Award Session

André Authier

André Authier is a specialist of the dynamical theory of X‐ray diffraction by crystals and X‐ray topography. He was the first to make a direct observation of the propagation of X‐ray wave fields in a crystal at the Bragg reflection and was one of the early contributors to the theory of the diffraction of X‐rays by highly deformed crystals. With co‐worker F. Balibar, he determined the limit above which ray theory is no longer applicable. He analysed and explained the formation of the various parts of the image of the defects in X‐ray topography. He applied X‐ ray topography to the characterization and study of crystal defects, such as growth defects as well in synthetic crystals and in minerals, ferroelectric domains and electrical defects in semiconductors. He has published and edited many books in X-ray diffraction and imaging, including the recent books, “Dynamical Theory of X-Ray Diffraction” and “Early Days of X-Ray Crystallography”.

Yvonne Mascarenhas 

Amongst numerous honorary degrees, prizes and academic positions, in 1998 the Brazilian Government awarded her the National Order of Scientific Merit. In 2000, she became Titular Member of the Brazilian Academy of Sciences. She is also Professor Emeritus of both the ‘Universidade de São Paulo’ and ‘Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq’. The latter is the Brazilian agency in charge of scientific and technological development.