[dosh]

This is exciting. Not sure how they will go from electron-positron creation to protons which needs quarks, but according to https://en.wikipedia.org/wiki/Matter_creation

Summary: Matter creation is the conversion of massless particles into one or more massive particles. Since all known massless particles are bosons and the most familiar massive particles are fermions, usually what is considered is the process which converts two bosons (e.g. photons) into two fermions (e.g., an electron–positron pair). This process is known as pair production.

So technically, it is a matter creation.

[KenoFischer]

In theory all you have to do to get protons is crank up the energy.