nuclear and particle physics an introduction pdf converter

The Rutherford model worked quite well until studies of were carried out by at the in 1929. This was a particularly remarkable development since at that time fusion and thermonuclear energy, and even that stars are largely composed of (see ), had not yet been discovered. At that time, the source of stellar energy was a complete mystery Eddington correctly speculated that the source was of hydrogen into helium, liberating enormous energy according to Einstein's equation E = mc 2. Around 1920, anticipated the discovery and mechanism of processes in, in his paper The Internal Constitution of the Stars. As an example, in this model (which is not the modern one) nitrogen-14 consisted of a nucleus with 14 protons and 7 electrons (21 total particles) and the nucleus was surrounded by 7 more orbiting electrons. The discovery, with Rutherford's analysis of the data in 1911, led to the Rutherford model of the atom, in which the atom had a very small, very dense nucleus containing most of its mass, and consisting of heavy positively charged particles with embedded electrons in order to balance out the charge (since the neutron was unknown). He likened it to firing a bullet at tissue paper and having it bounce off.

But Rutherford instructed his team to look for something that shocked him to observe: a few particles were scattered through large angles, even completely backwards in some cases. The had predicted that the alpha particles should come out of the foil with their trajectories being at most slightly bent. The key experiment behind this announcement was performed in 1910 at the: Ernest Rutherford's team performed a remarkable in which Geiger and Marsden under Rutherford's supervision fired alpha particles ( nuclei) at a thin film of foil.

In 1911–1912 Rutherford went before the Royal Society to explain the experiments and propound the new theory of the atomic nucleus as we now understand it.

More work was published in 1909 by Geiger and, and further greatly expanded work was published in 1910 by Geiger. Expanded on this work in a communication to the with experiments he and Rutherford had done, passing alpha particles through air, aluminum foil and gold leaf.

Nuclear and particle physics an introduction pdf converter