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Mar
22
comment Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
For example, the question asserts that Auger deuteron emission is far more likely than Auger electron emission. Therefore, the fact that X-ray emission is likelier than electron emission, as you say, does not preclude the possibility that deuteron emission is more likely than either. You are entitled to argue that the question's assertion is wrong, but that's not what you did. You just ignored the assertion ... as if you hadn't even read the question.
Mar
22
comment Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
@DavePhD -- The muon is a postulated seed -- the main question is about the chain reaction, not the seed. The chain reaction is indeed supposed to involve fast charged alpha particles, not x-rays. The fusion chain reaction is supposed to happen in a room-temperature tabletop apparatus, not in a billion-dollar facility like NIF or ITER. (Have you heard of cold fusion? You need to look it up if you want to understand the question.) Anyway, from everything you've written, I get the strong impression that you don't understand the question being asked. You should re-read the question.
Mar
20
comment Band gaps: are they at the centre or at the edge of the Brillouin zone?
If I have a transition from the center of the first BZ, to the boundary between the second and third BZ, I would NOT describe this transition as a "band gap ... at the edge of the BZ".
Mar
20
comment Band gaps: are they at the centre or at the edge of the Brillouin zone?
You're not missing anything. What you said is correct. I have no idea what that quotation could be talking about. Need more context. Maybe it's talking about something very specific, i.e. a specific model of a specific system, rather than band gaps in general.
Mar
19
comment Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
Ron emailed me. Summary: One K-shell hole is enough energy, but the deuterons would be too far from the Pd nucleus for it to participate. So an electron would have to be the 3rd body instead. This is possible but there are some reasons to think it is less likely. About kinetics and stability: He says there is a series of micro-explosions. Maybe each explosion is centered on a region of unusually high D-density (drawn by a low electric potential), and the reaction can't engulf the whole electrode because D density is lower elsewhere, below $B/A$. There is more discussion I'm leaving out. :-P
Mar
18
awarded  Revival
Mar
18
revised Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
clarify
Mar
17
comment What is the area in Faraday's law if we have only a piece of metal moving in a magnetic field?
You should define E*...
Mar
17
comment What is the area in Faraday's law if we have only a piece of metal moving in a magnetic field?
You're describing a "homopolar generator". There is a discussion of how Faraday's law does (not) apply to homopolar generators at: en.wikipedia.org/wiki/…
Mar
17
answered Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
Mar
17
comment Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
See "The Theory of Auger Transitions" by Chattarji, p 16-19: "Physically, the perturbation causing the [Auger] transition arises from the Coulomb interaction between neighboring electrons ... We must point out here another reason for considering the [Auger] effect to be a radiationless transition rather than a conversion process..." etc. etc. The discussion is detailed and thorough. (Of course, Auger emission involves virtual photons, like any electromagnetic interaction. And there are retardation corrections etc., i.e. not exactly "electrostatic". But no real photon is involved.)
Mar
16
reviewed Approve suggested edit on When I stretch a rubber band, it breaks. When I hold the broken ends together, why doesn't it join again?
Mar
16
reviewed Approve suggested edit on Why does a candle blow out when we blow on it? Our breath is 16% oxygen and only 4% CO2
Mar
16
comment Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
In the mechanism under discussion, the (alleged) inner-shell holes are created not by x-rays but by fast charged particles. A 20MeV alpha could theoretically create a hundred 20keV deuterons by slamming into them all almost dead-on, but this is extraordinarily unlikely. OTOH, if the alpha is traveling through Pd, it can quite frequently create a hundred inner-shell holes. ALSO, this is allegedly a three-body fusion process where the palladium atom is one of the bodies. So in summary I don't know how you could say that the palladium lattice is not helping ... it's critical!
Mar
16
comment Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
A deuteron cannot just absorb an x-ray and wind up with extra kinetic energy. Such a process cannot satisfy energy-momentum conservation. (Proof: Think about it in the center-of-mass frame.) That's why your description of ordinary Auger emission -- first an x-ray is literally emitted, then another electron absorbs it -- cannot be correct, even if you found a book that says it. The book is wrong, it's electrostatic. If you look at theoretical papers calculating Auger rates and shifts you'll find that specialists agree it's electrostatic.
Mar
14
awarded  Investor
Mar
11
comment Getting nonphysical results when solving for the index of refraction of a slab?
@YungHummmma -- No, I don't know what he was talking about. This is not a near-field measurement. The light source and detector are both many many wavelengths away from the sample.
Mar
11
comment Getting nonphysical results when solving for the index of refraction of a slab?
I suspect that you're taking your data too literally. It would not be at all surprising for this kind of data to be systematically shifted up or down a bit compared to reality. Mirrors may not be perfectly reflective, samples can scatter some light, optics may not be perfectly aligned, some light might hit the non-suspended part of your sample, etc. You need more constraints in your fitting -- not only $n_r > 0$ but also assuming some functional form consistent with kramers-kronig.
Mar
11
comment Getting nonphysical results when solving for the index of refraction of a slab?
Plane wave model is fine. For example, in ellipsometry, you use a plane wave model to characterize oxide layers that are one or two atoms thick!
Mar
11
revised Phonon scattering process in raman spectroscopy
deleted 11 characters in body