Mass-to-charge ratio refers to the molecular or atomic mass number and "z" to the charge number of the ion; however, the quantity of "m"/"z" is dimensionless by definition. An ion of 100 atomic mass units ("m" = 100) carrying two charges ("z" = 2) will be observed at "m"/"z" = 50. In the 19th century, the mass-to-charge ratios of some ions were measured by electrochemical methods. In 1897, the mass-to-charge ratio of the electron was first measured by J. J. Thomson. By doing this, he showed that the electron was in fact a particle with a mass and a charge, and that
Jet (particle physics) Jet (particle physics) A jet is a narrow cone of hadrons and other particles produced by the hadronization of a quark or gluon in a particle physics or heavy ion experiment. Particles carrying a color charge, such as quarks, cannot exist in free form because of QCD confinement which only allows for colorless states. When an object containing color charge fragments, each fragment carries away some of the color charge. In order to obey confinement, these fragments create other colored objects around them to form colorless objects. The ensemble of these objects is called a jet, since the fragments all