolism
Abstract: Background: Despite great progress in the understanding of ovarian cancer biology, clinicopathological data (i.e. grade, stage, histological type and residual disease after surgery) seem to be the most important prognostic factors., Materials and Methods: The present study aimed to investigate the relationship between expression of minichromosome maintenance proteins (MCM-3, MCM-7), metallothioneins (MT-I/II, MT-III), and Ki-67 in 103 ovarian cancer cases, mostly of the serous histological type., Results: Statistical analysis revealed strong positive correlations in the expression of MCM-3 vs. Ki-67 (r=0.492), MCM-7 vs. Ki-67 (r=0.651), and MCM-3 vs. MCM-7 (r=0.515) (all p<0.0001). The Kruskal-Wallis test showed an association of increased expression of MCM-3 and Ki-67 with increasing grade of histological malignancy (p=0.0011, p=0.029, respectively). Regarding clinical progression, cytoplasmic MT-I/II expression was significantly higher in more advanced disease stages (III+IV vs. I+II; p=0.0247)., Conclusion: Due to the correlations shown here, the determination of MCM proteins as proliferation markers of ovarian cancer, should be strongly considered.
Published: 2013

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