An authority on Blue Note Records, Michael Cuscuna will introduce a screening at the Brattle Theatre of “Blue Note: A Story of Modern Jazz,” of Julian Benedikt’s 1997 documentary about the pioneering jazz record label founded over 70 years ago. This event is part of “Blue Note Records, Then and Now,” a week-long celebration presented by the Office for the Arts’ Jazz Program and Harvard Jazz Bands. Michael Cuscuna is a jazz record producer and writer. He is a leading discographer of Blue Note Records.