>If projects a middle-C-tone into a piano, do all of the lower notes resonate as well, according to the Kramers-Kronig relation?
If you press the right pedal the harmonics of the note you play will resonate. My piano teachers never mentioned to me the Kramers-Kronig relation but that's a long time ago, perhaps they do these days.
Right, I always understood that it was just the harmonics which would resonate. But according to Kramers-Kronig, wouldn't there be resonance on all strings, just as there's anomalous scattering at all higher energies above the edge? Each string of lower frequency would be analogous to an anomalous scatterer with an edge at a lower energy than the incident radiation. Hmm, maybe it really does happen?
A different question: do the real and imaginary components of anomalous scattering arise from different processes, or are they simply a way to represent the phase of the anomalous scattering?
All the best,
Jacob
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From: CCP4 bulletin board [[log in to unmask]] on behalf of Keller, Jacob [[log in to unmask]]
Sent: Wednesday, March 11, 2015 6:57 PM
To: [log in to unmask]
Subject: [ccp4bb] Basic Anomalous Scattering Theory
Dear Crystallographers,
I have had only a vague understanding of what specific things are happening with shell electrons at anomalous edges. Specifically, for example, to what energy of electron-transition does the x-ray k-edge correspond in terms of orbitals, and is that transition energy actually equal to the energy of the photon, suggesting that the photon is absorbed (or disappears?) in elevating the electron? I don't think we say it is absorbed, so how does the energy come back out, from the electron's falling back down, right? So then there's a new photon created, or the same one comes back out? Where was it?
Further, I also have heard that the emerging anomalous/resonance photons are of the same wavelength as the incident radiation, but usually there is something lost in transitions (even non-fluorescence ones) I thought? Has it ever been definitively shown that the anomalous photons are of the same energy as the incident radiation?
In the case of L-edges, why are there three separate edges? Further, if the resonance occurs when the energies are equal, why does resonance occur at energies greater than the edge? I don't think this happens in other resonance phenomena, or does it? If projects a middle-C-tone into a piano, do all of the lower notes resonate as well, according to the Kramers-Kronig relation? I think it may actually happen in the mammalian cochlea's travelling wave, but is it completely general to resonance phenomena?
Just interested, and have wondered these things for a long time in the background of my mind...
Jacob Keller
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Jacob Pearson Keller, PhD
Looger Lab/HHMI Janelia Research Campus
19700 Helix Dr, Ashburn, VA 20147
email: [log in to unmask]
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