Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles (radiation). Decay is said to occur in the parent nucleus and produces a daughter nucleus. This is a random process, i.e. it is impossible to predict the decay of individual atoms. The SI unit for measuring radioactive decay is the becquerel (Bq). If a quantity of radioactive material produces one decay event per second, it has an activity of one Bq. Since any reasonably-sized sample of radioactive ...

Including:

• Radioactive decay - General introduction
• Radioactive decay - Discovery
• Radioactive decay - Modes of decay
• Radioactive decay - Decay chains and multiple modes
• Radioactive decay - Occurrence and applications
• Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia - Radioactive decay

See also:

Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Modes of decay

As discussed above, the decay of an unstable nucleus (radionuclide) is entirely random and it is impossible to predict when a particular atom will decay. However, it is equally likely to decay at any time. Therefore, given a sample of a particular radioisotope, the number of decay events –dN expected to occur in a small interval of time dt is proportional to the number of atoms present. If N is the number of atoms, then the probability of decay (– dN/N) is proportional to dt: Rearranging, we obtain the following first ...

See also:

Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Decay timing

Alpha particles or alpha rays (named after the first letter in the greek alphabet, α) are a highly ionizing form of particle radiation which have low penetration. They consist of two protons and two neutrons bound together into a particle identical to a helium nucleus; hence, it can be written as He2+. Alpha particles are emitted by radioactive nuclei such as uranium or radium in a process known as alpha decay. This sometimes leaves the nucleus in an excited state, with the emission of a gamma ray removing the excess energy. In contrast to beta decay, ...

Read more here: » Alpha particle: Encyclopedia - Alpha particle

In nuclear physics, a decay product, also known as a daughter product, daughter isotope or daughter nuclide, is a nuclide resulting from the radioactive decay of a parent isotope or precursor nuclide. The daughter product may be stable or it may decay to form a daughter product of its own. The daughter of a daughter product is sometimes called a granddaughter product. Decay products are extremely important in understanding radioa ...

Read more here: » Decay product: Encyclopedia - Decay product

Nucleosynthesis Neutron Capture The R-process The S-process Proton capture: The P-process In nuclear physics, beta decay is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. In the case of electron emission, it is referred to as "beta minus" (β−), while in the case of a positron emission as "beta plus" (β+). In β− decay, the weak interaction converts a neutron ...

Read more here: » Beta decay: Encyclopedia - Beta decay

Beta particles are high-energy electrons or positrons emitted by certain types of radioactive nuclei such as potassium-40. The beta particles emitted are a form of ionizing radiation also known as beta rays. The production of beta particles is termed beta decay. They are designated by the Greek letter beta (β). There are two forms of beta decay, β− and β+, which respectively give rise to the electron and the positron. Beta particle - β− decay electron. Unstabl ...

Including:

• Beta particle - β− decay electron
• Beta particle - β+ decay positron
• Beta particle - The neutrino and conservation of energy

Read more here: » Beta particle: Encyclopedia - Beta particle

Radiation can refer to one of the following: Specific types in physics: Alpha radiation, composed of the nuclei of helium-4 atoms. Beta radiation, consisting of energetic electrons or positrons. Gamma radiation, which are high-energy electromagnetic waves such as X rays. Delta radiation Epsilon radiation Cherenkov radiation, radiation by a particle moving through an insulating medium faster than the speed of light in that medium. Electromagnetic radiation, a str ...

Read more here: » Radiation: Encyclopedia - Radiation

The becquerel (symbol Bq) is the SI derived unit of radioactivity, defined as the activity of a quantity of radioactive material in which one nucleus decays per second. It is therefore equivalent to s-1. The older unit of radioactivity was the curie (Ci), defined as 3.7×1010 becquerels or 37 GBq. In a fixed mass of radioactive material, the number of becquerels changes with time. In some circumstances, amounts of radioactive material are given after adjustment for some period of time. For example, ...

Including:

• Becquerel - Definition
• Becquerel - SI multiples
• Becquerel - Origin

Read more here: » Becquerel: Encyclopedia - Becquerel

Nucleosynthesis Neutron Capture The R-process The S-process Proton capture: The P-process Alpha decay is a form of radioactive decay in which an atomic nucleus ejects an alpha particle and transforms into a nucleus with mass number 4 less and atomic number 2 less. For example: although this is usually written as: Note that an alpha particle is a helium nucleus, and that both mass number and ato ...

Read more here: » Alpha decay: Encyclopedia - Alpha decay

Nucleosynthesis Neutron Capture The R-process The S-process Proton capture: The P-process Cluster decay is the nuclear process in which a radioactive atom emits a cluster of neutrons and protons. While this term technically includes alpha decay, they are usually kept separate because the latter is much more common. Cluster decay only occurs a small percentage of the time in all cases. It also is limited to the heavy atoms which have the energy to ex ...

Read more here: » Cluster decay: Encyclopedia - Cluster decay

Artificial disintegration is the term coined by Ernest Rutherford for the process by which an atomic nucleus is broken down by bombarding it with high speed alpha particles, either from a particle accelerator, or a naturally decaying radioactive substance such as radium, as Rutherford originally used. See also. The Fly in the Cathedral ...

Read more here: » Artificial disintegration: Encyclopedia - Artificial disintegration

The nucleus of an atom is the very dense region in its center consisting of protons and neutrons. The size of the nucleus is much smaller than the size of the atom itself, and almost all of the mass in an atom is made up from the protons and neutrons with almost no contribution from the electrons. Atomic nucleus - Nuclear Makeup. The nucleus of an atom is made up of very tightly bound protons and neutrons. The electromagnetic force which causes like charges to repel prevents protons from binding together wi ...

Including:

• Atomic nucleus - Nuclear Makeup
• Atomic nucleus - Isotopes
• Atomic nucleus - Nuclear Decay
• Atomic nucleus - Nucleus Size
• Atomic nucleus - History
• Atomic nucleus - Nuclear Fusion
• Atomic nucleus - Nuclear Fission
• Atomic nucleus - Production of Heavy Elements
• Atomic nucleus - Nuclear Physics

Read more here: » Atomic nucleus: Encyclopedia - Atomic nucleus

Carbon-14, or 14C, is a radioactive isotope of carbon discovered February 27, 1940, by Martin Kamen and Sam Ruben. Its nucleus contains 6 protons and 8 neutrons. Its presence in organic materials is used in radiocarbon dating. It occurs naturally and has a relative abundance up to 0.00000000012%. The half-life of carbon-14 is 5730 years. It decays into nitrogen-14 through beta-decay. Carbon-14 is produced in the upper layers of the troposphere and the stratosphere ...

Read more here: » Carbon-14: Encyclopedia - Carbon-14

A betalight is an artificial light source powered by the radioactive decay of tritium (H3) gas. The betalight consists of a glass container (usually in the form of a slender tube or two fused glass plates) filled with tritium gas. The inside walls of the enclosure are coated with a phosphor. As the tritium decays, it emits Beta particles (high energy electrons). These electrons stimulate the phosphor, causing it to glow. No external power source is required and the lights are very reliable. This has led to th ...

Read more here: » Betalight: Encyclopedia - Betalight

The weak nuclear force or weak interaction is one of the four fundamental forces of nature. It is most commonly seen in beta decay and the associated radioactivity. The predicate weak derives from the fact that the field strength is some 1013 times less than that of the strong nuclear force. The term nuclear indicates that it is a short-range force, limited to distances smaller than an atomic nucleus. Weak nuclear force - Properties. The weak nuclear force affects all leptons ...

Including:

• Weak nuclear force - Properties
• Weak nuclear force - Decay via the weak force

Read more here: » Weak nuclear force: Encyclopedia - Weak nuclear force

Uraninite is a uranium-rich mineral with a composition that is largely UO2 (uranium oxide), but which also contains UO3 and oxides of lead, thorium, and rare earths. It is most commonly known in the variety pitchblende. All uraninite minerals contain a small amount of radium as a radioactive decay product of uranium; it was in pitchblende from the Jáchymov in Czechoslovakia that Marie Curie discovered radium. Uraninite also always contains small amounts of the lead isotopes, Pb-206 and Pb-207, the end pro ...

Including:

• Uraninite - Reference

Read more here: » Uraninite: Encyclopedia - Uraninite

Background radiation is the ionizing radiation from several natural radiation sources: sources in the Earth and from those sources that are incorporated in our food and water, which are incorporated in our body, and in building materials and other products that incorporate those radioactive sources; radiation sources from space (in the form of cosmic rays); and sources in the atmosphere which primarily come from both the radon gas that is released from the earth's surface and subsequently decays to radioactive atoms that become attach ...

Including:

• Background radiation - Natural background radiation
• Background radiation - Cosmic radiation
• Background radiation - Terrestrial sources
• Background radiation - Radon
• Background radiation - Man-made background radiation
• Background radiation - Man-made radiation sources
• Background radiation - Other usage

Read more here: » Background radiation: Encyclopedia - Background radiation

Radioactivity was first discovered in 1896 by the French scientist Henri Becquerel while working on phosphorescent materials. These materials glow in the dark after exposure to light, and he thought that the glow produced in cathode ray tubes by X-rays might somehow be connected with phosphorescence. So he tried wrapping a photographic plate in black paper and placing various phosphorescent minerals on it. All results were negative until he tried using uranium salts. The result with thes ...

See also:

Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Discovery

Definition and meaning of radioactive decay:

radioactive decay - natural decay of the nucleus of an atom where alpha or beta and/or gamma rays are released at a fixed rate

(Source: US National Oceanic and Atmospheric Administration (NOAA) )

Also see these pages: Oceanography, Oceanography Sitemap, Coral Reef, Environment, Sustainability, Climate Change,