Nuclear physics

The energy released from a nuclear weapon detonated in the troposphere can be divided into four basic categories: * Blast—40–50% of total energy * Thermal radiation—30–50% of total energy * Ionizing radiation—5% of total energy (more in a neutron bomb) * Residual radiation—5–10% of total energy with the mass of the explosion When an air burst occurs, lethal blast and thermal effects proportionally scale much more rapidly than lethal radiation effects, as higher and higher yield nuclear weapons are used.

In nuclear physics and particle physics, isospin (isotopic spin, isobaric spin) is a quantum number related to the strong interaction.

A nuclear explosion is an explosion that occurs as a result of the rapid release of energy from a high-speed nuclear reaction.

In quantum mechanics, a parity transformation (also called parity inversion) is the flip in the sign of one spatial coordinate.

Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or 'decays' into an atom with a mass number that is reduced by four and an atomic number that is reduced by two.

(See also: List of elements by atomic number) In chemistry and physics, the atomic number of a chemical element (also known as its proton number) is the number of protons found in the nucleus of an atom of that element, and therefore identical to the charge number of the nucleus.

The nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment.

In particle physics, the baryon number is a strictly conserved additive quantum number of a system.

A beta particle, sometimes called beta ray, denoted by the lower-case Greek letter beta (β), is a high-energy, high-speed electron or positron emitted in the radioactive decay of an atomic nucleus, such as a potassium-40 nucleus, in the process of beta decay.

In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which a beta ray, and a respective neutrino are emitted from an atomic nucleus.

In particle physics, a fermion (a name coined by Paul Dirac from the surname of Enrico Fermi) is any particle characterized by Fermi–Dirac statistics.

Half-life (abbreviated t1⁄2) is the time required for a quantity to reduce to half its initial value.

The heat of combustion is the total energy released as heat when a substance undergoes complete combustion with oxygen under standard conditions.

Heavy water (deuterium oxide, 2H2O) is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium (2H or D, also known as heavy hydrogen), rather than the common hydrogen-1 isotope (1H or H, also called protium) that makes up most of the hydrogen in normal water.

This is a list of the different types of particles found or believed to exist in the whole of the universe.

In nuclear physics and nuclear chemistry, nuclear fission is either a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into smaller parts (lighter nuclei).

A nuclide (from nucleus) is an atomic species characterized by the specific constitution of its nucleus, i.

In particle physics, the strong interaction is the mechanism responsible for the strong nuclear force (also called the strong force, nuclear strong force), and is one of the four known fundamental interactions, the others are electromagnetism, the weak interaction and gravitation.

The transuranium elements (also known as transuranic elements) are the chemical elements with atomic numbers greater than 92 (the atomic number of uranium).

In particle physics, the weak interaction (the weak force or weak nuclear force) is one of the four known fundamental interactions of nature, alongside the strong interaction, electromagnetism, and gravitation.

The abundance of a chemical element is a measure of the occurrence of the element relative to all other elements in a given environment.

Neutronium (sometimes shortened to neutrium) is a proposed name for a substance composed purely of neutrons.

In nuclear physics and nuclear chemistry, a nuclear reaction is semantically considered to be the process in which two nuclei, or else a nucleus of an atom and a subatomic particle (such as a proton, neutron, or high energy electron) from outside the atom, collide to produce one or more nuclides that are different from the nuclide(s) that began the process.

Cold fusion is a hypothesized type of nuclear reaction that would occur at, or near, room temperature.

A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is an atom that has excess nuclear energy, making it unstable.

The cross section is an effective area that quantifies the intrinsic likelihood of a scattering event when an incident beam strikes a target object, made of discrete particles.

Electron capture (K-electron capture, also K-capture, or L-electron capture, L-capture) is a process in which the proton-rich nucleus of an electrically neutral atom absorbs an inner atomic electron, usually from the K or L electron shell.

Positron emission or beta plus decay (β+ decay) is a subtype of radioactive decay called beta decay, in which a proton inside a radionuclide nucleus is converted into a neutron while releasing a positron and an electron neutrino (νe).

A temperature coefficient describes the relative change of a physical property that is associated with a given change in temperature.

Radioluminescence is the phenomenon by which light is produced in a material by bombardment with ionizing radiation such as alpha particles, beta particles, or gamma rays.

In chemistry, transactinide elements (also, transactinides, or super-heavy elements) are the chemical elements with atomic numbers from 104 to 120.

Nuclear fission products are the atomic fragments left after a large atomic nucleus undergoes nuclear fission.

The nuclear magnetic moment is the magnetic moment of an atomic nucleus and arises from the spin of the protons and neutrons.

Understanding the structure of the atomic nucleus is one of the central challenges in nuclear physics.

The nuclear force (or nucleon–nucleon interaction or residual strong force) is the force between protons and neutrons, subatomic particles that are collectively called nucleons.

Beta-decay stable isobars are the set of nuclides which cannot undergo beta decay, that is, the transformation of a neutron to a proton or a proton to a neutron within the nucleus.

Cold fission or cold nuclear fission is defined as involving fission events for which fission fragments have such low excitation energy that no neutrons or gammas are emitted.

Cosmogenic nuclides (or cosmogenic isotopes) are rare isotopes created when a high-energy cosmic ray interacts with the nucleus of an in situ Solar System atom, causing nucleons (protons and neutrons) to be expelled from the atom (see cosmic ray spallation).

The Max-Planck-Institut für Kernphysik ("MPI for Nuclear Physics" or MPIK for short) is aresearch institute in Heidelberg, Germany.

In nuclear physics, the valley of stability (also called the nuclear valley, energy valley, or beta stability valley) is a characterization of the stability of nuclides to radioactivity based on their binding energy.

Quantum hadrodynamics is an effective field theory pertaining to interactions between hadrons, that is, hadron-hadron interactions or the inter-hadron force.

Strangeness production is a signature and a diagnostic tool of quark–gluon plasma (or QGP) formation and properties.