Low-Q2 Tagger weekly meeting

Tuesday 19 Aug 2025, 08:00 → 09:00 US/Eastern

Zoom link: https://uofglasgow.zoom.us/j/87250812954?pwd=NlY4QmJhaTJCdlV0cUUvUnV6dXVJdz09

Passcode: 754613

 

Live Notes

08:00 → 08:15 Collaboration WG updates

Updates and news from meetings and other discussions in the last week.

Speakers: Jaroslav Adam (Czech Technical University in Prague), Dr Simon Gardner (University of Glasgow)

08:15 → 08:35 Beamline magnet updates

Speaker: Dr Andrii Natochii (Brookhaven National Laboratory)

2D field maps.zip

B2AeR_3D_approx - STEP file

B2BeR_3D_approx - STEP file

B2BeR_Yoke.png

b2er-asm

B2eR_magnets.png

ESR Far-BWD Beam Losses (Coulomb, Touschek, Brems) v6.3.1 lattice with collimators

esr-ip6-10GeV.tfs

esr-ip6-18GeV.tfs

esr-survey-tilt_20250723.tfs

• On August 18, 2025: Karim Hamdi (IR6 system integration contact) informed us about a new design for the B2eR magnets (B2AeR and B2BeR) prepared by Harshita Singh (ESR magnet designer); please see the attachments.
• Since the antechamber appears to be positioned quite close to the magnet yoke, the experts wonder if the current beam pipe design is still applicable.
• To address this question, one needs to study the acceptance of the taggers for low-Q² electrons. It might be possible to taper the antechamber near the magnet side, as electrons have some divergence and are unlikely to travel that close to the yoke in the horizontal plane.
• Surprisingly, the antechamber fits within the magnet, considering we originally designed it without knowing the magnet dimensions. This might be a good opportunity to optimize the design. For example, we could consider extending the antechamber closer to the IP (from B2BeR up to B2AeR) to potentially improve the tagger’s acceptance. 
• And of course, then we should confirm with the magnet experts whether the antechamber can be placed inside the magnet, as there could be a concern about possible magnetic field distortions caused by the beam pipe’s asymmetry.

08:35 → 08:55 Low-Q2 benchmarks

Speaker: Dr Simon Gardner (University of Glasgow)

LowQ2-Meeting-Benchmarking.pdf