Compton distribution

The radionuclide emits a high-energy gamma ray at 6.13 MeV. A gamma-ray spectrum of a soiurce exhibits peaks at 5.62 MeV, 5.11 MeV, and 0.511 MeV in addition to the FEP at 6.13 MeV and the usual Compton distribution. Assuming these features are not due to primary gamma rays emitted in the decay of N, how would you explain the existence of these three extra peaks ... 

The resolution of Nal (Tl) spectrometers depends on the energy of the radiation. At energies of about 10 MeV when the response in the crystal is mainly due to pair production, the resolution is about 10%. A slight difficulty in interpretation arises from the presence of subsidiary peaks due to escape of one or both of the pair annihilation quanta. At lower energies the pair lines are also found but the Compton distribution becomes more important and the pair peaks are superimposed on this. At energies below the pair threshold there are pulses from the Compton recoil electrons and from photoelectrons and as the quantum energy decreases the photoelectric peak becomes more important but the resolution decreases, as E, until it is only of the order of 20 to 30% for 50keV quanta. 

Crystal can compute a number of properties, such as Mulliken population analysis, electron density, multipoles. X-ray structure factors, electrostatic potential, band structures, Fermi contact densities, hyperfine tensors, DOS, electron momentum distribution, and Compton profiles. 

A somewhat similar hut not identical electron distribution for these ions has been derived by A. H. Compton, Phys, Rev., vol. 27, p. 510 (1926), from the same experimental data. 

The Compton scattering cannot be neglected, but it is independent of molecular structure. Then, fitting experimental data to formulas from gas phase theory, the concentration of excited molecules can be determined. Another problem is that the undulator X-ray spectrum is not strictly monochromatic, but has a slightly asymmetric lineshape extending toward lower energies. This problem may be handled in different ways, for example, by approximating its spectral distribution by its first spectral moment [12]. 

Lundqvist, B.I. and Lyden, C. (1971) Calculated momentum distributions and Compton profiles of interacting conduction electrons in lithium and sodium, Phys. Rev., B4, 3360-3370. 

In the field of Compton scattering the real space function it B(r) for the electron system is defined by the Fourier inversion of the distribution function of electron... 

Mijnarends, P.E. (1977) Reconstruction of three-dimensional distribution, In Compton Scattering, Williams, B. (Ed.), McGraw-Hill, New York, pp. 323-345. 

Kobayasi, T., Nara, H., Timms, D.N. and Cooper, MJ. (1995) Core-orthogonalization effects on the momentum density distribution and the Compton profile of valence electrons in semiconductors, Bull. Coll. Med. Sci. Tohoku Univ., 4, 93-104. 

Hansen, H., (1980) Reconstruction of the electron momentum distribution from a set of experimental Compton profiles, Hahn Meitner Institute (Berlin), Report HMI B 342. 

The EMD is closely related to intensities obtained from Compton scattering experiments, in which the obtained distribution depends on the incident wavelength and the scattering angle. The intensity of the scattered radiation is proportional to the theoretically obtained Compton profile given by the equation... 

Bond oscillation principle In the spirit of the bond directionality principle advocated by Coulson, Kaijser and Smith [15] proposed that the momentum distributions and Compton profiles associated with the bond will exhibit oscillations. 

Compton DR, Bagley RB, Katzen JS, Martin BR. 1987. (-l-)-and (-)-N-aUylnormetazocine binding sites in mouse brain in vitro and in vivo characterization and regional distribution. Life Sci 40 2195-2206. 

Fig. 4.4. All-sky map in the light of the 1.809 MeV gamma-ray hne from radioactive aluminium-26. The galactic distribution of aluminium-26, based on data from the COMPTEL (Compton Telescope) experiment aboard the GRO (Gamma-Ray Observatory), suggests that this isotope is dispersed across the Galaxy by the most massive stars, Wolf-Rayet stars and supernovas. Al is formed by the reaction Mg -b p — A1 -b y. This radioactive isotope has a lifetime of about million years and is ejected into space before it begins to decay.

L. Mendelsohn and V. H. Smith, Jr., Atoms, in Compton Scattering The Investigation of Electron Momentum Distributions, B. G. Williams, ed. (McGraw-Hill, New York, 1977), pp. 103-138. 

As the column depth of the supernova ejecta decreases as t 2, 7-rays and hard X-rays suffer from less Compton scattering and photoelectric absorption and eventually emerge from the surface. The timing of their emergences and light curves are sensitive to E, Menv, and the distribution of elements. In other words, X-ray and 7-ray observations provide another good diagnosis of the supernova interior. 

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