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Rutherford backscattering (or RBS, for Rutherford Backscattering Spectrometry) is an analytical technique in materials science. It is named for Ernest Rutherford who in 1911 first explained Geiger and Marsden's experimental results for alpha particle scattering from very thin gold foils in a backward direction by using the Coulomb electrostatic force between the positively charged nucleus and the positively charged alpha particle. Rutherford first correctly described the atom as a tiny positive nucleus surrounded by negatively charged electrons (essentially the Bohr atom) on the basis of this experiment. This contradicted J.J. Thomson's "plum pudding model" then current. Rutherford famously expressed his surprise at this experiment: "It was as though one fired a bullet at a piece of paper, and it bounced back at you!" The Materials Science Tetrahedron Materials science is a multidisciplinary field focusing on functional solids, whether the function served is structural, electronic, thermal, chemical, magnetic, optical, or some combination of these. ...
Ernest Rutherford, 1st Baron Rutherford of Nelson, OM, FRS (August 30, 1871 - October 19, 1937), called father of nuclear physics, pioneered the orbital theory of the atom notably in his discovery of rutherford scattering off the nucleus with his gold foil experiment. ...
An alpha particle is deflected by a magnetic field Alpha particles or alpha rays (named after the first letter in the greek alphabet) are a form of particle radiation which are highly ionizing and have low penetration. ...
The gold foil experiment was an experiment done by Ernest Rutherford to determine the layout of the atom. ...
The coulomb, symbol C, is the SI unit of electric charge, and is defined in terms of the ampere: 1 coulomb is the amount of electric charge (quantity of electricity) carried by a current of 1 ampere flowing for 1 second. ...
In physics, the electrostatic force is the force arising between static (that is, non-moving) electric charges. ...
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The Bohr model of the atom The Bohr Model is a physical model that depicts the atom as a small positively charged nucleus with electrons in orbit at different levels, similar in structure to the solar system. ...
Sir Joseph John Thomson, OM, PRS (December 18, 1856 – August 30, 1940) often known as J. J. Thomson, was an English physicist, the discoverer of the electron. ...
A schematic representation of the plum pudding model of the atom. ...
A high energy beam ( 2 to 4 MeV ) of low mass ions ( e.g. He++ ) is directed at a sample. A detector is placed such that particles which scatter from the sample at close to a 180 degree angle will be collected. The energy of these ions will depend on their incident energy and on the mass of the sample atom which they hit, because the amount of energy transferred to the sample atom in the collision depends on the ratio of masses between the ion and the sample atom. Thus, measuring the energy of scattered ions indicates the chemical composition of the sample. A beam of light is a light ray. ...
An ion is an atom or group of atoms with a net electric charge. ...
In general, something that reacts to stimuli in a set manner, and is either part of a living being, or made by a living being, for the purpose of doing such reacting. ...
Additionally, in the case that the incident ion doesn't hit any of the atoms near the surface of the sample, but instead hits an atom deeper in, the incident ion loses energy gradually as it passes through the solid, and again as it leaves the solid. This means that RBS can be used as a means to perform a depth profile of the composition of a sample. This is especially useful in analysis of thin-film materials. For example, films about half a micrometre in thickness can be profiled using a 2 MeV He beam, or films up to about 10 micrometres thick can be profiled with a 2 MeV H beam.
RBS is now a very widely used analytical technique, which has the great advantage that it is absolute, requiring no standards for quantification (since the probability of interaction - the cross-section - is given by the Coulomb potential). It is one of a family of techniques, collectively known as Ion beam analysis. Ion beam analysis is an important family of modern analytical techniques involving the use of MeV ion beams to probe the composition, obtain elemental depth profiles, or determine the depth profile of damage in single crystals. ...
See also Nuclear reaction analysis (NRA) is a nuclear method in materials science to obtain concentration vs. ...
External links - Rutherford Backscattering Spectrometry Theory Tutorial
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