Long-Term Visitors

The ILL receives visitors from external organisations who spend extended periods of time on the site, collaborating on research activities, exchanging scientific and technical knowledge, or on an exchange visit from a partner research centre. The ILL acknowledges the benefits that long-term visitors bring to the Institute and is keen to ensure that their working conditions enable them to perform well in their job and allow them to develop both professionally and socially for the benefit of both their employer and the ILL.

The ILL welcomes several categories of Long-Term Visitor to the ILL. Most visitors are involved in the scientific and technical life of the institute in the following ways:

• Scientists, engineers and technicians from neutron research laboratories world-wide, but especially from Associate and Scientific Member countries, collaborating on experimental facilities and technical developments, and/or working on experiments that take many months to complete.

• Scientists on sabbatical leave from universities who spend an extended period in the active research environment of the ILL to carry out a prepared scientific programme free from their regular teaching or administrative duties.

• Members of Colllaborative Research Groups (CRG) and Externally Funded Initiatives (EFI), building and/or operating CRG or EFI facilities at the ILL.

• PhD students from partner universities for whom a major part of their research is based on experimental results obtained at ILL.

• Post-doctoral research scientists acting on behalf of ILL user groups based in partner universities.

• Engineers and computer experts working on specialised projects for the development of new techniques or infrastructure.

The ILL recognises that these scientific collaborations globally benefit the ILL by contributing to the scientific life and reputation of the institute and by helping to establish mutually beneficial relationships with other national or international research organisations.

Long-Term Visitors represent a significant fraction of the scientific and technical personnel who work at ILL, but are not employed by the ILL. They are however, consumers of vital and limited resources (office space, computing facilities, technical resources) provided by the institute. The ILL therefore wishes to ensure that host facilities are only granted to candidates who fulfil the main objective of their stay – to contribute significantly to the scientific and technical life of the institute.
The criteria for granting LTV status can be met in a number of ways:

  • via a contractual agreement between ILL and the visitor’s employer, as in the case of CRGs and EFIs,
  • via an agreement between ILL and a Partner Institution (the employer) to exchange and/or combine experience and know-how in the development of new technologies, facilities or projects or for a specific research activity,
  • through an invitation from a senior ILL staff member (Director, Head of Service or Instrument Group Leader) to further scientific research or technical development,
  • as part of an agreement between ILL and a Partner Institution for the training of PhD students or young scientists,
  • as part of a scientific or educational programme funded by the European Union,
  • LTV status will only be granted for continuous periods of stay of more than 3 months. It will not be granted for repeated visits of less than 3 months interrupted by periods of absence, even when the total duration of the visits exceeds 3 months. For interrupted visits of this kind, temporary access can be granted for each visit. LTV status is granted for a maximum of 12 months, which may be renewed for further 12-month periods.

LTV status may be subject to the availability of suitable office space and other facilities, and in particular the ILL may wish to postpone visits at times when such facilities are temporarily in short supply, such as during periods of major reconstruction. Institutions intending to send staff to ILL should check with the appropriate Instrument Group Leader or Head of Service that LTV status is likely to be granted for the period requested and that they will meet the conditions laid down below.

Duration of the stay

LTV status will only be granted for continuous periods of stay of more than 3 months. It will not be granted for repeated visits of less than 3 months interrupted by periods of absence, even when the total duration of the visits exceeds 3 months. For interrupted visits of this kind, temporary access can be granted for each visit. LTV status is granted for a maximum of 12 months, which may be renewed for further 12-month periods.

First-time applications must be made at least TWO MONTHS before the start of the intended stay using the ILL form Long-Term-Visitor Application (available also in French). Applications for renewal must be made before the previous authorisation expires. Applications must be accompanied by a valid certificate of medical fitness (see below) for work under ionising radiation if access to the ILL experimental areas is required. By signing the LTV form, the institution sending the LTV to ILL certifies that the employee has insurance covering personal accident and accidental damage to ILL facilities and third parties, valid for the full duration of the stay.

Administrative requirements

Non-French visitors must be in possession of a valid passport and for certain non-EC nationals they will need to apply for a special visa (visa scientifique). They should contact  ILL administration two months before their arrival to obtain a special form (convention d'accueil) in order to apply for the visa for themselves and for adult members of their family. On their arrival in Grenoble they will be required to apply for a French residence permit (carte de séjour). They may also need to apply for a French driving licence.

Safety information

LTVs are required to attend a one-day safety-training programme, covering radiation protection, fire and other risks. The ILL is obliged to withdraw LTV status from visitors who repeatedly fail to attend the safety training.

Medical requirements

If LTVs wish to access the experimental areas, they are required to have a valid medical certificate issued by their work medical service or an approved body.>

Employment status and accident insurance

The ILL requires that all LTVs working at the ILL, and especially those granted access to experimental areas, must be insured against personal accident and third party accidental damage. The visitor’s employer is legally responsible for ensuring that such insurance is valid. Visitors whose employment conditions change significantly (or who change their employer during their stay) must reapply for LTV status.

Social welfare

An essential condition for granting LTV status is that visitors, their families and/or companions have full access to social and medical services in France under similar conditions to those of ILL staff. European Community nationals employed in their own country before being detached to ILL are entitled to basic social welfare in France. Non-EC nationals are entitled to social welfare in the EC country where they are employed, but this welfare cover may not be transferable to France. Examples of cases where problems have arisen are given here. Employers of LTVs are also strongly encouraged to provide for complementary medical insurance (Mutuelle) to supplement state medical benefits. You may find the Kastler Foundation website useful.

Resources to be provided by the employer

In order to fulfil the objective of contributing to the scientific life of the ILL, LTVs often need other resources that are sometimes overlooked. These may include computer hardware and software, and funds for a number of purposes: travel and conference fees, samples for experiments, technical support, books and journals, and the use of telephones. Funds for these needs should be considered in advance and incorporated into the agreement, before the visit begins. It cannot be assumed that the ILL will take on these, often significant, costs.

Social Welfare

The most common problems encountered by LTVs coming to ILL are related to social welfare, which cannot always be transferred between European countries. These particularly concern non-French staff and their families and companions and are best explained by example.

  • A CRG whose main employer is based in Germany employed an Italian scientist to work in at ILL France. The Italian scientist had never actually worked in Germany, and was refused German social welfare to work in France. Unable to find a solution and faced with mounting health costs, the employee left his post and engaged legal proceedings.
  • A British organisation recruited a non-European scientist in the UK who had enjoyed full social welfare there for himself and his family. This British welfare can be transferred to another EC country for EC nationals, but is not valid for non-EC nationals. The scientist and his family came to France without being aware that their welfare status was lost.

These welfare problems can be overcome by registering the company as employing staff to work in France. Information can be found here.

One should note however that the employee’s social contributions in France are much higher than in the UK, and that temporary employment contracts in France cannot currently exceed 18 months, whereas many such contracts with non-French CRGs or EFIs are for periods of up to 3 years.

You may find also the Kastler Foundation website useful.


You may find it helpful to contact L'Espace Information / Accueil chercheurs on the campus as they provide a variety of free services and information.

Services de Santé au Travail Interentreprises

Official agencies dealing with health and safety issues in the workplace


35 rue Gustave Eiffel

38000 Grenoble

Tel: 04 76 48 05 54

Fax: 04 76 48 47 20

15 rue des Colibris

38100 Grenoble Cedex

Tel: 04 76 40 09 09

Fax: 04 76 22 77 95

17 rue Jean Jaurès

38170 Seyssinet-Pariset

Tel: 04 76 48 90 00

Fax: 04 76 84 09 26