Discovering the ESRF super-microscope in Grenoble. An Interview with Francesco Sette
Francesco Sette is Director General of the European Synchrotron Radiation Facility-ESRF, one of the most important international synchrotron research facilities in the world, based in Grenoble, France. In this European laboratory, set up with Italy’s important contribution, scientists investigate the secrets of matter at the atomic level to test new materials, study new drugs, analyze works of art, classify fossils, and much more. All this thanks to one of the most powerful X-ray sources existing today worldwide.
Professor Sette, what is the ESRF facility in Grenoble?
The ESRF facility is composed of a ring with a circumference of 844 metres, inside of which electrons are accelerated to speeds close to the speed of light. The deflection of these particles, induced by magnetic fields, causes the emission of a powerful source of X-rays that are 100 billion times brighter than the X-rays commonly used in hospitals. This allows us to study the structure of matter in all its beauty and complexity, with applications in many fields: from materials chemistry to medicine, from archaeology to preservation of cultural heritage.
How many researchers use your facility every year?
We receive about 2,400 experiment proposals every year and only accept less than half of them due to the time available on our 44 beamlines, each optimized for specific scientific applications. Every year, research carried out at ESRF leads to an average of 2,000 scientific publications in international journals, 300 of which in journals of excellence with an impact factor higher than 7. In addition, we welcome more than 7,000 visitors every year, and 13% of them are Italian.
Could you give us some examples of scientific research carried out at ESRF?
I could give you thousands of examples. Research carried out at ESRF has led to two Nobel prizes in chemistry: in 2009, for studies of the structure and function of the ribosome, and in 2012, for studies of G-protein-coupled receptors. But research involves a variety of sectors, including analysis of fossil remains and preservation of cultural heritage. For example, researchers from the University of Bologna managed, using synchrotron light in Grenoble, to verify the authenticity of a fossil of a semi-aquatic dinosaur found in Mongolia, which led to the identification of a new species of aquatic dinosaur. And CNR scientists succeeded in revealing the secrets of the texts written on papyrus scrolls from the Herculaneum library, buried by the eruption of Vesuvius in 79 AD.
What is Italy’s role at the ESFR facility in Grenoble?
Italy has a long tradition in the field of synchrotron light research and is one of the main contributors to the Grenoble infrastructure, together with France and Germany. Our country made a 13,2% contribution to the construction of the infrastructure and many physicists of the National Institute for Nuclear Physics had, and still have today, a key role in the project. Then we must not forget that the use of synchrotron light for experimental purposes was made possible by the invention of the first Storage Ring-AdA, designed and built at the INFN National Laboratories in Frascati by physicists Bruno Touschek, Giorgio Salvini and colleagues.
And it was at the Frascati Laboratories that you started your career
When I was writing my dissertation in physics at Sapienza University in Rome, I had the privilege, for more than one year, of being part of the group working on the PULS Project for the Use of Synchrotron Light of CNR in Frascati, which used the ADONE storage ring of the INFN as a synchrotron light source. Those years were fundamental to my education as a physicist. I then spent 8 years in the United States before moving to Grenoble in 1991, at first as a group leader and then as Director General.
What are the forthcoming developments at the ESRF facility?
We are about to start the construction of a new fourth generation machine that will multiply the performance of existing synchrotrons in terms of brilliance and coherence by a factor of 100. The new infrastructure, which should become operational in 2020, has been included in the ESFRI Roadmap 2016, which brings together the research infrastructures of pan-European interest, and stems from an idea by the Italian physicist Pantaleo Raimondi, currently Director of the Accelerator and Source Division at ESRF in Grenoble. With the project of this new machine, ESRF opens a new season in the use of X-rays for 3D microscopy at spatial resolutions of up to one millionth of a millimetre. All the synchrotron light research centres existing worldwide are now in the process of studying how to adapt Raimondi’s project to their storage rings. These facilities include the Italian centre of excellence in Trieste, the Elettra synchrotron that, featuring a 2.0/2.4 GeV accelerator, complements, in terms of beamlines and energy range, the X-rays produced by the 6 GeV synchrotron in Grenoble.