The W-Z-Top Bags

TL;DR

This paper explores a new family of multi-quanta bound states in the Standard Model, called W-Z-Top bags, which involve Higgs-mediated attraction among heavy SM particles, with potential cosmological implications.

Contribution

It introduces a self-consistent mean-field approach to identify conditions for the existence of Higgs-depleted bags involving W, Z, and top quarks, including their dependence on Higgs mass.

Findings

Bound states appear at N~10 for light Higgs (~50 GeV).

Metastable W,Z bags form at N~1000 for realistic Higgs (~100 GeV).

Pure top bags do not exist at high N, but top quarks can bind to W-bags.

Abstract

We discuss a new family of multi-quanta bound states in the Standard Model, which exist due to the mutual Higgs-based attraction of the heaviest members of the SM, namely, gauge quanta $W,Z$ and (anti)top quarks, $\bar t, t $. We use a self-consistent mean-field approximation, up to a rather large particle number $N$. In this paper we do not focus on weakly-bound, non-relativistic bound states, but rather on "bags" in which the Higgs VEV is significantly modified/depleted. The minimal number $N$ above which such states appear strongly depends on the ratio of the Higgs mass to the masses of $W,Z,\bar{t}, t $: For a light Higgs mass $m_H \sim 50\, GeV$ bound states start from $N\sim O(10)$, but for a "realistic" Higgs mass, $m_H\sim 100\, GeV$, one finds metastable/bound $W,Z$ bags only for $N\sim O(1000)$. We also found that in the latter case pure top bags disappear for all N, although top quarks can still be well bound to the W-bags. Anticipating cosmological applications (discussed in a companion paper) of these bags as "doorway states" for baryosynthesis, we also consider the existence of such metastable bags at finite temperatures, when SM parameters such as Higgs, gauge and top masses are significantly modified.