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  2. Radioactive decay - Wikipedia

    en.wikipedia.org/wiki/Radioactive_decay

    the equation indicates that the decay constant λ has units of t −1, and can thus also be represented as 1/ τ, where τ is a characteristic time of the process called the time constant. In a radioactive decay process, this time constant is also the mean lifetime for decaying atoms.

  3. Radiometric dating - Wikipedia

    en.wikipedia.org/wiki/Radiometric_dating

    Radiometric dating. Radiometric dating, radioactive dating or radioisotope dating is a technique which is used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed. The method compares the abundance of a naturally occurring radioactive isotope within the material to ...

  4. Half-life - Wikipedia

    en.wikipedia.org/wiki/Half-life

    Rutherford applied the principle of a radioactive element's half-life in studies of age determination of rocks by measuring the decay period of radium to lead-206. Half-life is constant over the lifetime of an exponentially decaying quantity, and it is a characteristic unit for the exponential decay equation.

  5. Decay chain - Wikipedia

    en.wikipedia.org/wiki/Decay_chain

    v. t. e. In nuclear science, the decay chain refers to a series of radioactive decays of different radioactive decay products as a sequential series of transformations. It is also known as a "radioactive cascade". The typical radioisotope does not decay directly to a stable state, but rather it decays to another radioisotope.

  6. Decay energy - Wikipedia

    en.wikipedia.org/wiki/Decay_energy

    The decay energy is the mass difference Δm between the parent and the daughter atom and particles. It is equal to the energy of radiation E. If A is the radioactive activity, i.e. the number of transforming atoms per time, M the molar mass, then the radiation power P is: or. or. Example: 60 Co decays into 60 Ni. The mass difference Δm is 0.003 u.

  7. Positron emission - Wikipedia

    en.wikipedia.org/wiki/Positron_emission

    Nuclear physics. Positron emission, beta plus decay, or 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). [1] Positron emission is mediated by the weak force.

  8. Alpha decay - Wikipedia

    en.wikipedia.org/wiki/Alpha_decay

    v. t. e. 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 a different atomic nucleus, with a mass number that is reduced by four and an atomic number that is reduced by two. An alpha particle is identical to the nucleus of a helium ...

  9. Radiocarbon dating - Wikipedia

    en.wikipedia.org/wiki/Radiocarbon_dating

    The equation governing the decay of a radioactive isotope is: [5] = where N 0 is the number of atoms of the isotope in the original sample (at time t = 0, when the organism from which the sample was taken died), and N is the number of atoms left after time t.