INTERACTION OF PARTICULATE RADIATION WITH MATTER Flashcards
(26 cards)
Particles of ionizing radiation include charged
particles, such as — particles, ——,
——-, ——— particles, and ——, and
uncharged particles, such as —–.
alpha particles, protons,
electrons, beta particles, and positrons, and
uncharged particles, such as neutrons
—– charged particles all interact with
matter by electrical forces and lose kinetic
energy via —–, ——-, and
———
energetic, excitation, ionization radiative losses
———– and ——– occur when charged
particles lose energy by interacting with
orbital electrons.
Excitation, ionization
Is the transfer of some of the incident
particle’s energy to electrons in the
absorbing material, promoting them to
electron orbitals farther from the nucleus
(i.e., higher energy levels).
Excitation
The energy transferred to an electron does
—– its binding energy.
does
not exceed
The electron will return to a lower energy
level, with the emission of the excitation
energy in the form of ————-
electromagnetic
radiation or Auger electrons
If the transferred energy exceeds the binding
energy of the electron whereby the electrons
is totally ejected from the atom.
Ionization
The result of ionization is an ——–
consisting of the ejected electron and the
positively charged atom
ion pair
Result from the ejected electrons that have
sufficient energy to produce further
ionizations.
Secondary Ionization
in Secondary Ionization
, the electrons are called? These electrons are called ——–
delta rays.
The number of primary and secondary ion
pairs produced per unit length of the charged
particle’s path is expressed in ——-
ion pairs
(IP)/mm.
Specific ionization —— with the
increases of the particle and
decreases with incident ——.
electrical charge, particle velocity
A ——- produces a greater
coulombic field; as the particle loses energy,
it slows down, allowing the coulombic field to
interact at a given location for a longer period
of time.
larger charge
An alpha particle can have as high as —–
7,000
IP/mm in air.
As the alpha particle slows, the specific
ionization increases to a maximum (called
the ???????).
bragg peak
As the alpha particle decreases rapidly,
alpha particle ??????? and
becomes electrically neutral, thus losing its
capacity for further ionization
picks up electrons
_______ follow tortuous paths in matter as
the result of multiple scattering events
caused by coulombic deflections (repulsion
and/or attraction).
electrons
_______ has a larger mass results in a
dense and usually linear ionization track
alpha particle
——– of a particle is defined as the
actual distance the particle travels
Path length
_______ is defined as the actual
depth of penetration of the particle in matter
Range of a particle
The path length of the electron almost
always __________
exceeds its range
The path length and range of the alpha
particle is being nearly ——–
equal
The amount of energy deposited per unit
path length.
LET
LET is usually expressed in units of
______
eV/cm
