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Why are electrons present in fusion plasma if nuclei undergo the fusion reactions?

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laser-activated fusion — nuclear fusion Interior of the U.S. Department of Energy's National Ignition Facility (NIF), located at Lawrence Livermore National Laboratory, Livermore, California. The NIF target chamber uses a high-energy laser to heat fusion fuel to temperatures sufficient for thermonuclear ignition. The facility is used for basic science, fusion energy research, and nuclear weapons testing.

In the context of nuclear fusion, electrons are present in the plasma because the fuel must be heated to extreme temperatures—often exceeding 50,000,000 K—to overcome the Coulomb force that causes positively charged nuclei to repel one another.12

When an ordinary gas is heated to these temperatures, the collisions between atoms become so vigorous that electrons are stripped away from their parent atoms. This process creates an ionized gas known as plasma, which consists of a mixture of free negative electrons and positive nuclei.31

While the actual fusion reactions occur exclusively between the nuclei, the electrons remain present in the plasma to maintain macroscopic charge neutrality. Because a plasma is an electrically conducting medium, these free electrons are essential to the state's behavior, allowing it to respond to electromagnetic fields used for confinement and heating in experimental reactors.134