Derek Seguin and Chad Anderson grow the generation gap when they discuss if Gen Xers are the best age group. Then, Hisham Kelati and Kathleen McGee have a spirited debate on whether angels are superior to ghosts.

An analysis of the coherence properties of the fourth-generation high-energy storage rings with emittance values of 10 pm rad is performed. It is presently expected that a storage ring with these low emittance values will reach diffraction limit at hard X-rays. Simulations of coherence properties were performed with the XRT software and an analytical approach for different photon energies from 500 eV to 50 keV. It was demonstrated that a minimum photon emittance (diffraction limit) reached at such storage rings is λ/2π. Using mode decomposition it is shown that, for the parameters of the storage ring considered in this work, the diffraction limit will be reached for soft X-ray energies of 500 eV. About ten modes will contribute to the radiation field at 12 keV photon energy and even more modes give a contribution at higher photon energies. Energy spread effects of the electron beam in a low-emittance storage ring were analysed in detail. Simulations were performed at different relative energy spread values from zero to 2 × 10−3. A decrease of the degree of coherence with an increase of the relative energy spread value was observed. This analysis shows that, to reach the diffraction limit for high photon energies, electron beam emittance should go down to 1 pm rad and below.

Generation Xers accounted for half of all the people that died in smoking related fires and a third of injuries, according to new data from London Fire Brigade.

MOST150 Technology to Control the Infotainment System on Volvo Cars’ Second-Generation XC60 SUV

In a stunt worthy of the latest Bond film Spectre — for which the firm is supplying many of the cars — the XF (pictured) was revealed in a dramatic stunt high over the Royal Dock in Canary Wharf.