Physics and Image Techniques (2006/2007)

Learning outcomes

Aim of the course is to give basic physics knowledge of image formation as regards different regions of the electromagnetic and acoustic waves spectrum. Particular care will be devoted to Medical Imaging techniques: optical and electronic microscopy; ultrasonic imaging; X-ray imaging: conventional radiography and TAC, gamma imaging: SPECT, PET; nuclear magnetic resonance imaging (MRI).

OPTICS

WAVES: wave equation, armonic waves, superposition principle, dispersion, intensity, mechanical and acoustic waves
ELECTROMAGNETIC WAVES: Maxwell equations, electromagnetic waves equation and their properties, electromagnetic spectrum.
WAVE REFLECTION AND REFRACTION: mechanical and electromagnetic waves
WAVE INTERFERENCE: Young experiment, olography
WAVE DIFFRACTION: Fraunhofer diffraction, diffraction minima, central maximum width, diffraction from a circular aperture, Airy disk and Rayleigh criterion, resolving power of lenses.
GEOMETRICAL OPTICS: lenses and mirrors, optical instruments, the eye.


ATOMIC AND NUCLEAR PHYSICS

INTRODUCTION TO MODERN PHYSICS:
discovery of the electron, X-rays and radioactivity; black-body radiation and photoelectronic effect; Compton effect; atomic spectra; Rutherford experiment, atomic nucleus, the proton, Bohr’s atom; wavelike behaviour of matter, De Broglie waves, Schroedinger equation, probability waves, X-rays and electronic waves diffraction; magnetic moment and precession motion; orbital and intrinsic magnetic moment of atomic electrons, Stern-Gerlach experiment; atomic structure and periodic table; magnetic moment and spin of the proton; Dirac equation, positrons and anti-matter.

THE ATOMIC NUCLEUS:
Chadwick and the neutron, atomic nucleus properties, mass-energy equivalence, mass defect and bond energy, saturation property of the nuclear force, nuclear shell model, spin of the nucleus, magnetic moment and nuclear magnetic resonance.

RADIOACTIVITY
radioactive decay, natural and artificial nuclides, law of radioactive decay, average life-time and half-life, nuclides for medical imaging.

INTERACTION OF PHOTONS WITH ATOMIC ELECTRONS
photoelectric absorption, Rayleigh and Compton scattering, pair creation, attenuation of a collimated beam, linear attenuation coefficient and atomic cross section.

RADIOPROTECTION
Interaction of charged particles with matter, dosimetry basic concepts: Gray and Sievert, stochastic and non stochastic effects.

IMAGING TECHNIQUES:
optical and electronic microscopy; ultrasonic imaging; X-ray imaging: conventional radiography and TAC, gamma imaging: SPECT, PET; nuclear magnetic resonance imaging (MRI).

Oral exam starting from the presentation, at choice of the student, of one of the imaging techniques object of the course.