Short answers, pulled from the story.
The Rutherford scattering experiments took place in the year 1909. Hans Geiger and Ernest Marsden conducted the initial observations under the direction of Ernest Rutherford at the University of Manchester.
Hans Geiger and Ernest Marsden conducted the Rutherford scattering experiments while working under the direction of Ernest Rutherford. Geiger was a German physicist who had visited Rutherford in 1906, and Marsden was an undergraduate student at the time.
The result of the Rutherford scattering experiments showed that a tiny fraction of alpha particles fired at a sheet of gold bounced back toward their source. This observation proved that the positive charge of the atom was concentrated in a tiny, dense core called the nucleus rather than being distributed evenly.
Ernest Rutherford published the paper titled The Scattering of Alpha and Beta Particles by Matter and the Structure of the Atom in the year 1911. This paper introduced a mathematical framework that explained the experimental results through the laws of classical mechanics.
The 1913 Rutherford scattering experiments verified that the number of alpha particles deflected by a given angle was proportional to the cosecant of the angle to the fourth power. These experiments also confirmed that the number of scintillations was proportional to the thickness of the foil and the square of the nuclear charge.
The Rutherford scattering experiments changed the understanding of the atom by proving that positive charge and most of the mass were concentrated in a tiny core at the center of the atom. This discovery moved physics from the plum pudding model to a model of a concentrated nucleus surrounded by empty space.