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The classical example of a continuous spectrum, from which the name is derived, is the part of the spectrum of the light emitted by excited atoms of hydrogen that is due to free electrons becoming bound to a hydrogen ion and emitting photons, which are smoothly spread over a wide range of wavelengths, in contrast to the discrete lines due to ...
In frequency (and thus energy), UV rays sit between the violet end of the visible spectrum and the X-ray range. The UV wavelength spectrum ranges from 399 nm to 10 nm and is divided into 3 sections: UVA, UVB, and UVC. UV is the lowest energy range energetic enough to ionize atoms, separating electrons from them, and thus causing chemical reactions.
Since the energy levels of electrons in atoms are discrete, each element and each molecule emits and absorbs its own characteristic frequencies. Immediate photon emission is called fluorescence, a type of photoluminescence. An example is visible light emitted from fluorescent paints, in response to ultraviolet . Many other fluorescent emissions ...
The analog of the 4D light field for sound is the sound field or wave field, as in wave field synthesis, and the corresponding parametrization is the Kirchhoff–Helmholtz integral, which states that, in the absence of obstacles, a sound field over time is given by the pressure on a plane. Thus this is two dimensions of information at any point ...
In signal processing, the power spectrum () of a continuous time signal describes the distribution of power into frequency components composing that signal. [1] According to Fourier analysis, any physical signal can be decomposed into a number of discrete frequencies, or a spectrum of frequencies over a continuous range.
A frequency comb or spectral comb is a spectrum made of discrete and regularly spaced spectral lines.In optics, a frequency comb can be generated by certain laser sources.. A number of mechanisms exist for obtaining an optical frequency comb, including periodic modulation (in amplitude and/or phase) of a continuous-wave laser, four-wave mixing in nonlinear media, or stabilization of the pulse ...
X-ray emission spectroscopy (XES) is a form of X-ray spectroscopy in which a core electron is excited by an incident X-ray photon and then this excited state decays by emitting an X-ray photon to fill the core hole. The energy of the emitted photon is the energy difference between the involved electronic levels.
A photon with energy of 60 keV or less has a wavelength of 21 pm or more, so the X-ray spectrum has exactly that cutoff, as seen in the graph. This cutoff applies to both the continuous (bremsstrahlung) spectrum and the characteristic sharp peaks: There is no X-ray of any kind beyond the cutoff. However, the cutoff is most obvious for the ...