# Tag Info

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What if we introduced a neutron poison into the plasma, such as Xe135 or B10 The amount of energy lost from the plasma varies with the mass of the particles within it. This is why the divertor and scrape-off systems are so important, otherwise heavier atoms spalled off the reactor walls murder your energy balance by increasing the x-ray emission. So, ...

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Yes, nucleons have excited states and resonances. The two middle delta baryons are the most well-known with spin 3/2 instead of 1/2 for the proton and neutron, followed by the Roper resonances. There is a fairly long list of such states by now, running up to 2700 MeV and 13/2 spin for nucleons.

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Note that the question asked Where does the mass coming from when neutrons are produced from protons. A neutron is basically(*) a proton+electron. So the mass was already there as an electron and it basically merged with a proton to form the neutron. As others correctly explained, when protons and neutrons bind into a nucleus they release energy. E=MC^2, ...

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Neutron and antineutron have also an internal structure formed by quarks. A neutron is composed by 2 down quarks, each with a charge -1/3, and one up quark with a charge of 2/3. This gives a total charge of 0. Antineutron are different, they have 2 anti-down quarks (each with a charge of 1/3) and one antiup quark (-2/3) of charge. So, even though they have ...

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The sun loses about 4 million tons per second in mass. This is largely in the form of light (which has a mass from E=mc^2), and charged particles such as helium nuclei.

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Stars fuse hydrogen (bare protons) to helium (two protons and two neutrons). But the reaction has a number of intermediate steps. The first step fuses two protons to deuterium, and a positron and a neutrino: $$^1_1H + ^1_1H ~ \rightarrow ~ ^2_1H + e^+ + \nu_e$$ You are correct that a neutron has higher rest mass than a proton, but this reaction never ...

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No it is decreasing in mass. You must take into account binding energy in the atom core. The protons and neutrons are bound together really strongly by the strong nuclear force inside the core of a Helium atom. It takes lots and lots of energy to try to pull them apart. Firstly you must overcome electromagnetic force to push them together so closely ...

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While a free neutron does have more mass than a free proton, a bound helium-4 nucleus has less mass than two free protons and two free neutrons. In fact, the helium-4 nucleus has less mass than four free protons. The difference goes into the binding energy of the nucleus. Therefore, as the other answers state correctly, stars are constantly losing mass, not ...

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Yes, the conversion from hydrogen to helium by nuclear fusion releases energy at the expense of the products having less mass than the reactants. The linking equation between energy and loss of mass was proposed by Einstein, $E= \Delta m\,c^2$. The numbers are quite astronomical. Due to nuclear fusion the Sun loses about 4 million tonnes ($4\,000\,000\... 30 In fact, the Sun is losing mass all the time. It radiates large amounts of energy, and through the energy-mass relationship$E = m c^2\$, radiating energy means radiating mass. Since the mass of a helium atom is less than the mass of the four free protons which enter the fusion process, one can consider fusion the process of converting mass into energy.

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One stable isotope that contains fewer neutrons than protons is helium-3( 2 protons, 1 neutron). But in general, a larger number of neutrons acts to balance the strong nuclear attractive force with the repulsive electric force of the protons. When nuclei get to a large enough size, they become unstable (radioactive) without extra neutrons, and for even ...

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The conventional explanation of more no of neutrons in nuclei is that because protons repel each other through the electrostatic force they must be diluted by neutrons. The conventional theory of nuclear structure maintains that all nucleons are attracted to each other through the so-called strong force. And they will balance the electrostatic repulsion of ...

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