Design and Integration meeting: 13 October 2025 11:00 BST

Zoom: ​https://ukri.zoom.us/j/99571436156

Agenda

• Simulations.
• AOB.

Notes

Present: WS JP TJK MP
Absent: RR CW KL

• Simulations
  • MP - RL fpr nozzle , small reduction in transmission and divergence
  • TJK - thesis writing. Send fieldmap to JP for dynamic aperture studies.
  • JP - plans to re-address the dispersion issue in the stage 1 arc. Track large amplitude particles in Beamoptics. Fully evaluates the particle motion, but in a hard-edged model. Will investigate the need for sextupoles.
• AOB
  • JP: A number of issues in the CDR need correcting:
    • Pg. 8; there should be no specified number of RF cavities. There are five only in the schematic diagram, there is no physical basis for that number to be included.
    • Pg. 9; eqn 2.1 units are not correct. The E_I term should be mass, not energy.
    • Pg. 10 (2.2.3 paragraph 2); the β0 equation is wrong, the r.h.s. should be p_0 c/E_0.
    • Pg. 11 (2.3.1 paragraph 3); the Gabor lens injector for lens 1 & 2 is downstream, not upstream.
    • Pg. 13 (paragraph 1); a Wien filter should be for velocity selection, not momentum.
    • Pg. 19 (paragraph 1); eqn 2.9 should be sigma p (not sigma E), and the text immediately afterwards changed to the proton-momentum distribution.
    • Pg. 27 (paragraph 1); larger apertures can be used in the dipole so Stage 2 operation beam aperture is actually fine. The following sentences should be removed:

      The construction of a switching dipole with the aperture required to reduce beam loss to an acceptable level would not be feasible. Consequently, the LhARA injection had to be modified
      to transport beams successfully to the FFA.
      

    • Pg. 30 (paragraph 2); the Markus ion chamber volume is wrong, it should be 4.4 × 10^{-8 (missing minus sign).}
    • Pg. 31 (paragraph 2); figure 21.6 MADX dispersion is wrong. The horizontal dispersion was plotted accidentally, WS to replot with the correct vertical dispersion.
    • Pg. 32 (paragraph 2); the following text is not correct & should be removed.

      while the flexible-energy extraction made possible by the design of a flexible, efficient beam-extraction system.
      

    • Pg. 35 (paragraph 3); the emittance in the following text is not correct. The emittance cannot be optimised anyway (assumed constant) so it should be removed.

      and an emittance of ϵx,y = 99 m 
      

    • Pg. 37; table 2.14 should be removed, it's repeating 2.12. The reference to the table on page 36 should be updated to 2.12.
    • Pg. 42 (2.4.5 paragraph 2); equation β=p/E is wrong, should be β=pc/E,
    • Pg. 51 (2.5.4 paragraph 2); the following sentences are not correct & must be removed:

       The design of the FFA magnet requires the kicker magnet to bend the beam by 90◦, such a magnet is feasible is wrong.
      

      Future studies will seek to reduce the required kicker-magnet bending angle by investigating alternative configurations of the injection line and locations for the injection septum.
      

    • Pg. 173; latex reference error in table A.4 caption.
    • Pg. 184 Table B.1; the "grey shading" in the caption does not exist, it should be switched to the numbers in bold.
    • Pg. 184 Table B.1; the numbers in the table do not make sense. It's not clear if these are supposed to sum to 100% in each mode, or if discrete simulations where only one loss point is modelled with the tabulated values as the assumed losses.
    • Pg. 184 Table B.2; the caption is incorrect, it should be assumed source terms (100 Hz is not nominal).