News tagged with neutrons
A new way to discover pulsars
(Phys.org) -- The Large Area Telescope (LAT), built by SLAC for the Fermi Gamma-ray Space Telescope, collects information on high-energy gamma rays from numerous sources in the sky. Among these are small, ...
May 22, 2012 |
5 / 5 (6) |
1
|
A supernova cocoon breakthrough
(Phys.org) -- Observations with NASA's Chandra X-ray Observatory have provided the first X-ray evidence of a supernova shock wave breaking through a cocoon of gas surrounding the star that exploded. This discovery ...
May 15, 2012 |
4.8 / 5 (6) |
0
|
The use of acoustic inversion to estimate the bubble size distribution in pipelines
New research from the University of Southampton has devised a new method to more accurately measure gas bubbles in pipelines.
May 15, 2012 |
3 / 5 (1) |
0
Spin polarized supercurrents optimized with a simple flip
(Phys.org) -- Researchers from Michigan State University, the NIST Center for Neutron Research, and the NIST Center for Nanoscale Science and Technology have discovered the key to controlling and enhancing ...
May 14, 2012 |
5 / 5 (3) |
0
Neutron scattering charts moves of memory-shape alloys that change structure in response to environmental cues
(Phys.org) -- Shape-memory alloys (SMAs) are an engineer's dream, able to shape-shift spontaneously to accommodate changing operating conditions. A research team from the National Aeronautics and Space Administration ...
May 09, 2012 |
5 / 5 (1) |
0
|
NASA's Chandra sees remarkable outburst from old black hole
An extraordinary outburst produced by a black hole in a nearby galaxy has provided direct evidence for a population of old, volatile stellar black holes. The discovery, made by astronomers using NASA's Chandra ...
Apr 30, 2012 |
4.3 / 5 (7) |
1
|
Neutrons used to study a key protein in milk
Martha, a cow placidly grazing in a field in The Netherlands, became an important collaborator with researchers who successfully analyzed and characterized the internal protein structure and the composite ...
Chemistry / Analytical Chemistry
Apr 24, 2012 |
not rated yet |
0
Dawn gets extra time to explore Vesta
(Phys.org) -- NASA's Dawn mission has received official confirmation that 40 extra days have been added to its exploration of the giant asteroid Vesta, the second most massive object in the main asteroid belt. ...
Space & Earth / Space Exploration
Apr 19, 2012 |
5 / 5 (4) |
6
|
Neutron generation: Going from tubes to chips
(Phys.org) -- It was a figurative whack on the head that started Sandia National Laboratories distinguished technical staff member Juan Elizondo-Decanini thinking outside the box -- which in his case was a ...
Apr 17, 2012 |
4.8 / 5 (19) |
7
|
Two neutrons at the same time: Discovery of dineutron decay
(Phys.org) -- Nuclear physicists recently witnessed an atomic nucleus do something that nobody had ever seen one do before – two neutrons at the same time.
Apr 12, 2012 |
5 / 5 (25) |
5
|
End of the magic: Shell model for beryllium isotopes invalidated
A research group led by Professor Dr. Wilfried Nortershäuser has, for the first time, managed to measure the size of the charge distribution in the atomic nucleus of the highly exotic beryllium-12 isotope. ...
Apr 05, 2012 |
5 / 5 (5) |
4
|
Novel filter metal-organic framework material could cut natural gas refining costs
A new type of hybrid material developed at the University of California, Berkeley, could help oil and chemical companies save energy and money – and lower their environmental impacts – by eliminating ...
Mar 29, 2012 |
5 / 5 (6) |
1
|
Powerhouse in the Crab Nebula
MAGIC telescopes measure the highest-energy gamma rays from a pulsar to date, calling theory into question.
Mar 29, 2012 |
5 / 5 (6) |
16
|
Neutrons uncover new density waves in fermion liquids
Scientists working at the Institut Laue-Langevin, one of the world's leading centres for neutron science, have carried out the first investigation of two-dimensional fermion liquids using neutron scattering, and discovered ...
Mar 28, 2012 |
4.3 / 5 (3) |
0
|
Launch of NASA's nuSTAR mission postponed
(PhysOrg.com) -- The planned launch of NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) mission has been postponed after a March 15 launch status meeting. The launch will be rescheduled to allow additional ...
Space & Earth / Space Exploration
Mar 19, 2012 |
not rated yet |
0
Neutron
The neutron is a subatomic hadron particle which has the symbol n or n0, no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of protons in a nucleus is the atomic number and defines the type of element the atom forms. Neutrons are necessary within an atomic nucleus as they bind with protons via the strong force; protons are unable to bind with each other due to their mutual electromagnetic repulsion being stronger than the attraction of the strong force. The number of neutrons is the neutron number and determines the isotope of an element. For example, the abundant carbon-12 isotope has 6 protons and 6 neutrons, while the very rare radioactive carbon-14 isotope has 6 protons and 8 neutrons.
While bound neutrons in stable nuclei are stable, free neutrons are unstable; they undergo beta decay with a mean lifetime of just under 15 minutes (881.5±1.5 s). Free neutrons are produced in nuclear fission and fusion. Dedicated neutron sources like research reactors and spallation sources produce free neutrons for use in irradiation and in neutron scattering experiments. Even though it is not a chemical element, the free neutron is sometimes included in tables of nuclides. It is then considered to have an atomic number of zero and a mass number of one, and is sometimes referred to as neutronium.[citation needed]
The neutron has been the key to nuclear power production. After the neutron was discovered in 1932, it was realized in 1933 that it might mediate a nuclear chain reaction. In the 1930s, neutrons were used to produce many different types of nuclear transmutations. When nuclear fission was discovered in 1938, it was soon realized that this might be the mechanism to produce the neutrons for the chain reaction, if the process also produced neutrons, and this was proven in 1939, making the path to nuclear power production evident. These events and findings led directly to the first man-made nuclear chain reaction which was self-sustaining (Chicago Pile-1, 1942) and to the first nuclear weapons (1945).
For more information about Neutron, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
