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This paper presents an e ective methodology to assess the safety of aircraft operations when aero- drome obstacle standards cannot be met. The re- search addresses the cases of potential airplane impact with on-ground obstacles after an engine failure. The discussion focuses on how statistical studies can be supported by deterministic analy- ses of flight trajectories generated with 6 degree- of-freedom (6DoF) flight simulations. The pro- posed approach is illustrated by introducing a practical example coming from the authors’ pro- fessional experience; in the selected scenario a hypothetical wind farm has to be located in prox- imity of an aerodrome but some of the wind tur- bines intrude the conventional airspace required by ICAO to ensure safe and regular aircraft op- erations. The paper presents the relevant safety requirements applicable around airports and in- troduces a preliminary evaluation technique of the theoretical collision risk (CR) based on the open source flight dynamics model (FDM) soft- ware JSBSim. Finally, a Monte Carlo analysis is presented as an additional step to refine the CR assessment.

An experimental campaign to perform the first accurate measurement of the 17O(a,g)21Ne reaction rate was carried out during May and November 2009 at the DRAGON recoil separator in the TRIUMF laboratory, Vancouver, Canada. The goals were to differentiate between two previous conflicting theoretical predictions, and to establish the (a,g)/(a,n) reaction rate ratio.Two distinct energy regions were scanned: a higher region, Ecm 1.5 MeV, where the recoil cone was sufficiently confined and the cross section sufficiently large so that a statistically significant yield could be achieved, and a lower region, Ecm 0.7 MeV, chosen to approach the astrophysicalenergies and reduce errors from extrapolation. The experiment, performed in inverse kinematics, used the highest intensity beam ever deliveredto DRAGON, 11012 pps of 17O incident on a 4He gas target. An array of 30 Bismuth Germanate (BGO) detectors [1] was used in conjunction with two microchannel plates (MCP) [2] for a local time-of-flight measurement, and ion chamber for coincident event detection.

Green-leaf volatiles are commonly emitted from mechanically and herbivore-damaged plants. Derived from the lipoxygenase pathway, these compounds may serve as attractants to predators and parasitoids of herbivores, prevent the spread of bacteria and fung

The heavy-ion radiative capture reaction, 12C(12C,$\gamma$), has been investigated at energies both on- and off-resonance, with a particular focus on known resonances at Ec.m.=6.0, 6.8, 7.5, and 8.0 MeV. Gamma rays detected in a BGO scintillator array were recorded in coincidence with 24Mg residues at the focal plane of the DRAGON recoil separator at TRIUMF. In this manner, the relative strength of all decay pathways through excited states up to the particle threshold could be examined for the first time. Isovector M1 transitions are found to be a important component of the radiative capture from the Ec.m.=6.0 and 6.8 MeV resonances. Comparison with Monte Carlo simulations suggests that these resonances may have either J=0 or 2, with a preference for J=2. The higher energy resonances at Ec.m.=7.5 and 8.0 MeV have a rather different decay pattern. The former is a clear candidate for a J=4 resonance, whereas the latter has a dominant J=4 character superposed on a J=2 resonant component underneath. The relationship between these resonances and the well-known quasimolecular resonances as well as resonances in breakup and electrofission of 24Mg into two 12C nuclei are discussed.

Emission of methylsalicylate (MeSA), and occasionally of methylbenzoate (MeBA), from Arabidopsis thaliana leaves was detected following the application of some forms of both biotic and abiotic stresses to the plant. Maximal emission of MeSA was observed

Physical Review Letters

The shape of the low-energy part of the β-delayed α-particle spectrum of 16N is very sensitive to the α+12C reduced width of the 7.117 MeV subthreshold state of 16O. This state, in turn, dominates the low-energy p-wave capture amplitude of the astrophysically important 12C(α,γ)16O reaction. The α spectrum following the decay of 16N has been measured by producing a low-energy 16N14N+ beam with the TRIUMF isotope separator TISOL, stopping the molecular ions in a foil, and counting the α particles and 12C recoil nuclei in coincidence, in thin surface-barrier detectors. In addition to obtaining the α spectrum, this procedure determines the complete detector response including the low-energy tail. The spectrum, which contains more than 106 events, has been fitted by R- and K-matrix parametrizations which include the measured 12C(α,γ)16O cross section and the measured α+12C elastic scattering phase shifts. The model space appropriate for these parametrizations has been investigated. For SE1(300), the E1 part of the astrophysical S factor for the 12C(α,γ)16O reaction at Ec.m.=300 keV, values of 79±21 and 82±26 keV b have been derived from the R- and K-matrix fits, respectively.

The overall objective of the workshop was to allow prospective users of the proposed ISAC (Isotope Separator and Accelerator) Exotic Beams Facility, proposed for installation at TRIUMF, to discuss the scientific opportunities with accelerated radioactive beams, to ensure that the specifications which are being used to design the facility are appropriate to perform forefront research, to allow scientists with experience using such facilities to share their knowledge, and to provide an open forum to discuss in detail the types of experimental facilities needed at ISAC.