90:, on the order of 0.01% to 0.1% of the total mass, may be absorbed or liberated as radiation. By working in terms of the mass excess, much of the mass changes which arise from the transfer or release of nucleons is effectively removed, highlighting the net energy difference.
70:(which defines the dalton). If the mass excess is negative, the nucleus has more binding energy than C, and vice versa. If a nucleus has a large excess of mass compared to a nearby nuclear species, it can
225:, which shows that the mass excess of the products is less than that of the reactants, and so the fission can occur – a calculation which could have also been done with only the masses of the reactants.
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factor is typically omitted when quoting mass excess values in MeV, since the interest is more often energy and not mass; if one wanted units of mass, one would simply change the units from MeV to MeV/
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The C standard provides a convenient unit (the dalton) in which to express nuclear mass for defining the mass excess. However, its usefulness arises in the calculation of nuclear reaction
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is well approximated (less than 0.1% difference for most nuclides) by its mass number, which indicates that most of the mass of a nucleus arises from mass of its constituent
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are quite large (even the proton mass is ~938.27 MeV/c), while mass excesses range in the tens of MeV/
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or decay. Only a small fraction of the total energy that is associated with an atomic nucleus by
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technology. The combination of this practical point with the theoretical relation
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Nuclear reaction kinematics are customarily performed in units involving the
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makes the unit megaelectronvolt over the speed of light squared (MeV/
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Audi, G.; Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S. (2017).
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Difference between actual mass and mass number for nuclei
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of the reactant, U, is 236. Because the actual mass is
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291:Tipler, P. A; Llewellyn, R. A. (2004).
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350:10.1088/1674-1137/41/3/030001
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270:Introductory Nuclear Physics
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297:W. H. Freeman and Company
88:mass–energy equivalence
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274:John Wiley & Sons
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268:Krane, K. S (1987).
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72:radioactively decay
372:Nuclear chemistry
330:Chinese Physics C
147:U → Kr + Ba + 3 n
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361:Categories
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84:kinematics
230:1 Da
68:carbon-12
223: Da
215: Da
206: Da
198: Da
188: Da
180: Da
172: Da
56:neutrons
338:Bibcode
157:236.045
135:Example
64:nucleon
52:protons
44:daltons
36:nuclide
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326:(PDF)
219:0.179
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34:of a
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236:MeV/
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