# Pseudoscalar pair production via off-shell Higgs in composite Higgs models

### Submission summary

 As Contributors: Diogo Buarque Franzosi · Gabriele Ferretti Arxiv Link: https://arxiv.org/abs/2005.13578v3 (pdf) Date submitted: 2020-09-11 11:59 Submitted by: Buarque Franzosi, Diogo Submitted to: SciPost Physics Discipline: Physics Subject area: High-Energy Physics - Phenomenology Approaches: Theoretical, Experimental, Phenomenological

### Abstract

We propose a new type of search for a pseudoscalar particle $\eta$ pair produced via an off-shell Higgs, $pp\to h^*\to \eta\eta$. The search is motivated by a composite Higgs model in which the $\eta$ is extremely narrow and decays almost exclusively into $Z\gamma$ in the mass range $65$ GeV$\lesssim m_\eta \lesssim 160$ GeV. We devise an analysis strategy to observe the novel $Z\gamma Z\gamma$ channel and estimate potential bounds on the Higgs-$\eta$ coupling. The experimental sensitivity to the signatures depends on the power to identify fake photons and on the ability to predict large photon multiplicities. This search allows us to exclude large values of the compositeness scale $f$, being thus complementary to other typical processes.

###### Current status:
Editor-in-charge assigned

### List of changes

- Last two sentences on 3rd paragraph of introduction about eta-fermion coupling.
- Footnote on 4th paragraph of introduction about eta-photon and eta-gluon coupling.
- Sentence on 4th paragraph of intro to clarify the smallness of fermion decay channel.
- Reference to sec. 4 on paragraph 6 of intro for t-tbar-eta-eta detail.
- Footnote about Delphes object definition and pt of photon on 1st paragraph of sec. 3.
- Sentence about implication of photon pt on 6th paragraph of Sec. 3.1.
- Further discussion about (3.3) just below it.
- A parenthesis in conclusion specifying that the exclusion for large f is also only for small m_eta