We propose to produce neutron-rich nuclei in the range of the astrophysical r-process (the rapid neutron-capture process) around the waiting point N = 126 [1,2,3] by fissioning a dense laser-accelerated thorium ion bunch in a thorium target (covered by a polyethylene layer, CH 2 ), where the light fission fragments of the beam fuse with the light fission fragments of the target. Via the 'hole-boring' (HB) mode of laser Radiation Pressure Acceleration (RPA) [4,5,6] using a high-intensity, short pulse laser, very efficiently bunches of 232 Th with solid-state density can be generated from a Th layer (ca. 560 nm thick), placed beneath a deuterated polyethylene foil (CD 2 with ca. 520 nm), both forming the production target. Th ions laser-accelerated to about 7 MeV/u will pass through a thin CH 2 layer placed in front of a thicker second Th foil (both forming the reaction target) closely behind the production target and disintegrate into light and heavy fission fragments. In addition, light ions (d,C) from the CD 2 production target will be accelerated as well to about 7 MeV/u, inducing the fission process of 232 Th also in the second Th layer. The laser-accelerated ion bunches with solid-state density, which are about 10 14 times more dense than classically accelerated ion bunches, allow for a high probability that generated fission products can fuse again when the fragments from the thorium beam strike the Th layer of the reaction target. In contrast to classical radioactive beam facilities, where intense but low-density radioactive beams of one ion species are merged with stable targets, the novel fissionfusion process draws on the fusion between neutron-rich, short-lived, light fission fragments both from beam and target. Moreover, the high ion beam density may lead to a strong collective modification of the stopping power in the target by 'snowplough-like' removal of target electrons, leading to significant range enhancement, thus allowing to use rather thick targets. Send offprint requests to:Using a high-intensity laser with two beams with a total energy of 300 J, 32 fs pulse length and 3 µm focal diameter, as, e.g., envisaged for the ELI-Nuclear Physics project in Bucharest (ELI-NP) [7], order-of-magnitude estimates promise a fusion yield of about 10 3 ions per laser pulse in the mass range of A = 180 − 190, thus enabling to approach the r-process waiting point at N=126. First studies on ion acceleration, collective modifications of the stopping behaviour and the production of neutronrich nuclei can also be performed at the upcoming new laser facility CALA (Center for Advanced Laser Applications) in Garching.

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Several techniques exist to obtain brilliant X-ray beams by coherent reflection from relativistic electrons (E e = γ mc 2 ) with Doppler frequency upshift of 4γ 2 . We describe a new approach starting with an ultra-thin solid target. Larger 'driver'-laser intensities with high contrast are required to produce dense electron sheets. Their acceleration in vacuum results in a transverse momentum component besides the dominant longitudinal momentum component. The counter-propagating 'production' laser for optimum Doppler boost in X-ray production by reflection has to be injected opposite to the electron direction and not opposite to the driver laser. Different measures to increase the reflectivity of the electron sheet via laser trapping or freeelectron-laser-like micro-bunching are discussed, extending the photon energy into the MeV range. Here, first-order estimates are given.

market is defined to be efficient if there exists no profitable trading strategy. This has to hold even if all currently available information about the market (excluding inside information) has been skillfully used. The question of whether or not a market satisfies this criterion is of considerable interest as participants can engage in efficient markets at less transaction costs as in markets which necessitate extensive information search.For a commodity which is traded on spot and on futures markets, the prices on the two respective markets become central to the question of market efficiency. In a futures market hedgers can secure a certain price for a commodity at a future delivery date. The futures price also conveys information about the cash price at the maturity of the futures contract in that it reflects the different cash price expectations of the market participants at the time of contracting. Such information will be particularly important for agents not fully hedged as well as for market participants planning for future production or use. This article will concentrate on information aspects of futures prices and will disregard the security trade aspect.In the futures market, prices are created via the balancing of supply and demand which themselves are contingent upon the information currently underlying the market process. This knowledge consists partly of past prices from the same market, so that the new prices become part of subsequent information sets. In this sense, trading on futures markets (as on markets in *This article reports research undertaken in a project on the effects of international raw material market regulation on growth and allocation in developing countries funded by the "Deutsche Forschungsgemeinschaft." The author wishes to thank Egbert Gerken and Rolf J. Langhammer for many helpful suggestions.

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