Recent content by avkr

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    Undergrad End Point Energy and Q value in beta decay

    Okay, but can you define exactly what endpoint energy is. In the article: https://www.nucleonica.com/wiki/index.php?title=Endpoint_energy, it says ##E_0 = Q + m_e c^2## which is "mass difference between the parent and daughter nuclides" for beta decay. So endpoint energy is not the maximum...
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    Undergrad End Point Energy and Q value in beta decay

    I have edited the question and attached the lecture slide I am reading. I think I'm getting confused about the definition of endpoint energy. Is it the maximum kinetic energy of electron observed or the total relativistic energy of the beta particle.
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    Undergrad End Point Energy and Q value in beta decay

    I know that Q value of a reaction is the difference between total initial mass-energy and total final mass-energy of all the products. Then shouldn't be this also the maximum kinetic energy and hence endpoint energy of an electron in beta decay. But what I have read endpoint energy ##E_0 = Q +...
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    Undergrad Rotational Spectra: ΔJ Selection Rule & Emission Part

    The selection rule for rotational spectra ##ΔJ = ±1##. Is it always true for the emission part of rotation spectra ##ΔJ = -1## and how?
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    How Does Dipole-Dipole Interaction Affect H₂ Molecule's Ground State Energy?

    Homework Statement Consider an ##H_2## molecule where the protons are separated by a wide distance R and both are located on the z-axis. Ignoring the spin degrees of freedom and treating the dipole-dipole interaction as a perturbation, use perturbation theory to estimate an upper limit for the...
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    Undergrad Fluorescence from core shell quantum dots

    What is the reason for enhancement in the intensity of emission due to the introduction of a shell in quantum dots? I do understand the blue shift in quantum dots but how does a shell enhance it?
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    What is the Threshold Energy of a Neutrino in the Centre of Mass Frame?

    I have included e0 as energy of neutrino whereas sqrt(m_n^2 c^4 + e0^2) contains the terms rest mass of neutron (m_n^2 c^4) and e0^2 is the (pc)^2 term ( p = e0/c, therefore (pc)^2 = e0^2).
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    What is the Threshold Energy of a Neutrino in the Centre of Mass Frame?

    Homework Statement Mass of neutrino = 0 Mass of proton/neutron = 1 GeV Mass of tau = 2 GeV Homework Equations Energy of neutrino in lab = e Energy of neutrino in CM = e0 The Attempt at a Solution In the centre of mass frame, we will take the momentum of the neutron to be e0/c, c = speed of...