AIRIS Design Parameters


The three main components of AIRIS include a momentum achromat, an RF sweeper, and a buncher/rebuncher resonator. The design considered a number of variables, including large transmission and acceptance of secondary beams produced in-flight, suppression of the unreacted primary beam, and allowance for stable beam tunes through the device when it is not in use.

Information on each sub-section is below.

Momentum Achromat

A block diagram of the magnetic chicane, which resides between two sets of quadrupole doublets, is shown below along with a table of detailed paramters.

Magnetic Layout

ParameterValueUnits
Total Length6.6m
Angular Acceptance75mrad
Momentum Dispersion at Mid-Plane1.2mm/%
Dipole Bend Angle22.5degrees
Dipole Radius1m
Dipole Full Gap8cm
Dipole Max Field1.75T
Quadrupole Full Aperture15cm
Quadrupole Length20cm
Quadrupole Max Field1T

Buncher/Debuncher Resonator

Bunching or Debunching of the secondary beam can be performed by a superconducting cavity. The parameters of the cavity used for the design and transmission calculations are below.

ParameterValueUnits
Aperture3.8cm
Frequency72.75MHz
Maximum Voltage3MV
Cavity Beta0.075

RF Sweeper

The RF sweeper provides contaminant beam reduction through velocity differences (time-of-flight separation). The parameters below have been used in the design and transmission calculations are below. They are based on the current ATLAS operating sweeper.

ParameterValueUnits
Electrode Length1m
Frequency6.0625MHz
Maximum Voltage70kV