Most of her large-scale works reflect her Armenian heritage. On Saturday at 8 p.m., Ms. Ekizian's new work, ''Cantata No. 1: A Saint Gregory Moment,'' will have its world premiere at a free performance by the Brooklyn Philharmonic at the Cathedral of St. John the Divine in Manhattan. Ms. Ekizian said the concert, sponsored by the Interfaith Committee of Remembrance, was dedicated to ''victims of the Holocaust, the Armenian genocide and the World Trade Center disaster.'' Yaakov Bergman of Scarsdale will conduct the orchestra in a program that also includes excerpts of Handel's ''Messiah.'' Marian Najarian of Bronxville, a mezzo-soprano, is a featured artist. Information: (914) 629-6060. Photo Try unlimited access to NYTimes.com for just 99¢. SEE OPTIONS »