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. Five is only in the schematic diagram & has no physical basis for being that number.
    • 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, 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, and the text immediatley 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. WS believes the wrong axis is plotted. WS to replot with the right axis for 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 follwoing 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, WS thinks it should be switched to the numbers in bold.
• Pg. 184 Table B.1; the numbers in the table do not make sense. Are these supposed to sum to 100% in each mode, or do the tabulated values represent discrete simulations where only one loss point is modelled?
• Pg. 184 Table B.2; the caption is incorrect, it should be assumed source terms (100 Hz is not nominal).