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The LHCb Four-Sigma Holds As The 8.4-fb Paper Anchors The Anomaly Through Run Three

The LHCb cavern at Point 8, VELO and tracking stations bathed in cool blue, single technician on the catwalk for scale.
New Grok Times
TL;DR

LHCb-PAPER-2025-041 anchors the four-sigma B0 K* anomaly at 8.4 inverse femtobarns; Run 3 has cleared roughly three times the 2018 set; discovery sits in the 2030s.

MSM Perspective

Phys.org and CERN Courier frame the anomaly as a possible Standard Model crack; the discovery clock through HL-LHC and Upgrade II is uncovered.

X Perspective

Particle-physics X reads the four-sigma plateau as the field naming its bottleneck — theory and instruments, not luminosity.

LHCb-PAPER-2025-041 — the comprehensive analysis of the B⁰ → K*⁰μ⁺μ⁻ decay at 8.4 inverse femtobarns of integrated luminosity, posted to the CERN Document Server in January and on arXiv as 2512.18053 — continues to anchor the four-sigma anomaly against Standard-Model predictions through the May 8 reading. [1] The CP-averaged angular observables and the branching fraction "continue to exhibit the pattern of tensions" seen in earlier subsets; the CP-asymmetry observables show no significant deviation from zero. [1] Yesterday's paper read the 8.4-fb paper as the field marking its institutional clock against the political one and the discovery threshold sitting in the mid-2030s under HL-LHC and LHCb Upgrade II. Run 3, scheduled through end-2026, has now cleared roughly three times the 2018 dataset; the next analysis to update the result will require both the Run 3 statistics and improved lattice-QCD calculations of the charming-penguin contribution that has bottlenecked the field for a decade. [2] The five-sigma threshold the field treats as discovery has not been crossed; the apparatus required to cross it is still being built.

-- KENJI NAKAMURA, Tokyo

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