Harvard Divinity School will sharply reduce the number of visiting and adjunct professors on its staff, appointing only those “absolutely necessary to cover gaps in the curriculum,” the school announced Wednesday in a letter detailing the school’s response to severe losses in its approximately $620 million endowment. Dean William Graham said the measures will help the school reduce its budget by an additional 4 to 8 percent for the coming fiscal year. Graham also said that the school intends to maintain financial aid at its current levels, though the school will postpone plans to fully fund tuition and fees for all students with need.