This paper addresses one aspect of the problem of the suppression of tearing mode magnetic islands by electron cyclotron current drive (ECCD) injection, formulating the problem as the converse of a forced reconnection problem. New physical conditions are discussed which should be considered in the technical approach towards a robust control strategy. Limits on the ECCD deposition are determined to avoid driving the system into regimes where secondary instabilities develop. Numerical simulations confirming the theory are also presented.

This paper reviews key aspects of the problem of magnetic islands control by electron cyclotron current drive in fusion devices. On the basis of the ordering of the basic spatial and time scales of the magnetic reconnection physics, we present the established results, highlighting some of the open issues posed by the small-scale structures that typically accompany the nonlinear evolution of the magnetic islands and constrain the effect of the control action.

A discharge-produced-plasma (DPP) source emitting in the extreme ultraviolet (EUV) spectral region is running at the ENEA Frascati Research Centre. The plasma is generated in low-pressure xenon gas and efficiently emits 100-ns duration radiation pulses in the 10–20-nm wavelength range, with an energy of $20~\text{mJ}/\text{shot}/\text{sr}$ at a 10-Hz repetition rate. The complex discharge evolution is constantly examined and controlled with electrical measurements, while a ns-gated CCD camera allowed observation of the discharge development in the visible, detection of time-resolved plasma-column pinching, and optimization of the pre-ionization timing. Accurately calibrated Zr-filtered PIN diodes are used to monitor the temporal behaviour and energy emission of the EUV pulses, while the calibration of a dosimetric film allows quantitative imaging of the emitted radiation. This comprehensive plasma diagnostics has demonstrated its effectiveness in suitably adjusting the source configuration for several applications, such as exposures of photonic materials and innovative photoresists.

A total of 701 comets received names between July 2005 and June 2008. Comets observed only from the SOHO and STEREO missions, as well as further comets recognized from the long-defunct SOLWIND satellite, accounted for 520 of these names.

After a brief discussion it was agreed that this membership is well distributed in terms of geography, gender, and fields of planetary work.

As for comets 619 comets received names from July 2002 to June 2005. Of this naming 76 percent are SOHO comets and 11 percent include the name of the LINEAR project. A revision of the guidelines for naming comets has been completed in March 2003. The assistance of the director of CBAT, Daniel W. E. Green, in redrafting these guidelines was much appreciated by the committee.

The past triennium has continued to see a huge influx of astrometric positions of small solar system bodies provided by near-Earth object (NEO) surveys. As a result, the size of the orbital databases of all populations of small solar system bodies continues to increase dramatically, and this in turn allows finer and finer analyses of the types of motion in various regions of the orbital elements space.

The spatial shaping of light beams is the process of redistributing the irradiance of a light beam. A correct beam shaping is essential to optimize a large number of laser-material processing applications and laser-material interaction studies. In this paper, after introducing the basic equations of the classical beam integration method to reshape and homogenize laser beams, we detail the design elements, the experimental performance and the main parameters of a novel transfocal homogenizer that is able to homogenize and reshape any light beam. Then we discuss the reliability of existing international standard parameters to evaluate the “goodness” of nearly flat-top shaped laser beams. Finally, we present examples of successful applications of this new homogenizer technology to ultraviolet irradiation experiments.

New easy spectrally tunable backlighting schemes based on a spherically bent crystal are considered. Contrary to traditional backlighting scheme, in which the investigated objects should be placed between the backlighter and the crystal, for the considered schemes an object is placed downstream of the crystal, before the tangential or after the sagittal focus and an image of the object is recorded at the distance from the object corresponding to the needed magnification. The magnification is defined by the ratio of the distances from the sagittal focus to the detector and from the object to the sagittal focus. A ray-tracing modeling and experimental images of test meshes, obtained at incidence angles of the backlighter radiation of 10° and 22°, are presented. It is demonstrated that a simple linear transformation of the obtained astigmatic images allows reconstructing them as a stigmatic with an accuracy of 5–15%. For the spectral range around 9 Å a spatial resolution about 10 μm in a field of view of some square millimeters is achieved experimentally and confirmed by ray-tracing simulations.