As proposed in 1979 1 , standing waves of polychromatic laser light can trap atoms, molecules or larger particles to provide a free-standing reflective optical surface. Such mirrors must be fabricated in space and may in principle reach sizes beyond 10m, using techniques related to optical tweezers and atom traps. Laboratory testing in vacuum tanks is becoming possible. Diode lasers having adeq...

A concept for a charge state multiplier, to be used for the production of energetic radioactive ion beams based on the ISOL+post-accelerator system, is discussed. The charge state breeder implies external ion injection into an Electron Beam Ion Source (EBIS). The total efficiency, measured by injecting a low-energy nitrogen (Q=1+ ) beam, reached 14.5% and was essentially constant for confinemen...

The interaction of short and intense laser pulses with plasmas is a very efficient source of relativistic electrons with tunable properties. In low density plasmas, we observed bunches of electrons up to 200 MeV, accelerated in the wake field of the laser pulse. Less energetic electrons (tens of MeV) have been obtained, albeit with a higher efficiency, during the interaction with a solid target...

The energetic cost of acoustic signalling varies tremendously among species. Understanding factors responsible for this heterogeneity is important for understanding the costs and benefits of signalling. Here, we present a general model, based on well-established principles of bioenergetics, which predicts the energetic cost of call production across species. We test model predictions using an e...

Energy expenditure was measured during pregnancy in seven primigravid women at 12-15, 25-28, and 34-36 weeks and after the cessation of lactation. On each occasion the resting metabolic rate and the increase in metabolic rate after ingestion of a liquid test meal were measured by indirect calorimetry. In absolute terms the resting metabolic rate increased steadily during pregnancy but when expr...