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For any question about:

The answers will be grouped together by topic and published in this Frequently Asked Questions page.


What is the ILL's mission?

The ILL is a service facility. Its purpose is to provide the international scientific community with the brightest beams of neutrons possible.

Most of its neutron beams are used to probe materials.  The fields of investigation range from technology applications to biology and health.

Neutrons hold the key to many important questions related to the fundamental laws governing our universe.  They are also themselves objects of great scientific interest.

What is a neutron?

Neutrons are neutral elementary particles that have about the same mass as a hydrogen atom.

Due to their lack of charge they can penetrate deeply into matter; this allows scientists to use them to examine the properties of materials in a non-destructive fashion.

What do neutrons tell us?

Neutrons interact with the nuclei of matter.  By observing how they are deviated and how they change speed we obtain precise information about the position and the motion of the nuclei.

They also behave like small compass needles and can provide unique insight into magnetism. [more]




How does this knowledge benefit society?

Modern societies are technology driven. Progress in many scientific areas depends on understanding materials at their molecular level, whether we are interested in the components of an electronic circuit, the membranes and contacts of a fuel cell or battery, or proteins in a biological cell. Neutrons often provide decisive information for developing applications.

Can this knowledge be obtained in a different way?

Modern science possesses a variety of methods to investigate the structure and dynamics of materials.  Each of these has its own strengths and weaknesses.

Neutrons have a number of unique advantages, including amongst others their high penetrative power and sensitivity to magnetic fields. These make them an indispensible tool for the study of matter. Without neutrons the scientific community would simply be blind to some of the phenomena in the microcosmos.

It is the outstanding observation capacities of neutrons that justify the investment being made into neutron facilities. Capital investment in the ILL amounts to almost 2 billion euros; the Institute has an annual budget of about €80m.

Who uses the ILL?

The experiments performed at the ILL are chosen following a highly competitive selection process involving international experts. The ILL receives almost 1500 requests for access to neutron beamtime every year. We are only able to accept about half of these.

About 1500 researchers travel to the ILL every year from all over the world to perform experiments.

Where does the money come from?

The ILL is an international facility.

It is run by its Associates, the three founding countries Germany, France and the United Kingdom. Each of the founding countries contributes about 25 % to the annual budget.

The remaining funding is provided by the 12 Scientific Members (Spain, Switzerland, Austria, Italy, the Czech Republic, Sweden, Hungary, Belgium, Slovakia, Denmark, Poland, and India).

The ILL thus caters to more than 90 % of the European neutron scattering community.

The ILL provides a showcase for a Europe collaborating successfully through the promotion of science and intercultural relations.

Are there other neutron facilities in the world?

Given the importance of neutrons, it is not surprising that there is a highly competitive network of neutron facilities all over the world. Apart from the ILL, France possesses a neutron source at the LLB in Saclay.

The ILL has flagship status among neutron facilities. It offers the brightest neutron beams over a wide range of energies. As the world leader in neutron scattering the Institute plays a leading role in promoting the scientific reputation of the Grenoble region

How is the ILL retaining its world-leading position?

It is one of the ILL's missions to provide  the scientific community with innovative instrumentation for neutron science. The ILL is therefore continuously monitoring and developing neutron transport and neutron detection techniques, whilst upgrading its own facilities in the process.

Its most recent modernisation campaign involved more than €50m in investment and has resulted in over a 19-fold increase in performance. The neutron source itself is of such ingenious design that it seems difficult to improve on it further.

Why does the ILL need a nuclear reactor?

All the neutrons on earth are bound in nuclei. Some of these nuclei are unstable, and they free up neutrons when they decay. This is the case of uranium, used in the ILL reactor. In commercial power plants the decay process is exploited to produce energy. At the ILL the reactor is used to extract neutrons from uranium nuclei for scientific exploitation. This explains the small size and overall design of the ILL reactor. [more].

Are there alternative ways of producing neutrons?

Neutrons can also be obtained by bombarding heavy nuclei like mercury with protons. This produces a pulsed beam of neutrons and has its advantages. Up to now however these so-called spallation sources do not compete with the ILL in terms of total flux. This will only be the case for the  ESS (investment cost of €1.5 billion), which in not expected to become fully operational before 2025. The ILL will therefore remain indispensible to European neutron users for many years to come.

How does Grenoble contribute to the ILL's success?

Grenoble has a plethora of excellent research institutions and universities, and therefore offers ideal conditions for fruitful scientific collaboration. Despite its strong international ties, the ILL owes a great deal to its neighbouring institutions. For a broader view, have a look at the website of GIANT.

Grenoble also offers an ideal environment and good facilities for foreign visitors and staff, and this brings dividends in return for the local economy and culture.

How does the ILL contribute to the development of science in Grenoble?

The ILL was the historical nucleus of what has today become the European Photon and Neutron Science Campus. The epn science campus is now also home to the European Synchrotron Radiation Facility (ESRF) and an outstation of the European Molecular Biology Laboratory (EMBL). The siting together of complementary scientific installations with a view to harnessing their combined potential is a model that has found followers worldwide.

With more than 6000 visitors per year the  epn campus brings a strong international dimension to science in Grenoble.

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