Restore strict flux-scale QA on 2026-01-25 hour 22

[jakobtfaber]

Question

Why does the 2026-01-25T2200 hourly-epoch mosaic fail strict flux-scale QA at median ratio 0.688 after same-date BP generation and epoch-gaincal LOW_SNR fallback to the static daily G table, and what minimal correction makes the same checkpoint pass 0.8–1.2 without threshold changes or --lenient-qa?

Acceptance: rerun the same 11-MS hour with strict QA; flux scale, completeness, and noise gates all pass; photometry runs; the public dashboard shows the QA verdict, mosaic/diagnostic previews, and light-curve data. Preserve the measured 12.658 Jy peak and compare the same checkpoint before/after.

Evidence: /data/dsa110-proc/products/mosaics/2026-01-25/run_2026-07-21T02_39_45Z.log, 2026-01-25_run_summary.json, and /stage/dsa110-contimg/images/mosaic_2026-01-25/2026-01-25T2200_mosaic_qa_diag.png. Related calibration finding: #104. Blocks #151.

Part of #144

[jakobtfaber]

Current live evidence from the 2026-01-25T0000 rolling run sharpens this ticket's root-cause path:

• VLASS lookup still failed for Dec +16.1 and selected the geometric centre tile with a source count of -1.
• The reused epoch-gaincal scratch MS was incomplete (table.f3 missing), so epoch gaincal failed immediately and fell back to the static daily G table.
• Three-gate epoch QA then produced ratio=nan; the current NVSS default still points into the archived dsa110-contimg tree.
• The mosaic/weight pair was structurally valid but strict QA failed and archival was blocked.

Canonicalize NVSS and VLASS catalog ownership and lookup now blocks this ticket. After catalog resolution is corrected, this ticket should fix the scratch-MS lifecycle and rerun the same checkpoint with unchanged strict thresholds. Make rolling campaign completion and pruning strict-QA transactional is downstream so another QA-FAIL product cannot be marked complete or pruned.

Evidence: /data/dsa110-proc/products/mosaics/2026-01-25/run_2026-07-21T20_15_58Z.log and the corresponding run report/manifest.

[jakobtfaber]

The active dsa110-contimg catalog dependency that produced missing VLASS/NVSS measurements is removed, canonical full catalogs are validated, and the strict campaign has been restarted immediately with no timer. It is processing oldest-first, so this ticket remains open until the same hour-22 checkpoint reaches all three strict gates.