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  2. Gamma ray - Wikipedia

    en.wikipedia.org/wiki/Gamma_ray

    Gamma emission spectrum of cobalt-60. One example of gamma ray production due to radionuclide decay is the decay scheme for cobalt-60, as illustrated in the accompanying diagram. First, 60 Co decays to excited 60 Ni by beta decay emission of an electron of 0.31 MeV. Then the excited 60 Ni

  3. Photodisintegration - Wikipedia

    en.wikipedia.org/wiki/Photodisintegration

    The incoming gamma ray effectively knocks one or more neutrons, protons, or an alpha particle out of the nucleus. [1] The reactions are called (γ,n), (γ,p), and (γ,α). Photodisintegration is endothermic (energy absorbing) for atomic nuclei lighter than iron and sometimes exothermic (energy releasing) for atomic nuclei heavier than iron .

  4. Commonly used gamma-emitting isotopes - Wikipedia

    en.wikipedia.org/wiki/Commonly_used_gamma...

    It has a half-life of 30 years, and decays by beta decay without gamma ray emission to a metastable state of barium-137 (137m Ba). Barium-137m has a half-life of a 2.6 minutes and is responsible for all of the gamma ray emission in this decay sequence. The ground state of barium-137 is stable. The photon energy (energy of a single gamma ray) of ...

  5. Nuclear isomer - Wikipedia

    en.wikipedia.org/wiki/Nuclear_isomer

    A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excited state levels (higher energy levels). ). "Metastable" describes nuclei whose excited states have half-lives 100 to 1000 times longer than the half-lives of the excited nuclear states that decay with a "prompt" half life (ordinarily on the order of 10

  6. Decay energy - Wikipedia

    en.wikipedia.org/wiki/Decay_energy

    Pu on almost all measures, being shorter lived, a beta emitter rather than an easily shielded alpha emitter and releasing significant gamma radiation when its daughter nuclide 90 Y decays, but as it is a high yield product of nuclear fission and easy to chemically extract from other fission products, Strontium titanate based RTGs were in ...

  7. Iodine-123 - Wikipedia

    en.wikipedia.org/wiki/Iodine-123

    Iodine-123 (123 I) is a radioactive isotope of iodine used in nuclear medicine imaging, including single-photon emission computed tomography (SPECT) or SPECT/CT exams. The isotope's half-life is 13.2232 hours; [1] the decay by electron capture to tellurium-123 emits gamma radiation with a predominant energy of 159 keV (this is the gamma primarily used for imaging).

  8. Neutron activation - Wikipedia

    en.wikipedia.org/wiki/Neutron_activation

    If the fission requires an input of energy, that comes from the kinetic energy of the neutron. An example of this kind of fission in a light element can occur when the stable isotope of lithium, lithium-7, is bombarded with fast neutrons and undergoes the following nuclear reaction: 7 3 Li + 1 0 n → 4 2 He + 3 1 H + 1 0 n + gamma rays ...

  9. Electron–positron annihilation - Wikipedia

    en.wikipedia.org/wiki/Electron–positron...

    In the most common case, two gamma photons are created, each with energy equal to the rest energy of the electron or positron (0.511 MeV). [2] A convenient frame of reference is that in which the system has no net linear momentum before the annihilation; thus, after collision, the gamma photons are emitted in opposite directions.