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Magnetic reconnection occurred during merging-compression plasma start-up in the Mega Amp Spherical Tokamak (MAST), resulting in the prompt acceleration of substantial numbers of ions and electrons to highly suprathermal energies. Accelerated field-aligned ions (deuterons and protons) were detected using a neutral particle analyser at energies up to about 20 keV during merging in early MAST pulses, while nonthermal electrons have been detected indirectly in more recent pulses through microwave bursts. However no increase in soft x-ray emission was observed until later in the merging phase, by which time strong electron heating had been detected through Thomson scattering measurements. A test-particle code CUEBIT has been used to model ion acceleration in the presence of an inductive toroidal electric field with a prescribed spatial profile and temporal evolution based on Hall-MHD simulations of the merging process. The simulations yield particle distributions with properties similar to those observed experimentally, including strong field alignment of the fast ions and the acceleration of protons to higher energies than deuterons. Particle-in-cell modelling of a plasma containing a dilute field-aligned suprathermal electron component suggests that at least some of the microwave bursts can be attributed to the anomalous Doppler instability driven by anisotropic fast electrons, which do not produce measurable enhancements in soft x-ray emission either because they are insufficiently energetic or because the nonthermal bremsstrahlung emissivity during this phase of the pulse is below the detection threshold. There is no evidence of runaway electron acceleration during merging, possibly due to the presence of three-dimensional field perturbations.

The British Council in Japan, in association with the Japanese Society for the Promotion of Science, invites applications for its summer programme. This enables UK investigators in the humanities, social sciences and natural sciences to pursue collaborative research at Japanese universities and research institutes, thereby allowing them to advance their own research while promoting scientific progress in both Japan and their respective countries.

Applicants must have British nationality and be current MPhil or PhD students at a UK university. They must receive advance acceptance from a host researcher who is a full-time staff member at a university or research institution in Japan.

The awards include round trip airfare, a maintenance allowance of JPY 534,000, a research support allowance of JPY 158,500 and insurance. 18 awards are available. The fellowship duration is 12 June to 22 August 2018.

Deadline extended to 15th January 2018

The Science and Technology Facilities Council invites applications for access to the Octopus and Ultra facilities in the research complex at Harwell. The following modes of access are available in this call:

•direct access and approved access for Octopus, for work requiring access for up to four weeks in a single six-month period;

•direct access and approved access for Ultra, for work requiring access up to 60 weeks per year;

•new programme access for Octopus and Ultra.

Applicants need to provide a set of specific objectives for the project which outline scientific excellence, international competitiveness and strategic value within the STFC Central Laser Facility programme. Applications compliant with the Official Development Assistance guidelines are encouraged.

Facilities are available for use between June 2018 and November 2018. Applicants from ODA recipient countries may apply for travel and subsistence costs for investigators and collaborators.