To honor the memory of Roy A. Johnson, a slain UA music professor, "Celebrating the Organ," a three-day conference in tribute to the late professor's legacy, begins tomorrow.

After performing in a concert at a Green Valley church, 59-year-old Johnson disappeared Feb. 28, 1995. His body was found, facedown in a wash just off West Ajo Way and South Sandario Road, four days later.

His killer, Beau John Greene, was sentenced to death in August 1996 and the decision was upheld in October 1998.

"It's the 10th anniversary of my husband's murder. This is to honor his memory and celebrate his life," said Stardust Johnson, dean of the American Guild of Organists' Southern Arizona chapter.

"We'd been married 35 years at the time of his death. He'd been on the faculty for 29," she said.

Tucson Mayor Bob Walkup proclaimed tomorrow to be Celebrating the Organ Day, devoted to Roy Johnson.

In addition to a performance by UA associate music professor Pamela Decker and a lecture by UA professor John Brobeck, two world-class organists were also invited to perform.

"At the time of my husband's death, he had a grant to fund a concert such as this, and he had intended to invite both Tom Murray and Daniel Roth," Johnson said. "So, when we decided to do this conference, I thought that I would invite both of those people because they're two people I know my husband wanted to invite."

Roth, professor of organ at the Musikhochschule in Frankfurt and titular organist at St. Sulpice in Paris, will perform compositions by Felix Mendelssohn-Bartholdy, Johann Sebastian Bach, among others, before ending with a trademark improvisational performance in Holsclaw Hall in the Music building, tomorrow at 8 p.m.

Murray, an organist and music professor at Yale University, will give a talk on composer Felix Mendelssohn-Bartholdy titled "Mendelssohn Discovered" Saturday afternoon and then will perform a recital at Northminster Presbyterian Church, located at 2450 E. Ft. Lowell Road, on Sunday.

"It will be a privilege to have a part in this festival, something I am proud to do," Murray said.

Roy and Stardust Johnson first met Murray when he performed in Tucson in the late 1960s as a young organ competition winner.

"I remember at that time, my husband saying that he'd really go far, which he has," Johnson said.

Though most of professor Johnson's students have since graduated and left Tucson, his widow said, some of his students are still in town and will be in attendance; one is coming all the way from England.

"Losing Roy left an enormous void, not only for me, but in the community at the university and the school of music," Johnson said. "He's been deeply, deeply mourned for such a senseless waste of a beautiful human being."

The Johnsons' son, Eric, who builds organs for Quimby Pipe Organs, will be on Saturday's panel discussion, "21st Century Trends in Organ Design and Construction," at Grace St. Paul's Episcopal Church, located at 2331 E. Adams St.

The Johnsons also have a daughter, Jennifer Johnson-Martinez, who works as an attorney for the state legislature.

Though the three evening concerts, which are open to the public, are not a fundraiser, Stardust Johnson said they hope to make enough money to cover their expenses.

"My husband ... was ... an exceptional human being," she said. "He was kind. He was compassionate. He was witty. He was a scholar, a consummate musician and performer himself. A beautiful human being whose life was cruelly extinguished in a violent act of homicide."

The series of concerts and lectures, jointly sponsored by the School of Music and AGO, takes place tomorrow through Sunday.

Pamela Decker, UA associate professor of organ and music theory, will perform two world premieres, one of which was commissioned and composed in the memory of Roy Johnson. She will perform the work "Children of the Heavenly Father," which is based on the Swedish hymn tune "Tryggare kan ingen vara" Saturday at Grace St. Paul's Episcopal Church.

John T. Brobeck, UA professor and coordinator of musicology, will share insights on the music being performed by Thomas Murray written by Vivaldi, Schumann, Mendelssohn and Elgar in a pre-recital talk at Northminster Presbyterian Church on Sunday at 2:15 p.m.