First experiments on diffraction-enhanced imaging at LNLS.

Diffraction-enhanced images have been obtained using two silicon crystals in a non-dispersive set-up at the XRD2 beamline at the Brazilian Synchrotron Light Laboratory (LNLS). A first asymmetrically cut silicon crystal using the (333) reflection vertically expanded the monochromated beam from 1 mm to 20 mm allowing the imaging of the whole sample without movements. A symmetrically cut Si(333) second crystal was used as a Bragg analyzer.

Modelling the elastic scattering in diagnostic radiology: the importance of structure form factors.

The importance of structure form factors in describing elastic scattering in diagnostic radiology was studied through a Monte Carlo code built to reproduce scattering in large water samples. The code, developed by us, considers all relevant interactions, including multiple scattering and interference due to scattering by the liquid structure. Geometrical conditions and energies similar to those found in radiology were used.

Angle-dispersive diffraction with synchrotron radiation at Laboratório Nacional de Luz Síncrotron (Brazil): potential for use in biomedical imaging.

At low angles the scattering of X-rays in the diagnostic energy range (low-momentum transfer), it is probable that the scattering interaction will be coherent. This coherence gives rise to interference effects resulting in X-ray diffraction patterns that are characteristic of the scattering material. The usefulness of coherent scattering is not limited to crystallography.

Scattering of 60 keV photons by biological material and influence in diagnostic radiology.

The angular and energy distributions of photons scattered by water, muscle tissue, and bone were measured at the Physics Institute of the Universidade Federal do Rio de Janeiro using a Ge-detector and a 241Am source of 59.54 keV radiation. Single and double scattering were investigated on samples up to 16 cm in diameter.