From D-Dbar Pairs to Branes in Motion

We investigate various supersymmetric brane intersections. Motivated by the recent results on supertubes, we investigate general constraints in which parallel brane-antibrane configurations are supersymmetric. Dual descriptions of these configurations involve systems of branes in relative motion. In particular, we find new supersymmetric configurations which are not related to a static brane intersection by a boost. In these new configurations, the intersection point moves at the speed of light. These systems provide interesting time dependent backgrounds for open strings.Comment: 28+1 pages, 8 figures, uses JHEP3.cl

Bound -state β- -decay of bare 205 Tl 81+

Beta decay into bound electron states of the daughter atom accompanied by the emission of a monochromatic antineutrino, has been predicted by Daudel et al.[1]. However, a noteworthy probability of βb- decay exists only for highly-charged ions, which makes its observation rather difficult

New test of modulated electron capture decay of hydrogen-like 142Pm ions: Precision measurement of purely exponential decay

An experiment addressing electron capture (EC) decay of hydrogen-like 142Pm60+ions has been conducted at the experimental storage ring (ESR) at GSI. The decay appears to be purely exponential and no modulations were observed. Decay times for about 9000 individual EC decays have been measured by applying the single-ion decay spectroscopy method. Both visually and automatically analysed data can be described by a single exponential decay with decay constants of 0.0126(7)s−1for automatic analysis and 0.0141(7)s−1for manual analysis. If a modulation superimposed on the exponential decay curve is assumed, the best fit gives a modulation amplitude of merely 0.019(15), which is compatible with zero and by 4.9 standard deviations smaller than in the original observation which had an amplitude of 0.23(4)