Why do alpha particles cause intense ionization over short distances in tissue?

Alpha particles cause intense ionization over short distances in tissue primarily due to their physical properties: they are relatively heavy and carry a double positive charge.12

Because of their significant mass and $2+$ charge, alpha particles interact strongly with the atomic electrons of the medium through which they travel. As they move, they dissipate their kinetic energy by forcing these electrons out of atoms—a process known as ionization—or by promoting them to higher energy levels.32

This high rate of energy loss per unit path length, referred to as linear energy transfer (LET), means that alpha particles deposit a large amount of energy in a very concentrated area. Consequently, they quickly exhaust their energy, resulting in a very short range in tissue. While this limited penetration makes them less hazardous externally, their ability to produce dense, clustered ionizations makes them highly effective at causing biological damage if the source is deposited internally.4235