How does electron capture generate x rays

The electron on the left side of the equation is usually absorbed from the K or L shell of the parent nucleus. Note the reduction in atomic number but conservation of mass number in the daughter nucleus.

The decay pathway has similarities to beta decay and is often termed inverse beta decay 2. The decay energy is almost wholly transferred to the emitted neutrino with a characteristic quanta of energy.

The electron capture decay pathway is usually associated with several other processes. A continuous spectra of Bremsstrahlung is radiated as the inner shell electron is propelled towards the nucleus.

The vacancy left by this electron is then filled by an outer orbital electron setting off a cascade of electron transitions with their associated characteristic x-rays emission.

These transitions may result in the loss of an outer orbital electron, where it is ejected as an Auger electron. Electron capture is rarely an exclusive decay mode and typically occurs alongside beta-plus decay within the radioactive sample. Typically, it occurs in heavy nuclei with a relative abundance of protons or where insufficient decay energy exists for positron emission to occur 3. An isotope making use of electron decay is iodine as a tracer in thyroid imaging 4 which decays by electron capture to tellurium which emits a low energy gamma ray for detection.

The significance of electron capture decay pathway being that no electrons are emitted and therefore reduced risk to adjacent tissue. Experimental confirmation of electron capture was first reported by Luis Alvarez in for Vanadium 5. Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. Updating… Please wait.

Unable to process the form. Check for errors and try again. Who wrote the theory of electron capture? What are Auger electrons? What is L-electron capture?

What is K-electron capture? What causes electron capture? See all questions in Electron Capture. Impact of this question views around the world. You can reuse this answer Creative Commons License. These events would go unnoticed if it were not for the restructuring that the nucleus and electron shells both undergo. Electrons are usually captured from the inner K layer, leaving 'holes' behind them.

Such a capture may also leave the nucleus in an excited state, at a higher energy its ground state, causing it to release desexcitation gamma rays. As a result, electron capture particular decay mode is very hard to detect. This particular decay mode was discovered only in by the American physicist Luis Alvarez , some forty years after the discovery of beta-negative radioactivity and only a few years after the observation of the positron and beta-positive decays.

Luis Alvarez, a physics Nobel laureate, had a long and brilliant career as a physicist. For instance, far away from electron capture, he proposed in a now famous explanation of the dinosaurs extinction, suggesting it had been caused by an asteroid colliding with the Earth some million years ago.

Access to page in french. EN FR. Electron Capture A minor mode The positron observed in the final stage of the beta decay top is a new particle requiring the 0.