1 See appendix. 2 See the author list of 'Overview of progress in European Medium Sized Tokamaks towards an integrated plasma-edge/wall solution' by Meyer [22].

Feedback-controlled puffing of neon and deuterium has been applied to control the edge-localizedmode behavior and the target plate power deposition during high-power H-mode discharges in ASDEX Upgrade.A regime has been found in which more than 90% of the heating power is lost through radiation and divertor detachment occurs, without deterioration of the energy confinement. The plasma remains in the 0 mode, exhibiting small-amplitude, high-frequency ELM's, which do not penetrate to the target plates in the strike zone region. PACS numbers: 52.55.Fa Reduction of the energy Aux density to the target plates to below the values attainable by purely geometric spreading of the divertor fan is one of the most critical requirements for a fusion reactor [1]. Impurity radiation losses from the outer regions of the main plasma and scrape-off layer are, at present, considered the most viable option for attaining such a mode of operation [2]. The resulting state corresponds to a low-power Bow to the target plates (~0.1 of the total heating power), and low plasma densities and pressures in front of them, and has been termed detachment [3]. Experimentally, this aim has been pursued by raising the edge plasma density by strong gas puffing, and by the controlled introduction of light impurities. The most successful previous experiments, with strong additional heating, had involved feedback control of either the impurity puff (in TEXTOR [4]) or of the deuterium puff rate (in JET [5]). While continuous detachmentcould thereby be achieved in limiter and L-mode divertor discharges, experiments in H-mode resulted in either a relapse into the L regime or a reduction only of the time-averaged power Row, with heat pulses associated with edge localized modes (ELM's) still penetrating to the target plates [6,7].The experiments on the ASDEX Upgrade reported here, were employed for the first time in a divertor tokamak feedback control of the radiated power losses through impurity (neon) addition. Simultaneously, we applied deuterium gas puffing, feedback controlling, and also the divertor neutral density. In the most successful operating mode, we attained divertor detachment both in between and during ELM s, while maintaining standard H-regime energy confinement.Device, operating range, and diagnostics description -ASDEX Up.grade is a midsize tokamak (Ro = 1.65 m, a = 0.5 m, and plasma elongation b/a = 1.6) with a single null divertor (Fig. 1). All plasma-facing components are graphite-covered, the vessel is routinely boronized, and turbomolecular pumps allow control of the hydrogen and noble gas particle content of the vessel. The experiments described here were carried out in deuterium, with n,~1.2 X 10 m

Following the first observation of an astrophysical high-energy neutrino flux with the IceCube Neutrino Observatory in 2013 and the identification of a first cosmic high-energy neutrino source in 2017, the detector will be upgraded with about 700 new advanced optical sensors. This will expand IceCube's capabilities both at low and high neutrino energies. A large fraction of the upgrade modules will be multi-PMT Digital Optical Modules, mDOMs, each featuring 24 three-inch class photomultiplier tubes (PMTs) pointing uniformly in all directions, thereby providing an almost homogeneous angular coverage. The signal from each PMT is digitized individually, providing directional information for the incident photons. Together, the 24 PMTs provide an effective photosensitive area more than twice than that of the current IceCube optical module. The main mDOM design challenges arise from the constraints on the module size and power needed for the 24-channel high-voltage and readout systems. This contribution presents an mDOM design that meets these challenges and discusses the sensitivities expected from these modules.

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