Aaron Stephan’s “Luminous Arbor” sculpture now shines brightly at Woodfords Corner in Portland, the chaotic intersection of Forest Avenue, Woodford Street and Deering Avenue that draws about 27,000 vehicles a day. Stephan envisions the piece as a “graceful anchor” in the form of a tree, each branch punctuated with dimly lit LED streetlights. The sculpture’s installation in front of the historic Odd Fellows Hall and clock tower signals the final stage of the city’s $5 million infrastructure project, which includes realigning traffic lanes, improving a railroad crossing and widening sidewalks.