0000000000239119
AUTHOR
D. Molina
VizieR Online Data Catalog: 46 open clusters GaiaDR2 HR diagrams (Gaia Collaboration, 2018)
We have determined the membership of 46 open clusters. For the nine clusters within 250pc we determined optimised parallaxes based on the combined information extracted from the measured parallax and proper motion values. These clusters are : in Tables A1a & A3: alphaPer, Blanco1, ComaBer, Hyades, IC2391, IC2602, NGC2451A, Pleiades, Praesepe. The remaining 37 clusters are in Table A1b & A4: Coll140, IC4651, IC4665, IC4725, IC4756, NGC0188, NGC0752, NGC0869, NGC0884, NGC1039, NGC1901, NGC2158, NGC2168, NGC2232, NGC2323, NGC2360, NGC2422, NGC2423, NGC2437, NGC2447, NGC2516, NGC2547, NGC2548, NGC2682, NGC3228, NGC3532, NGC6025, NGC6281, NGC6405, NGC6475, NGC6633, NGC6774, NGC6793, NGC7092, Sto…
Efficient generation of energetic ions in multi-ion plasmas by radio-frequency heating
We describe a new technique for the efficient generation of high-energy ions with electromagnetic ion cyclotron waves in multi-ion plasmas. The discussed ‘three-ion’ scenarios are especially suited for strong wave absorption by a very low number of resonant ions. To observe this effect, the plasma composition has to be properly adjusted, as prescribed by theory. We demonstrate the potential of the method on the world-largest plasma magnetic confinement device, JET (Joint European Torus, Culham, UK), and the high-magnetic-field tokamak Alcator C-Mod (Cambridge, USA). The obtained results demonstrate efficient acceleration of 3He ions to high energies in dedicated hydrogen–deuterium mixtures.…
VizieR Online Data Catalog: Gaia DR2 sources in GC and dSph (Gaia Collaboration+, 2018)
The files contains lists of possible members of each of the objects (75 globular clusters, 9 dwarf spheroidal galaxies, the Bootes I UFD, the LMC and SMC). The stars in these lists have been selected and used to determine the astrometric parameters of the corresponding objects following either the procedures described in Sec. 2.1 (for the clusters and dwarfs) or in Sec. 2.2 (for the LMC and SMC). The first column is the "source_id" as given by Gaia, the ra and declination of the star in degrees, and its G-band magnitude (known as "photgmean_mag" in the Gaia archive). (2 data files).
Novel method for determination of tritium depth profiles in metallic samples
Tritium accumulation in fusion reactor materials is considered a serious radiological issue, therefore a lot of effort has been concentrated on the development of radiometric techniques. A novel method, based on gradual dissolution, for the determination of the total tritium content and its depth profiles in metallic samples is demonstrated. This method allows for the measurement of tritium in metallic samples after their exposure to a hydrogen and tritium mixture, tritium containing plasma or after irradiation with neutrons resulting in tritium formation. In this method, successive layers of metal are removed using an appropriate etching agent in the controlled regime and the amount of evo…
Intraoperative monitoring of cerebral blood flow during ventricular shunting in hydrocephalic pediatric patients.
Several studies have demonstrated lowered cerebral blood flow (CBF) in patients with hydrocephalus and symptoms of raised intracranial pressure. Ventricular shunting in such cases permits a sudden increase in CBF. The pathophysiology of functional brain deficit secondary to hydrocephalus is little understood. Improvement of the patient's clinical status after drainage of CSF suggests that cerebral dysfunction is not necessarily due to permanent brain damage. In fact, it improves rapidly after ventricular taps. In view of this it would be helpful to monitor cerebral perfusion. The transcranial Doppler (TCD) ultrasonography technique allows real-time monitoring of the intracranial circulation…
Comparison of the structure of the plasma-facing surface and tritium accumulation in beryllium tiles from JET ILW campaigns 2011-2012 and 2013-2014
In this study, beryllium tiles from Joint European Torus (JET) vacuum vessel wall were analysed and compared regarding their position in the vacuum vessel and differences in the exploitation conditions during two campaigns of ITER-Like-Wall (ILW) in 2011-2012 (ILW1) and 2013-2014 (ILW2) Tritium content in beryllium samples were assessed. Two methods were used to measure tritium content in the samples - dissolution under controlled conditions and tritium thermal desorption. Prior to desorption and dissolution experiments, scanning electron microscopy and energy dispersive x-ray spectroscopy were used to study structure and chemical composition of plasma-facing-surfaces of the beryllium sampl…
Overview of the JET results in support to ITER
The 2014–2016 JET results are reviewed in the light of their significance for optimising the ITER research plan for the active and non-active operation. More than 60 h of plasma operation with ITER first wall materials successfully took place since its installation in 2011. New multi-machine scaling of the type I-ELM divertor energy flux density to ITER is supported by first principle modelling. ITER relevant disruption experiments and first principle modelling are reported with a set of three disruption mitigation valves mimicking the ITER setup. Insights of the L–H power threshold in Deuterium and Hydrogen are given, stressing the importance of the magnetic configurations and the recent m…
Modelling of JET hybrid plasmas with emphasis on performance of combined ICRF and NBI heating
International audience; During the 2015--2016 JET campaigns, many efforts have been devoted to the exploration of high-performance plasma scenarios envisaged for DT operation in JET. In this paper, we review various key recent hybrid discharges and model the combined ICRF NBI heating. These deuterium discharges with deuterium beams had the ICRF antenna frequency tuned to match the cyclotron frequency of minority H at the centre of the tokamak coinciding with the second harmonic cyclotron resonance of D. The modelling takes into account the synergy between ICRF and NBI heating through the second harmonic cyclotron resonance of D beam ions, allowing us to assess its impact on the neutron rate…