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Kinetic instabilities in a dense plasma of a continuous ECR discharge in a mirror magnetic trap at the GISMO setup are studied. We experimentally define unstable regimes and corresponding plasma parameters, where the excitation of electromagnetic emission is observed, accompanied by the precipitation of energetic electrons from the magnetic trap. Comprehensive experimental study of the precipitating electron energy distribution and plasma electromagnetic emission spectra, together with theoretical estimates of the cyclotron instability increment proves that under the experimental conditions the observed instability is related to the excitation of whistler-mode waves, which are a driver of losses of energetic electrons from the magnetic trap. The results of this study are important for the further development of the GISMO ECRIS facility and for the improvement of its parameters as an ion source. Also, this research of plasma kinetic instabilities is of fundamental interest and provides experimental tools to simultaneously study plasma electromagnetic activity and corresponding changes in a resonant electron energy distribution., Comment: 9 pages, 9 figures, submitted to Physics of Plasmas

To ensure further progress in the development of electron cyclotron resonance ion sources (ECRISs), deeper understanding of the underlying physics is required. The electron energy distribution (EED), which is crucial for the performance of an ECRIS, still remains obscure. The present paper focuses on the details of a well-developed technique of measuring the EED of electrons escaping axially from the magnetically confined plasma of an ECRIS. The method allows for better than 500 eV energy resolution over a range of electron energies from 4 keV to over 1 MeV. We present detailed explanation of the experimental procedure and the following data processing peculiarities with examples and discuss possible reasons of energetic electron losses from the magnetic trap, in particular the role of RF pitch angle scattering. Finally, an experimental method of approximating the confined EED based on the measurement of escaping electrons is described.

One of the major trends in the development of ECR sources of multicharged ions is an increase of the extracted ion current. The main factor affecting the current of an ion beam produced by such a source is, obviously, the density of the plasma from which ions are extracted. In the present article the mean ion charge, the ion current density, and the minimal microwave power required to sustain needed electron temperature are calculated for a broad range of plasma densities (up to 1014 cm−3, which corresponds to 90 GHz cutoff frequency of microwave pumping). The electron temperature is taken as granted and no effects due to instabilities are considered. The distinguishing future of the analysis performed is that it takes into account alteration of the regime of plasma confinement, which occurs as the plasma density is increased. If the plasma density exceeds a certain threshold, the classical Pastukhov’s regime of plasma confinement is replaced by the quasi-gas-dynamic regime. It is demonstrated, in particu...

Modern way of ECR multicharged ion sources development is connected with increasing of microwave frequency up to tens of GHz. Millimeter wave gyrotrons are used now in several laboratories. Traditional mirror magnetic traps with min B configuration for suppressing of MHD instabilities became too expensive because very strong magnetic fields are required. So prospection of axisymmetric plasma trap with MHD stabilization is quite relevant subject of modern plasma physics. The simplest trap of such kind is cusp one. The zero level of magnetic field in the center of the trap doesn’t allow to achieve a good confinement in classical regime. A gasdynamic regime of plasma confinement was studied in [1]. The same regime may be realized in the cusp geometry trap if plasma density is high enough.In present work a theoretical model of quasi‐gasdynamic plasma confinement in a cusp trap is developed. The possibilities of multicharged ion generation in a plasma confined in a cusp trap under the conditions of powerful EC...

Neutrino oscillations have implications for the Standard Model of particle physics. The CERN Beta Beam has outstanding capabilities to contribute to precision measurements of the parameters governing neutrino oscillations. The FP7 collaboration EUROnu (2008-2012) is a design study that will review three facilities (Super-Beams, Beta Beams and Neutrino Factories) and perform a cost assessment that, coupled with the physics performance, will give means to the European research authorities to make decisions on future European neutrino oscillation facilities. "Beta Beams" produce collimated pure electron (anti)neutrinos by accelerating beta active ions to high energies and having them decay in a storage ring. Using existing machines and infrastructure is an advantage for the cost evaluation; however, this choice is also constraining the Beta Beams. Recent work to make the Beta Beam facility a solid option will be described: production of Beta Beam isotopes, the 60 GHz pulsed ECR source development, integration into the LHC-upgrades, insure the high intensity ion beam stability, and optimizations to get high neutrino fluxes. The costing approach will also be described. Copyright ?????? 2012 by IEEE.

The discovery that the neutrino changes flavor as it travels through space has implications for the Standard Model of particle physics (SM)[1]. To know the contribution of neutrinos to the SM, needs precise measurements of the parameters governing the neutrino oscillations. This will require a high intensity beam-based neutrino oscillation facility. The EURO?????? Design Study will review three currently accepted methods of realizing this facility (the so-called Super-Beams, Beta Beams and Neutrino Factories) and perform a cost assessment that, coupled with the physics performance, will give means to the European research authorities to make a decision on the lay-out and construction of the future European neutrino oscillation facility. "Beta Beams" produce collimated pure electron neutrino and antineutrino beams by accelerating beta active ions to high energies and letting them decay in a race-track shaped storage ring. EURO?????? Beta Beams are based on CERNs infrastructure and the fact that some of the already existing accelerators can be used. To use existing machines is a strong advantage for the cost evaluation, however this choice is also constraining the Beta Beams. In this article we describe recent work that has made the Beta Beam facility a solid option for neutrino production: new ideas and developments to produce and collect different Beta Beam isotopes, the 60 GHz pulsed ECR source development, the integration of Beta Beams in the upgrade program for LHC, work to ensure the very high intensity ion beam stability in the different machines, and optimizations of the decay ring to get high neutrino flux at a gamma boost of 100. Copyright ?????? 2011 by IPAC'11/EPS-AG.