The stability of a nucleus or an atom depends on various factors, including the balance between the attractive and repulsive forces among its constituents. In the case of the Δ- particle, which consists of three down quarks, its stability within a nucleus or an atom depends on its ability to form a bound state with other particles and the overall energy of the system.
The Δ- particle has a spin of 2/3 and a mass of approximately 1.32 GeV. It also has a relatively short lifespan on the order of 10^(-23) seconds. These properties suggest that the Δ- particle is not a stable particle in isolation and will decay into other particles relatively quickly.
When considering the stability of a nucleus or an atom, it is important to account for the balance between the strong nuclear force, electromagnetic force, and other interactions. Given that the Δ- particle is positively charged, it would experience repulsive electromagnetic forces within a nucleus or an atom, which could destabilize the system.
If we consider a hypothetical nucleus such as Δ-p, where Δ- is bound to a proton, it would likely face significant electromagnetic repulsion due to the positive charge of the Δ- particle. This repulsion would make the nucleus less stable.
Similarly, if we consider an atom like Δ-ppe-, where Δ- is bound to a proton and two electrons, the positive charge of the Δ- particle would lead to strong electromagnetic repulsion between the Δ- and the protons and electrons. This would likely make the atom less stable.
The same reasoning applies to the hypothetical atom Δ-ppne-, where Δ- is bound to two protons, two neutrons, and an electron. The positive charge of the Δ- particle would again cause repulsion between the Δ- and the protons and electrons, making the atom less stable.
In summary, due to the positive charge and relatively short lifespan of the Δ- particle, it is unlikely that a nucleus or an atom containing a Δ- particle would be more stable. The electromagnetic repulsion between the Δ- and other charged particles would likely destabilize the system.