Ernest Rutherford (1891-1973) explains the Geiger-Marsden experiment by invoking a nuclear atom model and derives the Rutherford cross section. This suggested that Plum pudding model (of J. J. Thomson) of the atom was incorrect.
Editors. "The Rutherford model or planetary model of the atom formulated". The Literary Encyclopedia. First published 01 May 2009
[http://www.litencyc.com/php/stopics.php?rec=true&UID=6425, accessed 01 August 2015.]