Ernest Omar Wollan (November 6, 1902 – March 11, 1984) was an American physicist who made major contributions in the fields of neutron scattering and health physics.After earning a bachelor's degree at Concordia College in 1923, he undertook graduate study at the University of Chicago, where he investigated X-ray scattering under Arthur Compton and received a Ph.D. in 1929.After some early setbacks, in December 1944 Wollan and chemist Lyle Benjamin Borst successfully used neutron diffraction to produce "rocking curves" for crystals of gypsum and sodium chloride (salt).[7] In collaboration with Clifford G. Shull, who joined him at ORNL in 1946, he developed neutron diffraction methodology used for determining atomic resolution structure of substances.In his Nobel lecture Shull spoke of Wollan's contributions and expressed regret that his colleague had not lived long enough to share in the prize.
Hand-plotted rocking curves for Bragg scattering from single sodium chloride (salt) crystals at the X-10 reactor at Oak Ridge, obtained by Ernest O. Wollan and Lyle B. Borst in December 1944.