The Arcturian/Sirian Matrix is a concept that is found in the work of Lyssa Royal and Keith Priest. It is the name given to a network of higher dimensional healers.
"The combined energies of Arcturus and Sirius provide a balance of physical, emotional, and spiritual healing. This matrix has been tapped into by humanity since its inception and has been known through many archetypal ideas." (Lyssa Royal & Keith Priest, The Prism of Lyra).
The Arcturians take care of the emotional and spiritual healing; the Sirians of the 'physical' healing.
Lyssa Royal & Keith Priest, The Prism of Lyra.