Proton Emission Times in Spectator Fragmentation

Proton-proton correlations from spectator decays following Au + Au collisions at 1000 AMeV have been measured with an highly efficient detector hodoscope. The constructed correlation functions indicate a moderate expansion and low breakup densities similar to assumptions made in statistical multifragmentation models. In agreement with a volume breakup rather short time scales were deduced employing directional cuts in proton-proton correlations.Comment: 4 pages, with 2 included figures; To appear in the proceedings of the Bologna 2000 conference; Also available from http://www-kp3.gsi.de/www/kp3/aladin_publications.htm

Saturation current spikes eliminated in saturable core transformers

Unsaturating composite magnetic core transformer, consisting of two separate parallel cores designed so impending core saturation causes signal generation, terminates high current spike in converter primary circuit. Simplified waveform, demonstrates transformer effectiveness in eliminating current spikes

Load insensitive electrical device

A class of power converters is described for supplying direct current at one voltage from a source at another voltage. It includes a simple passive circuit arrangement of solid-state switches, inductors, and capacitors by which the output voltage of the converter tends to remain constant in spite of changes in load. The switches are sensitive to the current flowing in the circuit and are employed to permit the charging of capacitance devices in accordance with the load requirements. Because solid-state switches (such as SCR's) may be used with relatively high voltage and because of the inherent efficiency of the invention that permits relatively high switching frequencies, power supplies built in accordance with the invention, together with their associated cabling, can be substantially lighter in weight for a given output power level and efficiency of operation than systems of the prior art

Market Completion with Derivative Securities

Let $S^F$ be a $\mathbb{P}$-martingale representing the price of a primitive asset in an incomplete market framework. We present easily verifiable conditions on model coefficients which guarantee the completeness of the market in which in addition to the primitive asset one may also trade a derivative contract $S^B$. Both $S^F$ and $S^B$ are defined in terms of the solution $X$ to a $2$-dimensional stochastic differential equation: $S^F_t = f(X_t)$ and $S^B_t:=\mathbb{E}[g(X_1) | \mathcal{F}_t]$. From a purely mathematical point of view we prove that every local martingale under $\mathbb{P}$ can be represented as a stochastic integral with respect to the $\mathbb{P}$-martingale $S := (S^F\ S^B)$. Notably, in contrast to recent results on the endogenous completeness of equilibria markets, our conditions allow the Jacobian matrix of $(f,g)$ to be singular everywhere on $\mathbf{R}^2$. Hence they cover, as a special case, the prominent example of a stochastic volatility model being completed with a European call (or put) option

Saturation current protection apparatus for saturable core transformers Patent

Magnetic current regulator for saturable core transforme

New and biogeographically noteworthy records of Philippine mosses from Mindanao Island

Sixteen new records of Philippine mosses, namely, Acroporium ramicola, Atractylocarpus comosus, Campylopus flagelliferus, Ectropothecium ptychofolium, Fissidens guangdongensis, Garovaglia bauerlenii, Holomitrium stenobasis, Hypnodendron auricomum, Leucobryum boninense, Macromitrium archboldii, Meiotheciella papillosa, Neolindbergia cladomnioides, Rhynchostegiella vriesei, Schlotheimia emarginato-pilosa, Symphysodontella parvifolia and Trichosteleum singapurense are reported. Atractylocarpus and Meiotheciella are two new generic records for the country. Additional Mindanao records of five uncommon mosses in the Philippines, i.e., Claopodium assurgens, Cryptogonium phyllogonioides, Erpodium biseriatum, Meiothecium bogoriense fo tenuissima and Papillaria leuconeura, are also reported

Abelian Duality

We show that on three-dimensional Riemannian manifolds without boundaries and with trivial first real de Rham cohomology group (and in no other dimensions) scalar field theory and Maxwell theory are equivalent: the ratio of the partition functions is given by the Ray-Singer torsion of the manifold. On the level of interaction with external currents, the equivalence persists provided there is a fixed relation between the charges and the currents.Comment: 11 pages, LaTeX, no figures, a reference added, submitted to Phys. Rev.