Ernest Marsden and Hans Geiger observed alpha particles scattered through large angles by metal targets. Counting weak scintillations supplied an event-based readout even when only a small fraction of the incident beam returned toward its source. The observation challenged descriptions that attributed all deflections to many weak encounters. Their later measurements varied geometry and target conditions to test the single-scattering interpretation behind Rutherford scattering.[ref]
On a Diffuse Reflection of the Alpha-Particles by Hans Geiger and Ernest Marsden. 1909 paper, pp. 495–500, apparatus and reflected-particle counting
A physicist.[ref]
Marsden, Ernest by Ross Galbreath. Dictionary of New Zealand Biography; Independent biographical identity and professional specialization
Portrait of Ernest Marsden
. S. P. Andrew Ltd.; National Library of New Zealand collection, photograph dated 1921. The Commons File records expired-copyright public-domain status in the United States., via Wikimedia Commons. Source. Articles by others on the same topic
Ernest Marsden was a notable British physicist best known for his work in early atomic physics. He was born on March 15, 1889, and is most famously associated with the gold foil experiment conducted with Ernest Rutherford in 1909, which provided significant evidence for the nuclear model of the atom.