Harnessing technology review 2008. The role of technology and its impact on education. Summary Report.

This is the summary of the second review of the use and impact of ICT in the education system following the publication of the Government's e-Strategy for education, known as Harnessing Technology. The Review drew upon Becta's surveys of schools and FE colleges as well as other research to assess the impact of technology within the education system and the progress made in achieving the system outcomes of the policy

MHD numerical simulations of colliding winds in massive binary systems - I. Thermal vs non-thermal radio emission

In the past few decades detailed observations of radio and X-rays emission from massive binary systems revealed a whole new physics present in such systems. Both thermal and non-thermal components of this emission indicate that most of the radiation at these bands originates in shocks. OB and WR stars present supersonic and massive winds that, when colliding, emit largely due to the free-free radiation. The non-thermal radio and X-ray emissions are due to synchrotron and inverse compton processes, respectively. In this case, magnetic fields are expected to play an important role on the emission distribution. In the past few years the modeling of the free-free and synchrotron emissions from massive binary systems have been based on purely hydrodynamical simulations, and ad hoc assumptions regarding the distribution of magnetic energy and the field geometry. In this work we provide the first full MHD numerical simulations of wind-wind collision in massive binary systems. We study the free-free emission characterizing its dependence on the stellar and orbital parameters. We also study self-consistently the evolution of the magnetic field at the shock region, obtaining also the synchrotron energy distribution integrated along different lines of sight. We show that the magnetic field in the shocks is larger than that obtained when the proportionality between $B$ and the plasma density is assumed. Also, we show that the role of the synchrotron emission relative to the total radio emission has been underestimated.Comment: MNRAS accepte

Harnessing technology review 2008. The role of technology and its impact on education. Full report.

This is the second review of the use and impact of ICT in the education system following the publication of the Government's e-Strategy for education, known as Harnessing Technology. The Review drew upon Becta's surveys of schools and FE colleges as well as other research to assess the impact of technology within the education system and the progress made in achieving the system outcomes of the policy

Tails of the Unexpected: The Interaction of an Isothermal Shell with a Cloud

A new mechanism for the formation of cometary tails behind dense clouds or globules is discussed. Numerical hydrodynamical models show that when a dense shell of swept-up matter overruns a cloud, material in the shell is focussed behind the cloud to form a tail. This mode of tail formation is completely distinct from other methods, which involve either the removal of material from the cloud, or shadowing from a strong, nearby source of ionization. This mechanism is relevant to the cometary tails seen in planetary nebulae and to the interaction of superbubble shells with dense clouds.Comment: 6 pages, 6 figures, accepted for publication in MNRAS letter

Becta review 2006. Evidence on the progress of ICT in education.

This is the review of the use and impact of ICT in the education system prior to the publication of the Government's e-Strategy for the education system, known as Harnessing Technology. The Review drew upon Becta's surveys of schools and FE colleges as well as other research to assess the impact of technology within the education system and the progress made in achieving Government policies in 2005-06

Becta Review 2005. Evidence on the progress of ICT in education.

Drawing on Becta national surveys of ICT use and implementation within the education system, the Becta Review identified the ways in which ICT could be used to support the DfES 5 year strategy, to introduce greater efficiencies in educational provision and more choice/personalisation of content and delivery

Harnessing technology review 2007. Progress and impact of technology in education. Full Report.

This is the first review of the use and impact of ICT in the education system following the publication of the Government's e-Strategy for the education system, known as Harnessing Technology. The Review drew upon Becta's surveys of schools and FE colleges as well as other research to assess the impact of technology within the education system and the progress made in achieving the system outcomes of the policy

The dominant X-ray wind in massive star binaries

We investigate which shocked wind is responsible for the majority of the X-ray emission in colliding wind binaries, an issue where there is some confusion in the literature, and which we show is more complicated than has been assumed. We find that where both winds rapidly cool (typically close binaries), the ratio of the wind speeds is often more important than the momentum ratio, because it controls the energy flux ratio, and the faster wind is generally the dominant emitter. When both winds are largely adiabatic (typically long-period binaries), the slower and denser wind will cool faster and the stronger wind generally dominates the X-ray luminosity.Comment: 4 pages, 1 figure, accepted by A&A Letter