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Low temperature plasmas (LTPs) enable to create a highly reactive environment at near ambient temperatures due to the energetic electrons with typical kinetic energies in the range of 1 to 10 eV (1 eV = 11600K), which are being used in applications ranging from plasma etching of electronic chips and additive manufacturing to plasma-assisted combustion. LTPs are at the core of many advanced technologies. Without LTPs, many of the conveniences of modern society would simply not exist. New applications of LTPs are continuously being proposed. Researchers are facing many grand challenges before these new applications can be translated to practice. In this paper, we will discuss the challenges being faced in the field of LTPs, in particular for atmospheric pressure plasmas, with a focus on health, energy and sustainability.

The management of ovarian endometriomas in women wishing to conceive remains challenging. Recent data suggest that excising endometriomas by ovarian tissue sparing cystectomy does not avoid inadvertent removal of ovarian parenchyma surrounding the cyst, particularly in enlarged cysts. Although several authors question whether the ovarian parenchyma immediately surrounding the cyst may still be functional, there is little doubt that postoperative fertility could be significantly impaired by loss of ovarian cortex and provokes the question as to whether pregnancy should be initiated before performing a cystectomy, whenever this scenario is possible. However ovarian surgery cannot always be delayed to the postpartum period, numerous women require endometrioma management while not seeking an immediate pregnancy and still wish to conserve their procreative capabilities. After a period of some years during which cystectomy appeared to be the best surgical technique in the treatment of ovarian endometriomas in women wishing to become pregnant, recent data have suggested that ablation of the inner layer of the endometrioma may be a valuable alternative technique, as long as the energy employed avoids thermal diffusion to surrounding ovarian tissue. The Department of Gynecology at the University Hospital in Rouen, France have introduced ablation by plasma energy using the PlasmaJet system (Plasma Surgical Ltd, Abingdon, UK) and have already been able to report encouraging results based on non comparative pilot studies and on retrospective "before and after" comparative study. The aim of the study is to prospectively compare loss of ovarian parenchyma and decrease in antral follicle count (AFC) following ovarian endometrioma ablation using plasma energy versus cystectomy, when performed by only two expert surgeons. Postoperative examination is carried out by 3D ultrasound. Objective: To compare loss of ovarian parenchyma following ovarian endometrioma ablation using the PlasmaJet system versus cystectomy, using postoperative examination by 3D ultrasound. Design: Prospective comparative study. Setting: Two experienced surgeons practicing in two University tertiary referral centers. Patients: Fifty women with no previous history of ovarian surgery managed for unilateral ovarian endometrioma > 30 mm in diameter. Interventions: Endometrioma ablation by plasma energy using the PlasmaJet system and ovarian tissue sparing cystectomy. Main Outcome Measures: 3D ultrasound assessment of postoperative reduction in ovarian volume and antral follicle count (AFC) .

Plasma simulations are often rendered challenging by the disparity of scales in time and in space which must be resolved. When these disparities are in distinctive zones of the simulation domain, a method which has proven to be effective in other areas (e.g., fluid dynamics simulations) is the mesh refinement technique. A brief discussion of the challenges posed by coupling this technique with plasma particle-in-cell simulations is given, followed by a presentation of examples of application in heavy ion fusion and related fields which illustrate the effectiveness of the approach. Finally, a report is given on the status of a collaboration under way at Lawrence Berkeley National Laboratory between the Applied Numerical Algorithms Group (ANAG) and the Heavy Ion Fusion group to upgrade ANAG’s mesh refinement library Chombo to include the tools needed by particle-in-cell simulation codes.

A mechanism is proposed and evaluated for driving rotation in tokamak plasmas by minority ion-cyclotron heating, even though this heating introduces negligible angular momentum. The mechanism has two elements: First, angular momentum transport is governed by a diffusion equation with a boundary condition at the separatrix. Second, Monte Carlo calculations show that ion-cyclotron energized particles will provide a torque density source which has a zero volume integral but separated positive and negative regions. With such a source, a solution of the diffusion equation predicts that ion-cyclotron heating will cause a rotational shear layer to develop. The corresponding jump in plasma rotation ΔΩ is found to be negative outwards when the ion-cyclotron surface lies on the low-field side of the magnetic axis and positive outwards with the resonance on the high-field side. The magnitude of the jump ΔΩ=(4qmaxWJ2*) (eBR3a2ne(2π)2)−1(τM/τE) where |J2*|≈2–4 is a nondimensional rotation frequency calculated by the Monte Carlo ORBIT code [R. B. White and M. S. Chance, Phys. Fluids 27, 2455 (1984)]. For a no-slip boundary condition when the resonance lies on the low-field side of the magnetic axis, the sense of predicted axial rotation is co-current and overall agreement with experiment is good. When the resonance lies on the high-field side, the predicted rotation becomes countercurrent for a no-slip boundary while the observed rotation remains co-current. The rotational shear layer position is controllable and of sufficient magnitude to affect microinstabilities.

A modulated electron beam is injected into a low .beta. plasma parallel to the confining field to investigate the energy-transfer-rate from the electron beam to the plasma. Parametric excitation of electrostatic lower-hybrid waves and ion cyclotron quasimodes is experimentally identified. The temperature of both ions and electrons is observed to increase significantly concomitant with the growth of the instability.

We present an extension of the B erenger Perfectly Matched Layer with additional terms and tunable coecien ts which introduce some asymmetry in the absorption rate. We show that the discretized version of the new PML oers superior absorption rates than the discretized standard PML under a plane wave analysis. Taking advantage of the high rates of absorption of the new PML, we have devised a new strategy for introducing the technique of Mesh Renemen t into electromagnetic Particle-In-Cell plasma simulations. We present the details of the algorithm as well as a 2-D example of its application to laser-plasma interaction in the context of fast ignition.

The MAPSYN project of the European Union (standing for Microwave, Acoustic and Plasma SYNtheses) aims at the utilization of plasma technology for nitrogen fixation reactions on an industrial scale and with industrial plasma reactor technology, developed and utilised commercially [1]. Key motif is enhanced energy efficiency to make an industrial plasma process viable for chemical industry. The corresponding enabling technologies – plasma catalysis, smart reactors (microreactors) and more – go beyond prior approaches. Continuing a first more project-based literature compilation, this overview focus on the two first enabling functions, plasma catalysis and smart reactor technology, which are reviewed for industrial and near-industrial plasma-based applications. It is thereby evident that notable promise is given for the nitrogen fixation as well and indeed this has been demonstrated also for nitrogen fixation; yet, initially and without the holistic system engineering dimension.

Self-consistent turbulent transport of high-concentration impurities in magnetically confined fusion plasmas is studied using a three-dimensional nonlinear fluid global turbulence model which includes ion-temperature gradient and trapped electron mode instabilities. It is shown that the impurity concentration can have a dramatic feedback in the turbulence and, as a result, it can significantly change the transport properties of the plasma. High concentration impurities can trigger strong intermittency that manifests in non-Gaussian heavy tails of the probability density functions of the E × B fluctuations and of the ion-temperature flux fluctuations. At the heart of this self-consistent coupling is the existence of inward propagating ion-temperature fronts with a sharp gradient at the leading edge that give rise to instabilities and avalanchelike bursty transport. Numerical evidence of time nonlocality (i.e., history dependence) in the delayed response of the flux to the gradient is presented.