Gamma Arigulon system
The Gamma Arigulon system was a star system that was located in a sector of the Beta Quadrant. It was a single star system consisting of the primary Gamma Arigulon.
The starship LaSalle reported radiation anomalies in the star system in 2367. The USS Enterprise-D was dispatched to investigate but initially detected no irregularities in the primary's radiant energy. As the Enterprise prepared to launch two Class-1 probes to further investigate the star, a Klingon Vor'cha-class attack cruiser carrying Ambassador K'Ehleyr decloaked on an urgent mission, canceling further investigation of the radiation anomalies. (TNG: "Reunion")
In the Bayer designation, which was a system of stellar classification, the Greek letter indicated the brightness of a star in a constellation. In this case, Gamma Arigulon would be the 3rd brightest star in its constellation.
The quadrant of origin for this star system was based on a line of dialog from the episode, where Data said, If true, it would represent a fundamental shift of power in the quadrant. in response to a question from William Riker about a possible alliance between the Klingons and the Romulans. Both species were based in the Beta Quadrant.