PEARL: the high pressure neutron powder diffractometer at ISIS

ABSTRACT

The PEARL instrument at ISIS has been designed for, and dedicated to, in situ studies of materials at high pressure, using the Paris–Edinburgh press. In recent years, upgrades to the instrument have led to improvements in data quality and the range of achievable pressures and temperatures; currently 0.5–28 GPa and 80–1400 K. This paper describes the technical characteristics of the instrument, its current capabilities, and gives a brief overview of the science that has been performed, using representative examples.

KEYWORDS:

• Neutron
• diffraction
• large volume press
• high pressure
• temperature
• crystal structure

Acknowledgements

This paper is written in memory of William ‘Bill’ G. Marshall who was the original instrument scientist on the PEARL instrument from 1998 to 2015, and sadly passed away in October 2015. Bill was also a member of the Edinburgh team throughout the construction and commissioning of PEARL from 1994 until 1998.

We gratefully acknowledge the help of Kevin Knight in preparation of the manuscript and contribution in many matters relating to the science programme of PEARL. We also acknowledge the contributions of Richard Nelmes, John Loveday, Rory Wilson, Malcolm Guthrie (University of Edinburgh), the late Michel Besson, Gerard Hamel, Stefan Klotz and Guillaume Weill (UPMC, Paris), and those of the ISIS facility staff: Oleg Kirichek, Chris Goodway, Mark Kibble, John Dreyer, Andy Chamberlain, Chris Barry, Steve Boon and Chris Ridley. We acknowledge Dominic Fortes, Chris Howard, and Colin Pulham for direct contribution of data in Section 6. Thanks to Simon Waller and Stephen Kill for assistance with images. We acknowledge the engineering support of Natxo Carrera of AVS, Spain and of Javier Bermejo, Madrid. Finally, we acknowledge the contributions of all those referenced within this work and those we have been unable to reference.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Funding for the initial design and build of the PEARL instrument was provided by an EPSRC Facility Development Fund and the most recent upgrade of PEARL was funded by the CSIC (Consejo Superior de Investigaciones Científicas) in Spain.