Mössbauer spectroscopy is a spectroscopic<http://en.wikipedia.org/wiki/Spectroscopy>technique based on the recoil-free, resonant absorption and emission of gamma rays <http://en.wikipedia.org/wiki/Gamma_ray> in solids<http://en.wikipedia.org/wiki/Solid>. This resonant emission and absorption was first observed by Rudolf Mössbauer<http://en.wikipedia.org/wiki/Rudolf_M%C3%B6ssbauer>during his graduate studies in 1957, and is called the Mössbauer effect <http://en.wikipedia.org/wiki/M%C3%B6ssbauer_effect> in his honor. Mössbauer received a Nobel Prize in 1961 for this work.
Like NMR spectroscopy <http://en.wikipedia.org/wiki/NMR_spectroscopy>, Mössbauer spectroscopy probes tiny changes in the energy levels of an atomic nucleus in response to its environment. Typically, three types of nuclear interaction <http://en.wikipedia.org/wiki/Nuclear_interaction> may be observed: an isomer shift <http://en.wikipedia.org/wiki/Isomer_shift>, also known as a chemical shift <http://en.wikipedia.org/wiki/Chemical_shift>; quadrupole splitting <http://en.wikipedia.org/wiki/Quadrupole_splitting>; and, magnetic or hyperfine splitting <http://en.wikipedia.org/wiki/Hyperfine_splitting>, also known as the Zeeman effect <http://en.wikipedia.org/wiki/Zeeman_effect>. Due to the high energy and extremely narrow line<http://en.wikipedia.org/wiki/Spectral_line>widths of gamma rays, Mössbauer spectroscopy is one of the most sensitive techniques in terms of energy (and hence frequency) resolution, capable of detecting change in just a few parts per 10e11. Depending on the local environment of the Fe atoms and the magnetic properties, Mössbauer spectra of iron oxides can consist of a singlet, a doublet, or a sextet. If the iron is superparamagnetic a telltale hyperfine sextet structure will be detected. On Thu, Apr 14, 2011 at 11:26 PM, francis <froarty...@comcast.net> wrote: > Jed wrote [snip] > > Focardi says some things that are supposed to be confidential. I will leave > > it to the reader to find those bits, as an exercise. He's got a big mouth. > > I'll bet this ruffles some feathers![/snip] > > > > Focardi says “and then there's this chemical compound. The issue came up > during that demonstration because, when some people tried to measure the > gamma rays, Rossi objected, because by measuring the gamma rays they would > have also measured the gamma rays emitted by this secret compound, and so > they would have understood what it was, what was in it.” > > > > He is revealing that it is a chemical compound that emits gamma rays…. That > it participates in the nuclear reaction? > > > > Fran > > > > >
