Search for a new scalar resonance decaying to a Higgs boson and another new scalar particle in the final state with two bottom quarks and two photons in proton-proton collisions at $\sqrt{s}$ = 13 TeV

TL;DR

This paper reports a search for a new scalar resonance decaying into a Higgs boson and another scalar, using proton-proton collision data at 13 TeV, setting upper limits and observing a modest deviation at specific masses.

Contribution

It introduces a novel search for a scalar resonance decaying to a Higgs and another scalar in the bb and gamma gamma final state, with new limits and a potential signal.

Findings

No significant excess overall, compatible with the standard model.

Upper limits on production cross section range from 0.05 to 2.69 fb.

A local significance of 3.33 sigma observed at specific masses.

Abstract

A search is presented for a new scalar resonance, X, decaying to a standard model Higgs boson and another new scalar particle, Y, in the final state where the Higgs boson decays to a $\mathrm{b\bar{b}}$ pair, while the Y particle decays to a pair of photons. The search is performed in the mass range 240$-$1000 GeV for the resonance X, and in the mass range 70$-$800 GeV for the particle Y, using proton-proton collision data collected by the CMS experiment at $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 132 fb$^{-1}$. In general, the data are found to be compatible with the standard model expectation. Observed (expected) upper limits at 95% confidence level on the product of the production cross section and the relevant branching fraction are extracted for the X $\to$ YH process, and are found to be within the range of 0.05$-$2.69 (0.08$-$1.94) fb, depending on $m_\mathrm{X}$ and $m_\mathrm{Y}$. The most significant deviation from the background-only hypothesis is observed for X and Y masses of 300 and 77 GeV, respectively, with a local (global) significance of 3.33 (0.65) standard deviations.