CERN — The European Laboratory for Particle Physics



You can access IMPACT at the following link: 

An Impact form must be filled for each visit.
Once you sent your request to, the LHCb Secretariat will prepare a template for you, in which you might need to add further information. To access your prepared Impact form, please open a link on  followed by ?activity=NNNNN, where NNNNN is the impact number (e.g for Impact 37408 do Make sure that guide(s) are listed, the number of visitors per guide is respected, the total number of participants (guides + visitors) is correct, gsm number is available and click on the submit button (status will change to "waiting for approval").

If you want to create the Impact form by yourself, please duplicate the existing modele for template : 37408 and please refer to the instructions below.

After the visit you will need to fill the Report sections of the Impact form, please refer to the instructions below.


1. Before the visit fill the request sections of the access form in IMPACT

The heading of the form:

Title: e.g.  Visit to …. by
Responsible: the responsible of the visit is also the supervisor of the visit. (This person has to be a member of LHCb).
Please note that only the supervisor of the visit and the creator of the form are allowed to modify it later.
Facility:  LHCb
Activity type:  Visit

Then fill in WHAT, WHEN, WHO, WHERE and HOW


Description : a short description of the purpose of the visit
System: choose  LHCb -> Other  for visits at the moment (the option “Visit” will be added in the near future)


Click Add a participant:
Start with the supervisor of the visit (=the responsible for the visit) – the system will automatically look for the full name and other details on the person if he/she is in the CERN database.

Fill in the details on guides. Please note that the supervisor can also be a guide and have two roles . If this is the case, his/ name should be mentioned twice in both roles.

Max  Nb of participants: total for all group, including guides - Max Nb. of visitors per group is 10

Contact phone (mandatory): the phone number of the guides where they could be reached during the visit


Fill the first three lines and modify line 5, 'Working time Start and 'Working time End' to give a time frame when you will do the visit (e.g. 17:00 to 18:30) or put it in the comment line. Always fill in the "Proposal" date as it is used for overview scheduling.


Choose LHCb - > LHCb visit


Modus Operandi (mandatory) : Description of the visit route e.g. Delphi  and LHCb visit

For your visit to be visible on the list of LHCb future visits, make sure you select "LHCb Underground Private visits" under tags at the bottom.

Then save, and when the request is completed, submit the document.


2. After the visit fill the Report sections of the IMPACT form (to be filled by the supervisor)

Put the outcome of the visit or problems encountered. e.g. Visit was successful
Verify the total number of participants is correct or adjust it (if no show for example)

You can then declare the visit "finished" by clicking on the "Close" button on the top right menu .