Discovery of an unexpectedly light and narrow beauty-strange state - It exhibits a narrow natural width and a substantial mass deficit compared to the conventional quark model predictions. This result marks the first observation of a nonconventional single-beauty hadron.
arxiv.org/abs/2609.25178

Measurement of the Ωb⁻ baryon lifetime - The Ωb⁻ lifetime is 1.751±0.089±0.022 ps, where the uncertainties are statistical and systematic. This measurement improves on the precision of the Ωb⁻ lifetime by about a factor of two over the previous world average. arxiv.org/abs/2609.25370

First measurement of the forward rapidity dependence of W boson transverse helicity fractions - The results show a strong rapidity dependence and agree with NLO SM predictions, providing the first determination of the W transverse helicity fractions in the forward region.

arxiv.org/abs/2609.22555

Observation of the doubly charmed baryon Ωcc⁺ - A peaking structure with a global significance of 8.7σ is observed in the Ωc⁰π⁺mass spectrum at a mass of 3725.9±1.0±0.2±0.4(lifetime)±0.6(ext) MeV
arxiv.org/abs/2609.21921

Observation of Ξb⁰→Ξ⁰J/ψ and evidence for Ξb⁰→Ξ⁰ψ(2S) decays - The Ξ⁰ hyperon is fully reconstructed for the first time at an LHC experiment, which is achieved using the Ξ⁰→Λπ⁰ decay. arxiv.org/abs/2609.15251

Branching fraction measurements of η and η′(958) anomalous decays - This marks the first experimental search for the η′(958)→μ⁺μ⁻ decay, and the most precise measurement of the branching fraction B(η→μ⁺μ⁻) to date. arxiv.org/abs/2609.02973

Stringent limits on CPT- and Lorentz-invariance violation from Bₛ⁰ meson decays - Without assuming Lorentz-invariance violation, the CPT-violating parameter zis measured to be Re(z)=0.018±0.016±0.003 and Im(z)=0.003±0.004±0.002. arxiv.org/abs/2609.02475

First measurement of the ratio of ψ(2S)-to-J/ψ inclusive production in pAr and pp collisions at √s=113GeV with SMOG2 - Data samples were collected during argon and hydrogen gas injections in the SMOG2 storage cell, resulting in pAr and pp collisions, respectively. arxiv.org/abs/2608.30534

Observation of the Ξc⁰→ pK⁻ decay and measurement of its decay asymmetry - Using the decay chain Ξb⁻→Ξc⁰(→ pK⁻)π⁻, the decay asymmetry parameter of the Ξc⁰→ pK⁻ decay is determined to be 0.32±0.15±0.01. arxiv.org/abs/2608.27894

These are hadrons number 84 and 85 observed at the LHC, of which 75 were observed by LHCb. The full list is maintained by @koppenburg.ch, see www.koppenburg.ch/particles.html .