A Photon is the smallest discrete amount or quantum of electromagnetic radiation. It is the basic unit of light. According to Einstein’s light quantum theory, photons have energy equal to their oscillation frequency times Planck’s constant. Einstein proved that light is a flow of photons, the energy of these photons is the height of their oscillation frequency, and the intensity of the light corresponds to the number of photons. Essentially, the explained how a stream of photons can act both as a wave and particle.
Leptons: fermions that interact weakly and ectromagnetically e, μ, t, veand vt in addition to the respective antriparticles, are leptons. Quarks: fermions that interact strongly to create the hadrons. They are up (u), down (d), strange (s), charm (c), bottom (b) and top (t), and the respective antiquarks. Field Quanta: they are bosons responsible for the fundamental forces. The photons (y) is involved in the electromagnetic field, the gluon in the strong field and the W and Z bosons, with mass, in the weak field. The Higgs boson is an elementary, massive, and scalar boson associated with the Higgs field. It plays a fundamental role in the Standard Model by conferring the mass to the elementary particles.
Wave-particle duality and uncertainty have been fundamental concept in quantum physics since the early 1900s. The uncertainty principle, developed by W.Heisenberg, is a key principle in quantum mechanics. This principle states that it is impossible to know certain pairs of things about a quantum particle at once. For example, very roughly, it states that if we know everything about where a particle is located (the uncertainty of position is small), we know nothing about its momentum (the uncertainty of momentum is large), and vice versa. Versions of the uncertainty principle also exist for other quantities as well, such as energy and time, and in general, it asserts that accurate knowledge of complementarity pairs is impossible except by probabilities. The uncertainty principle is a statement of the effects of wave-particle duality on the properties of subatomic objects.
A semiconductor has conductive properties located in the intermediate zone between a conductor and an insulator. The energy levels are mixed in a complex way and are so close to being considered as continous bands. Semiconductor are usually ‘doped’, i.e, the number of electrons and holes becomes different due to the impurity addiction: electron donors (n-doping) and electron acceptors (p-doping). The semiconductor detectors have excellent spatial resolution and high intrinsic energy resolution. A limit is due to the construction complexity of the big surfaces.
A semiconductor diode is a crystalline piece of semiconductor material with a p-n junction connected to two electrical terminals. The silicon p-n junction was discovered by Russell Ohl in 1940 when observed the photovoltaic effect of light on a silicon rod. This junction can work as a radiation detector.
The photons can interact with matter through three different processes: photoelectric effect, Compton effect and creation of pairs (e+ e). In the Photoelectric interaction, all the photon energy is transferred to the bound atomic electron. It dominates at energies below 100 keV.
γ + atom -> ion + e
If a charged particle passes through a material medium, several phenomena can occur. One is the ionization process that is observable through the production of detectable free charges. This phenomenon increases with the increase of energy. The lines of force of the interacting particle are thickened in the direction orthogonal to the direction, amplyfing the intensity of the field and facilitating the ionization.
The high intensity of the electric field generates, together with the primary avalanche due to ionization, multiple avalanches and photons that can ionize the molecules. The avalanche spreads causing a complete discharge. The collected charge is independent of the primary ionization, so the detection is not proportional to the radiation energy.
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