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Title: Is there a new scalar boson near 95 GeV?
Plain: Searches for extra Higgs-like particles at the LHC, and earlier at the LEP collider, show small excesses of events near 95 GeV, below the known 125 GeV Higgs. Each excess is weak by itself, and it is unknown whether they come from one real particle.
Precise: Run 2 diphoton searches show excesses near $m = 95.4 \mathrm{GeV}$ in CMS ($2.9\sigma$ local) and ATLAS ($1.7\sigma$ local), about $3.1\sigma$ local combined (Biekotter, Heinemeyer, Weiglein, arXiv:2306.03889); CMS also reported a ditau excess of $2.6 \text{ to } 3.1\sigma$ local at 95 to 100 GeV, and LEP a mild bb excess near 98 GeV. Determine whether a scalar S with $m_{S} \sim 95 \mathrm{GeV}$ exists, by a $\ge 5\sigma$ observation in at least one channel or exclusion of the production rates needed to fit the excesses.
Settled by: LHC Run 3 and HL-LHC low-mass diphoton, ditau and bb searches, and a recoil-mass search for $e+ e- \to Z S$ at a Higgs factory.
Kind: well-posed
Answer type: yes-no
References: (empty)
Literature status: open
Status note: Phenomenology papers through mid-2026 still quote a combined diphoton excess near $3\sigma$ local; no Run 3 result confirming or removing it was found in this review (moderate confidence).
Posed since: 2018