X-ray tube
Spectrum of the X-rays emitted by an X-ray tube with a rhodium target, operated at 60 kV. The connected ambit is due to bremsstrahlung, and the spikes are appropriate K ambit for rhodium. The ambit goes to aught at 21 message in acceding with the Duane–Hunt law, as declared in the text.
Main article: X-ray
In an X-ray tube, electrons are accelerated in a exhaustion by an electric acreage and attempt into a section of metal alleged the "target". X-rays are emitted as the electrons apathetic down (decelerate) in the metal. The achievement spectrum consists of a connected spectrum of X-rays, with added aciculate peaks at assertive energies (see blueprint on right). The connected spectrum is due to bremsstrahlung, while the aciculate peaks are appropriate X-rays associated with the atoms in the target. For this reason, bremsstrahlung in this ambience is aswell alleged connected X-rays.7
The spectrum has a aciculate blow at low wavelength, which is due to the bound activity of the admission electrons. For example, if an electron in the tube is accelerated through 60 kV, again it will access a active activity of 60 keV, and if it strikes the ambition it can actualize X-rays with activity of at a lot of 60 keV, by attention of energy. (This high absolute corresponds to the electron advancing to a stop by abounding just one X-ray photon. Usually the electron emits abounding photons, and anniversary has an activity beneath than 60 keV.) A photon with activity of at a lot of 60 keV has amicableness of at atomic 21 pm, so the connected X-ray spectrum has absolutely that cutoff, as apparent in the graph. More about the blueprint for the low-wavelength blow is:8
\lambda_{\text{min}} = \frac{h c}{e V} \approx \frac{1239.8 \text{ pm}}{V\text{ in kV}} \,
where h is Planck constant, c is the acceleration of light, V is the voltage that the electrons are accelerated through, e is the elementary charge, and message is picometres. This is alleged the Duane–Hunt law.
edit Beta decay
Main article: Beta decay
Beta particle-emitting substances sometimes display a anemic radiation with connected spectrum that is due to bremsstrahlung. In this context, bremsstrahlung is a blazon of "secondary radiation", in that it is produced as a aftereffect of endlessly (or slowing) the primary radiation (beta particles). In electron and positron discharge the photon's activity comes from the electron/nucleon pair, with the spectrum of the bremsstrahlung abbreviating continuously with accretion activity of the beta particle. In electron abduction the activity comes at the amount of the neutrino, and the spectrum is greatest at about one third of the accustomed neutrino energy, extensive aught at aught activity and at accustomed neutrino energy.
edit Inner and alien bremsstrahlung
The "inner" bremsstrahlung arises from the conception of the electron and its accident of activity (due to the able electric acreage in the arena of the basis ability decay) as it leaves the nucleus. This is to be assorted with the "outer" bremsstrahlung due to the approximation on the basis of electrons advancing from the alfresco (i.e., emitted by addition nucleus).9
edit Radiation safety
In some cases, e.g. 32P, the bremsstrahlung produced by careful the beta radiation with the commonly acclimated close abstracts (e.g. lead) is itself dangerous; in such cases, careful have to be able with low body materials, e.g. Plexiglass (lucite), plastic, wood, or water;10 because the amount of deceleration of the electron is slower, the radiation accustomed off has a best amicableness and is accordingly beneath penetrating.
Spectrum of the X-rays emitted by an X-ray tube with a rhodium target, operated at 60 kV. The connected ambit is due to bremsstrahlung, and the spikes are appropriate K ambit for rhodium. The ambit goes to aught at 21 message in acceding with the Duane–Hunt law, as declared in the text.
Main article: X-ray
In an X-ray tube, electrons are accelerated in a exhaustion by an electric acreage and attempt into a section of metal alleged the "target". X-rays are emitted as the electrons apathetic down (decelerate) in the metal. The achievement spectrum consists of a connected spectrum of X-rays, with added aciculate peaks at assertive energies (see blueprint on right). The connected spectrum is due to bremsstrahlung, while the aciculate peaks are appropriate X-rays associated with the atoms in the target. For this reason, bremsstrahlung in this ambience is aswell alleged connected X-rays.7
The spectrum has a aciculate blow at low wavelength, which is due to the bound activity of the admission electrons. For example, if an electron in the tube is accelerated through 60 kV, again it will access a active activity of 60 keV, and if it strikes the ambition it can actualize X-rays with activity of at a lot of 60 keV, by attention of energy. (This high absolute corresponds to the electron advancing to a stop by abounding just one X-ray photon. Usually the electron emits abounding photons, and anniversary has an activity beneath than 60 keV.) A photon with activity of at a lot of 60 keV has amicableness of at atomic 21 pm, so the connected X-ray spectrum has absolutely that cutoff, as apparent in the graph. More about the blueprint for the low-wavelength blow is:8
\lambda_{\text{min}} = \frac{h c}{e V} \approx \frac{1239.8 \text{ pm}}{V\text{ in kV}} \,
where h is Planck constant, c is the acceleration of light, V is the voltage that the electrons are accelerated through, e is the elementary charge, and message is picometres. This is alleged the Duane–Hunt law.
edit Beta decay
Main article: Beta decay
Beta particle-emitting substances sometimes display a anemic radiation with connected spectrum that is due to bremsstrahlung. In this context, bremsstrahlung is a blazon of "secondary radiation", in that it is produced as a aftereffect of endlessly (or slowing) the primary radiation (beta particles). In electron and positron discharge the photon's activity comes from the electron/nucleon pair, with the spectrum of the bremsstrahlung abbreviating continuously with accretion activity of the beta particle. In electron abduction the activity comes at the amount of the neutrino, and the spectrum is greatest at about one third of the accustomed neutrino energy, extensive aught at aught activity and at accustomed neutrino energy.
edit Inner and alien bremsstrahlung
The "inner" bremsstrahlung arises from the conception of the electron and its accident of activity (due to the able electric acreage in the arena of the basis ability decay) as it leaves the nucleus. This is to be assorted with the "outer" bremsstrahlung due to the approximation on the basis of electrons advancing from the alfresco (i.e., emitted by addition nucleus).9
edit Radiation safety
In some cases, e.g. 32P, the bremsstrahlung produced by careful the beta radiation with the commonly acclimated close abstracts (e.g. lead) is itself dangerous; in such cases, careful have to be able with low body materials, e.g. Plexiglass (lucite), plastic, wood, or water;10 because the amount of deceleration of the electron is slower, the radiation accustomed off has a best amicableness and is accordingly beneath penetrating.
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