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A new thermography system with high time resolution was put into operation at ASDEX-Upgrade and is routinely used to determine the energy flux onto the lower diverter plates. The measurements allow the power deposition to be chamcterized during dynamic events such as ELMS and disruptions, as well as the asymmetry of the inboardloutboard power load. A power balance is set up even during single discharges and the losses are found to be fairly equal to the power input.

Adiabatic vacuum states are a well-known class of physical states for linear quantum fields on Robertson-Walker spacetimes. We extend the definition of adiabatic vacua to general spacetime manifolds by using the notion of the Sobolev wavefront set. This definition is also applicable to interacting field theories. Hadamard states form a special subclass of the adiabatic vacua. We analyze physical properties of adiabatic vacuum representations of the Klein-Gordon field on globally hyperbolic spacetime manifolds (factoriality, quasiequivalence, local definiteness, Haag duality) and construct them explicitly, if the manifold has a compact Cauchy surface. W. Junker and E. SchroheAnn. Henri Poincaré can be extended to interacting fields, in close analogy to the Hadamard states. It turned out that the notion of the Sobolev (or H s -) wavefront set is the appropriate mathematical tool for this purpose. In Appendix B we review this notion and the calculus related to it.After an introduction to the structure of the algebra of observables of the Klein-Gordon quantum field on a globally hyperbolic spacetime manifold (M, g) in Section 2 we present our definition of adiabatic states of order N (Definition 3.2) in Section 3. It contains the Hadamard states as a special case: They are adiabatic states "of infinite order". To decide which order of adiabatic vacuum is physically admissible we investigate the algebraic structure of the corresponding GNS-representations. Haag, Narnhofer & Stein [23] suggested as a criterion for physical representations that they should locally generate von Neumann factors that have all the same set of normal states (in other words, the representations are locally primary and quasiequivalent). We show in Section 4.1 (Theorem 4.5 and Theorem 4.7) that this is generally the case if N > 5/2. For the case of pure states on a spacetime with compact Cauchy surface, which often occurs in applications, we improve the admissible order to N > 3/2. In addition, in Section 4.2 we show that adiabatic vacua of order N > 5/2 satisfy the properties of local definiteness (Corollary 4.13) and those of order N > 3/2 Haag duality (Theorem 4.15). These results extend corresponding statements for adiabatic vacuum states on Robertson-Walker spacetimes due to Lüders & Roberts [35], and for Hadamard states due to Verch [49]; for their discussion in the framework of algebraic quantum field theory we refer to [21]. In Section 5 we explicitly construct pure adiabatic vacuum states on an arbitrary spacetime manifold with compact Cauchy surface (Theorem 5.10). In Section 6 we show that our adiabatic states are indeed a generalization of the well-known adiabatic vacua on Robertson-Walker spaces: Theorem 6.3 states that the adiabatic vacua of order n (according to the definition of [35]) on a Robertson-Walker spacetime with compact spatial section are adiabatic vacua of order 2n in the sense of our microlocal Definition 3.2. We conclude in Section 7 by summarizing the physical interpretation of our mathematical analysis and calcula...

Quasifree states of a linear Klein-Gordon quantum field on globally hyperbolic spacetime manifolds are considered. After a short mathematical review techniques from the theory of pseudodifferential operators and wavefront sets on manifolds are used to develop a criterion for a state to be an Hadamard state. It is proven that ground- and KMS-states on certain static spacetimes and adiabatic vacuum states on Robertson-Walker spaces are Hadamard states. A counterexample is given which shows that the idea of instantaneous positive energy states w.r.t. a Cauchy surface does in general not yield physical states. Finally, the problem of constructing Hadamard states on arbitrary curved spacetimes is solved in principle.

In the ASDEX Upgrade, X-point marfe formation and its behaviour up to the density limit is investigated in gas-fuelled ohmically-heated single-null discharges over a wide range of pameters: Ip = 0.6-1.2 MA, Bw = I .35-2.4 T, a plasma elongation of 1.6 and 2 , ~ c 2. The standard-ion VB drifl is directed towards the X-point. At medium electron densities inevitably a marfe develops in the vicinity of the active X-point The marfe formation is consistent with a model of thermal instabilities in the radiating edge plasma. Moreover, stable steady-state operation is demonstrated with marfes which can extend significmtly into the bulk plasma. The density limit is always connected with quick m d e expansion and movement followed by mode-locking leading to a major disruption. The limit scales linwly with In md is in good agreement with the Greenwald density limit scaling. The resulting experimental Hugill limit is E,Rqv5 / B E = 2.8 x IO2" m-2 T I . Reversal of the ion VB drift direction away from the target has a detrimental effect an the density limit.