The X5 Irradiation Facility

The irradiation facility is located downstream of the final dump of the X5 beam. It is a zone, inside which a gamma source irradiates the large detectors developed mainly for the LHC experiments, with a view to create background conditions similar to those existing in the experiments during the operation of the LHC machine. A weak muon flux from the X5 beam may be sent through those detectors and tagged by two wire chambers in between the X5 dump and the detectors to be tested. The purpose of the tests is typically to measure whether the detection efficiency and the resolution of the detectors are affected by the background radiation and if so, by how much. A system of lead filters that can be moved in fron of the source, allow the user to reduce the flux by factors up to 1000.

Layout of the radiation facility and its surroundings

The maximum size of the detectors that can be tested in this facility is 3 metres horizontal and 6 metres vertical size.
Note the present of a second collimator, allowing to irradiate crystals in a narrow cone perpendicular to the X5 beam axis.

Logfiles containing the recent history of operation of the irradiation facility are available:

• Logfile of the GIF operation,
• Logfile of the source, shutter and filter changes,
• Logfile of the X5 beam operation,
• Logfile of the beam availability in the GIF,
• Logfile of the accesses to GIF.
• Data from the GIF Common Control System.

The access to the source area is subject to special procedures, integrated in the access system to SPS experimental areas. These special procedures are described in the Gif Access Procedures.

• Technical coordination web site by M.Clayton.
• X5 User Guide for CMS ECAL calibrations in GIF.