Beam Line Description

The Beam Line

The CLEAR facility is hosted by the CLEX experimental area at CERN - building 2010. The CLEAR Beam Line is built on the basis of CALIFES, previously used at CTF3 as Probe Beam injector for testing the CLIC Two Beam Acceleration concept.

On the spectrometer at the end of the CALIFES injector is placed the VESPER (see its official web page): a test stand for irradiation studies.

The layout of the linear accelerator and VESPER is as follows:
CLEAR Injector Layout

The 2nd part of the line, which contains most of the experiments:
CLEAR Experimental Area Layout

Technical Drawings of the facility are available on request.

Beam Parameters

The beam parameters at the end of the linac are summarised in the following table:

Beam parameter (end of linac) Value range
Energy 130 - 220 MeV (down to 60 MeV with upgrade)
Bunch charge 0.01 - 0.5 nC
Normalized emittances 3 um for 0.05 nC per bunch
20 um for 0.4 nC per bunch (in both planes)
Bunch length ~500 um -1.2 mm
Relative energy spread < 0.2 % rms (< 1 MeV FWHM)
Repetition rate 1 - 5 Hz (25 Hz with upgrade)
Number of micro-bunches in train 1 and more than 100
Micro-bunch spacing 1.5 GHz

Beam line MAD-X Lattice

The MAD-X sequence of the present beam line is available on the official CERN Gitlab Optics Repository.