Electron capture (sometimes called inverse beta decay) is a decay mode for isotopes that will occur when there are too many protons in the nucleus of an atom and insufficient energy to emit a positron; however, it continues to be a viable decay mode for radioactive isotopes that can decay by positron emission. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides The proton ( Greek πρῶτον / proton "first" is a Subatomic particle with an Electric charge of one positive The nucleus of an Atom is the very dense region consisting of Nucleons ( Protons and Neutrons, at the center of an atom History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny The positrons or antielectron is the Antiparticle or the Antimatter counterpart of the Electron. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. Positron emission is a type of Beta decay, sometimes referred to as " beta plus " (&beta+ If the energy difference between the parent atom and the daughter atom is less than 1. 022 MeV, positron emission is forbidden and electron capture is the sole decay mode. For example, Rubidium-83 will decay to Krypton-83 solely by electron capture (the energy difference is about 0. Rubidium (ruːˈbɪdiəm /rəˈbɪdiəm/ is a Chemical element with the symbol Rb and Atomic number 37 Krypton (ˈkrɪptən or /ˈkrɪptɒn/ from kryptos "hidden" is a Chemical element with the symbol Kr and Atomic number 36 9 MeV).

In this case, one of the orbital electrons, usually from the K or L electron shell (K-electron capture, also K-capture, or L-electron capture, L-capture), is captured by a proton in the nucleus, forming a neutron and a neutrino. The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J An electron shell may be crudely thought of as an Orbit followed by Electrons around an Atom nucleus. This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. Neutrinos are Elementary particles that travel close to the Speed of light, lack an Electric charge, are able to pass through ordinary matter almost Since the proton is changed to a neutron, the number of neutrons increases by 1, the number of protons decreases by 1, and the atomic mass number remains unchanged. The atomic mass (ma is the Mass of an atom most often expressed in unified atomic mass units The atomic mass may be considered to be the total mass By changing the number of protons, electron capture transforms the nuclide into a new element. A nuclide (from lat nucleus is a species of Atom characterized by the constitution of its nucleus and hence by the number of Protons, the number of A chemical element is a type of Atom that is distinguished by its Atomic number; that is by the number of Protons in its nucleus. The atom moves into an excited state with the inner shell missing an electron. Excitation is an elevation in energy level above an arbitrary baseline energy state When transiting to the ground state, the atom will emit an X-ray photon (a type of electromagnetic radiation) and/or Auger electrons. X-radiation (composed of X-rays) is a form of Electromagnetic radiation. Electromagnetic radiation takes the form of self-propagating Waves in a Vacuum or in Matter. The Auger effect (ˈɔːʒɚ or Oh' jeh is a phenomenon in Physics in which the emission of an Electron from an Atom causes the emission of a second

### Reaction Details

 p+ + e- → n0 + νe Examples: $\color{blue}{}^{26}_{13}\,$ Al + e- → $\color{blue}{}^{26}_{12}\,$ Mg + νe $\color{blue}{}^{59}_{28}\,$ Ni + e- → $\color{blue}{}^{59}_{27}\,$ Co + νe $\color{blue}{}^{40}_{19}\,$ K + e- → $\color{blue}{}^{40}_{18}\,$ Ar + νe

Chemical bonds can also affect the rate of electron capture to a small degree (generally less than 1%) depending on the proximity of electrons to the nucleus. A chemical bond is the physical process responsible for the attractive interactions between Atoms and Molecules and which confers stability to diatomic and polyatomic [1]

Around the elements in the middle of the periodic table, isotopes that are lighter than stable isotopes of the same element tend to decay through electron capture, while isotopes heavier than the stable ones decay by electron emission. The periodic table of the chemical elements is a tabular method of displaying the Chemical elements Although precursors to this table exist its invention is In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted A good example of this is silver. Naturally occurring Silver ( Ag) is composed of the two stable Isotopes 107Ag and 109Ag with 107Ag being the more abundant

### Common Examples

Some common radioisotopes that decay by electron capture include:

Be-753. 28 d
Ar-3735. 0 d
Ca-411. 03E5 a
Ti-4452 a
V-49337 d
Cr-5127. 7 d
Mn-533. 7E6 a
Co-57271. 8 d
Ni-566. 10 d
Ga-673. 260 d
Ge-68270. 8 d
Se-728. 5 d

For a full list, see the table of nuclides. A table of nuclides or chart of nuclides is a graphic in which Nuclides are drawn such that one axis represents the number of Neutrons and the

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