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ELECTROMAGNETIC RADIATION. PHOTONS ARE ENERGY DISTURBANCES MOVING THROUGH THE SPACE WITH THE SPEED OF LIGHT (c). PHOTONS HAVE NO MASS AND NO CHARGE. THEY HAVE MAGNETIC AND ELECTRIC FIELDS CHANGING IN SINUSOIDAL FASHION. CHARACTERISTICS OF X-RAY PHOTONS.
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PHOTONS ARE ENERGY DISTURBANCES MOVING THROUGH THE SPACE WITH THE SPEED OF LIGHT (c)
PHOTONS HAVE NO MASS AND NO CHARGE. THEY HAVE MAGNETIC AND ELECTRIC FIELDS CHANGING IN SINUSOIDAL FASHION
CHARACTERISTICS OF X-RAY PHOTONS • Highly penetrating, invisible rays, more penetrating than Alpha and Beta radiations. • Electrically neutral. They do not get attracted to charged electrodes. • Polyenergetic. X-ray beam represent the wide range of different photon energies, with the maximum energy photons indicated by the kVp setting. • Release small amounts of thermal energy when they pass through matter. • Travel in straight lines. • Travel with the speed of light in vacuum. • Ionize matter by removing orbital electrons. • Induce fluorescense in some substances. • Can't be focused by lenses nor by collimators. • Produce chemical and biological changes • Produce scatter radiation
Highly penetrating, invisible rays, more penetrating than Alpha and Beta radiations
Electrically neutral. They do not get attracted to charged electrodes
Travel with the speed of light in vacuum. • 3 x 10 8 m/s • 3 x 10 5 km/s • 186,400 miles/sec
XMM-NEWTON SATELLITE UNCOVERS DIFFUSE X-RAY EMISSION AND THE FIRST ACCRETING X-RAY PULSAR IN ANDROMEDA GALAXY
THREE WAVE PARAMETERS ARE NEEDED TO DESCRIBE ELECTROMAGNETIC RADIATION:VELOCITY, WAVELENGTH, AND FREQUENCY
ELECTROMAGNETIC WAVE EQUATION c = f x Λ
Short wavelengthHigh frequencyHigh energy Long wavelengthLow frequencyLow energy
THE ENERGY OF PHOTON IS DIRECTLY PROPORTIONAL TO ITS FREQUENCY
THE ONLY DIFFERENCE BETWEEN X-RAYS AND GAMMA RAYS IS THEIR ORIGIN
VISIBLE LIGHT IS IDENTIFIED BY: • WAVELENGTH
RF IS IDENTIFIED BY: • FREQUENCY
X-RAYS ARE IDENTIFIED BY: • ENERGY
RADIATION ATTENUATION IS THE REDUCTION IN INTENSITY RESULTING FROM SCATTERING AND ABSORPTION
STRUCTURES THAT ABSORB X-RAYS ARE CALLED • RADIOPAQUE ????
STRUCTURES THAT ATTENUATE X-RAYS ARE CALLED RADIOLUCENT ??
Where: I1 = Intensity 1 at D1 I2 = Intensity 2 at D2 Where: D1 = Distance 1 from source I1 = Intensity 1 at D1 D2 = Distance 2 from source I2 = Intensity 2 at D2 D1 = Distance 1 from source D2 = Distance 2 from source