# Doubly heavy $QQ$ tetraquarks

## TL;DR

This paper explores theoretical models for doubly heavy tetraquarks, ${
m T}_{QQ}$, analyzing their masses and properties, including a soliton-based approach with a distinct large $N_c$ limit, contributing to understanding these exotic states.

## Contribution

It introduces a novel soliton-based model for ${
m T}_{QQ}$ tetraquarks and compares its large $N_c$ behavior with other approaches.

## Key findings

- Model estimates suggest possible bound states of ${
m T}_{QQ}$
- The soliton approach exhibits a different large $N_c$ limit
- Mass predictions vary across models

## Abstract

With the discovery of a doubly charmed $\Xi_{cc}$ baryon a somewhat forgotten issue of tetraquarks containing two heavy and two light (anti) quarks, ${\cal T}_{QQ}$, triggered theorist's interest. We discuss quark model estimates of ${\cal T}_{QQ}$ masses and such objects including a model where the light sector is treated as a soliton. We show that this model has different large $N_c$ limit than other approaches.