BIPXL - BiWeekly Meeting

Friday 29 Aug 2025, 14:00 → 15:00 Europe/Zurich

865/1-B03 (CERN)

meeting_saved_closed_caption.txt

BIPXL jira kanban board: https://its.cern.ch/jira/secure/RapidBoard.jspa?projectKey=BIPXL&rapidView=9072

---

Follow-Up from last meeting

• MD data results & comparison plots.
  • See https://its.cern.ch/jira/browse/BIPXL-120
• Status of PS horizontal diagnostics or replacement decision.
  • See https://its.cern.ch/jira/browse/BIPXL-61
  • Seems to bo some thermal/radiation effects only visible in the PS
• GBTX configuration reliability improvement.
  • Solved with updates to the config in the internal driver
  • 4.1.3-release
  • 4.1.2-release
• Telescope deployment progress & initial timing validation.
  • See https://its.cern.ch/jira/browse/BIPXL-82 and https://its.cern.ch/jira/browse/BIPXL-62
• Event rate investigation findings.
• DMA / driver integration status.
  • See https://its.cern.ch/jira/browse/BIPXL-161

---

Minutes

Date: 29/08/2025

Participants: James, Mark, Steen, Hampus, Juri, Lukas (Zoom), Gabriela (Zoom)

Key Technical Updates

• Timing & Synchronization: Current telescope timestamps limited to ±100 ns. TimeWalk correction demonstrated (~10 ns residual). SPS bunch-by-bunch requires <25 ns precision. Next step: SPS BGI calibration using single LHC bunch (1 x 5ns bucket filled) or in the future electron gun.

• HL-LHC Beam Profile Review (23 Sept): BI contribution: 20-min BGI talk (James) on design, performance, and PS/SPS experience. Results needed before Lukas’ holiday.

• Telescope: Detector correlations now clear; track χ² improving with ongoing software alignment. Next: reference crystal installation + multi-volume crystal tests.

• DAQ/FESA Stability: Occasional crashes during MD runs (likely data-volume related). Stable in command-line mode; monitoring continues.

• Hardware / Optics: Broken fibre in telescope channel traced to installation; procedure should be documented. GBTx configuration improved significantly and seems stable now in 4.1.3-release branch.

• SPS BGI Vertical: Raw data path non-functional; likely SFP/module issue. Plan: retest in lab post-run with validated SD cards and spares.

Strategic / Forward Planning

• PCIe/DMA Support: Ongoing difficulties with Edge + XDMA drivers. Options:

  1. Investigate Edge 2.1 compatibility.

  2. Fallback to commercial PCIe cards with supported DMA drivers.
     Decision required within 2 weeks to ensure 2026 PS/SPS BGI readiness.

• PS Horizontal BGI: Persistent no ionization electron problem. Decision: build new instrument from existing spares; test and qualify before LS3.

• PS BGI Front-Ends: Failing after minutes due to (probably) thermal problem. Hampus & Wilfried to implement solution with fan. Radiation damage to DC fans could be an issue.

• SPS Shields: Horizontal now robust with RF shield. Vertical shield upgrade under study (diamond or smaller-hole variant). Decision point: end November. Possible MD to test shield options.

Acknowledgement

• Farewell to Gabriela (final day). Team expressed gratitude for her 3 years of valuable contributions.

 

---

Follow-up next meeting

• Prepare BGI results for HL-LHC review (Sept 23).

• Build new PS horizontal BGI instrument.

• Prepare alternative SPS vertical shield (diamond-type).

• Standardize fibre installation procedures.

• Continue monitoring FESA crashes.

• Finalize PCIe/DMA approach by mid-September.

14:00 → 14:20 Status of "High Priority" BIPXL JIRA Issues

https://its.cern.ch/jira/projects/BIPXL

14:20 → 15:00 Topical presentation(s) & discussion