The ILL is determined to help its visiting researchers make the most of its facilities.
Europe has a community of about 5000 scientific neutron users and the demand for ILL beamtime is high and rising.
In 2006 for example the ILL welcomed a total of about 2000 visitors in 2006. Approximately 87% came from the member countries.
The Scientific Coordination Office (SCO) provides the framework to help researchers access ILL instruments.
The Visitors Club is a fully electronic communication portal for the ILL user community.
Application for beamtime is organised electronically, via the Visitors Club website. Proposals can be submitted to the ILL twice a year, usually in February and in September. The web system is activated two months before each deadline.
There are normally 4 reactor cycles yearly, each of which lasts 50 days. Successful proposals submitted by February will receive beamtime in the second half of the year; those submitted by September receive beamtime in the first half of the following year.
A typical team of users consists of two to five scientists, often from two or three different laboratories. The ILL reimburses the travel and accommodation expenses for up to two scientists per experiment. Additional reimbursement may be possible with SCO authorisation for work on very 'user-demanding' experiments.
Only researchers belonging to the ILL member countries are entitled to reimbursement. Scientists affiliated to laboratories in Poland, however, are not reimbursed although they have recently joined the ILL. They have scientific affiliation guaranteeing them beamtime and exempting them from the rules on national balance. Their contribution is lower than 1.5%.
Reliability of the ILL reactor
Reactor-based neutron sources are significantly more reliable than pulsed spallation sources for example.
The graphic below illustrates the level of reliability of the ILL reactor:

Use of ILL beamtime
On average, about 80% of the total days of operation is made available to our users.
Of the remainder, about 5% is used by ILL scientists to carry out their own research and about 10% is allowed for tests, calibrations, flexibility and the retrieval of time lost to minor breakdowns.
On average, less than 6% of the total beamtime available on ILL instruments is lost due to various malfunctions, as reported below: