Fundamental research with neutrons: Ultracold neutrons, Interferometry
Fast neutron therapy
Neutron capture therapy
Infrastructure
Neutron sources: Research reactor, Spallation, Neutron moderator
Neutron optics: Reflector, Supermirror
Detection
Neutron facilities
America: HFIR, LANSCE, NIST CNR -SNS
Australia: OPAL
Asia: J-PARC, HANARO
Europe: BER II, FRM II, ILL, ISIS Neutron and Muon Source, JINR, SINQ
Historic: IPNS, HFBR
Under construction: ESS
v
t
e
Neutron capture is a nuclear reaction in which an atomic nucleus and one or more neutrons collide and merge to form a heavier nucleus.[1] Since neutrons have no electric charge, they can enter a nucleus more easily than positively charged protons, which are repelled electrostatically.[1]
Neutron capture plays a significant role in the cosmic nucleosynthesis of heavy elements. In stars it can proceed in two ways: as a rapid process (r-process) or a slow process (s-process).[1] Nuclei of masses greater than 56 cannot be formed by thermonuclear reactions (i.e., by nuclear fusion) but can be formed by neutron capture.[1]
Neutron capture on protons yields a line at 2.223 MeV predicted[2] and commonly observed[3] in solar flares.
^ abcdAhmad, Ishfaq; Hans Mes; Jacques Hebert (1966). "Progress of theoretical physics: Resonance in the Nucleus". Institute of Physics. 3 (3): 556–600.
^
Morrison, P. (1958). "On gamma-ray astronomy". Il Nuovo Cimento. 7 (6): 858–865. Bibcode:1958NCim....7..858M. doi:10.1007/BF02745590. S2CID 121118803.
^Chupp, E.; et al. (1973). "Solar Gamma Ray and Neutron Observations". NASA Special Publication. 342: 285. Bibcode:1973NASSP.342..285C.
Neutroncapture is a nuclear reaction in which an atomic nucleus and one or more neutrons collide and merge to form a heavier nucleus. Since neutrons...
Neutroncapture therapy (NCT) is a type of radiotherapy for treating locally invasive malignant tumors such as primary brain tumors, recurrent cancers...
incident neutron. Nuclides that tend to absorb a neutron and either decay or keep the neutron in its nucleus are neutron absorbers and will have a capture cross...
Neutron activation is the process in which neutron radiation induces radioactivity in materials, and occurs when atomic nuclei capture free neutrons, becoming...
The neutron detection temperature, also called the neutron energy, indicates a free neutron's kinetic energy, usually given in electron volts. The term...
Neutron radiation is a form of ionizing radiation that presents as free neutrons. Typical phenomena are nuclear fission or nuclear fusion causing the release...
of undergoing nuclear fission (even with a low probability) after capturing a neutron of high or low energy is referred to as fissionable. A fissionable...
relatively low neutron flux on the order of 105 to 1011 cm−2 s−1, resulting in nucleosynthesis by the s-process (slow neutron-capture process). By contrast...
poisons deplete as they absorb neutrons during reactor operation, while others remain relatively constant. The capture of neutrons by short half-life fission...
engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, ideally without capturing any, leaving them as thermal neutrons with only...
remnants except if ejected through stellar winds and explosions. The neutroncapture reactions of the r-process and s-process create heavier elements, from...
an artificial element, except for trace quantities resulting from neutroncapture by uranium, and thus a standard atomic weight cannot be given. Like...
stable isotopes, one of which (boron-10) has a number of uses as a neutron-capturing agent. The intersection of boron with biology is very small. Consensus...
Neutron activation analysis (NAA) is a nuclear process used for determining the concentrations of elements in many materials. NAA allows discrete sampling...
Neutroncapture nucleosynthesis describes two nucleosynthesis pathways: the r-process and the s-process, for rapid and slow neutroncaptures, respectively...
average time from a neutron emission to a capture that results in fission. The mean generation time is different from the prompt neutron lifetime because...
sample from its 235U deficit. This made it possible to estimate the neutroncapture by the isotopes 143Nd and 145Nd, leading to the additional formation...
Neutron detection is the effective detection of neutrons entering a well-positioned detector. There are two key aspects to effective neutron detection:...
A neutron bomb, officially defined as a type of enhanced radiation weapon (ERW), is a low-yield thermonuclear weapon designed to maximize lethal neutron...
differences in neutroncapture cross sections and gamma spectroscopy and nuclear magnetic resonance properties. If too many or too few neutrons are present...
134Xe is stable) as a fission product and via neutroncapture from nonradioactive 133Cs (neutroncapture cross section 29 barns), which is a common fission...
before accounting for the effects of any subsequent neutroncapture; e.g.: 135Xe capturing a neutron and becoming nearly stable 136Xe, rather than decaying...
Global Information