Chapter 1: Types of Radiation: Characterization and Sources Flashcards
__________ is the transport of energy without the necessary intervention of a transporting medium.
Radiation
Radiation is accomplished by either _________ or by _______ which includes _____, _______, and _______.
electromagnetic waves
particles
electrons
neutrons
ions
Non-ionizing radiation cannot ionize matter and includes _________, ________, ________ and ________.
infrared
lasers
ultrasound
microwaves
Ionizing radiation is divided into _________ and ________.
EM radiation
particulate radiation
Diagnostic imaging methods include __________, __________, ___________, and _________.
x rays
radionuclides
ultrasound
nuclear magnetic resonance imaging
Therapeutic radiology methods include ________, _________, and __________.
radiation oncology/malignant disease
teletherapy
brachytherapy
For __________ the radiation source is outside the subject.
telepathy
The difference between x rays and gamma rays is ___________. X rays are made from ____________ and gamma rays are made from ____________.
how you produce it
electron bombardment
radioactive elements
For UV radiation far UV has wavelength ________ and near UV has wavelength _________.
200-300 nm
300-380 nm
UV A has wavelength __________ and causes ________ damage. UV B has wavelength _________ and UV C has wavelength __________, both cause __________ damage.
315-380 nm
little
280-315 nm
200-280 nm
significant
UV at ________ wavelength does not cause as much damage because DNA _________.
longer
wont absorb
_________ radiation produces greater damage than _______ radiation because of multiple photon absorption, shorter wavelength and higher intensity.
ionizing
heat
Energy in the form of heat/mechanical energy is absorbed _________ and _______, and requires much _________ quantities of energy to produce damage in living things.
uniformly
evenly
greater
x rays deposit energy in tissues and cells in ________ packets called ________.
discrete
photons
Potency of x-rays is a function of ____________ not of __________.
energy of individual photons
total energy of observer
The energy of photons required to break chemical bonds and cause biological tissue damage is __________. The energy required to produce electrons in water is ________.
4-6 eV
7 eV
The emission spectrum of solar radiation from the sun is described as that of a __________ at temperature = ________.
black body
6000 K
mercury gas discharge tubes can be used to ________ and _____________.
generate UV
kill bacteria in water samples
The four types of artificial UV sources are ___________, __________, ________, and __________.
mercury gas discharge tubes
xenon and deuterium discharge tubes
UV lasers
synchrotron radiation
Xenon and deuterium discharge tubes have ____________ and use ________/________ to produce monochromatic radiation in radiation biology.
continuous emission spectrum
monochromators/optical filters
UV lasers are _____________.
powerful monochromatic sources
Synchrotron radiation is produced by _________ and cover a ______ range of energies.
electron accelerators
wide
Ionizing radiation is classified as either _________ or ________ radiation.
electromagnetic
particulate
Ionizing radiation can be produced either from _______________ to react with suitable targets for producing secondary radiations or ____________.
acceleration of charged particles
use of radioactive nuclei
______ are generated when accelerated electrons interact with matter. There are two processes: ________ radiation and _______ radiation.
x rays
characteristic
bremsstrahlung
_________ correspond to the transition of energy gap between atomic orbitals.
characteristic x rays
__________ comes from interaction with nucleus.
Bremsstrahlung radiation
________ are emitted as part of nuclear disintegration. They are made of ________.
gamma rays
photons
x rays have a _______ spectrum whereas gamma rays have _______ energies.
wide energy
well-defined
The most common gamma ray emitters are _______, _______, _______ or ______.
Co-60
Cs 137
I 125
I131
The specific energy emitted from Co-60 is _______.
1.2 MeV
_______ are particles that can be accelerated to high energy to a speed of almost the speed of light using an electrical device such as _______ or _______. This is ______ radiation and has a ________ distribution in tissue. Used for ___________.
electrons
betatron
linear accelerator
beta
non-uniform
cancer therapy
The difference between electrons and protons is ______. Protons are ________ of electrons.
mass
2000x the size
______ are massive and thus require more complex/expensive equipment such as a _______ to accelerate them to useful energies. Used for ________ because of their favorable dose distribution. Have a _______ distribution of energy.
protons
cyclotron
cancer treatment
uniform
_______ from the sun and cosmic rays represent a component of natural background radiation and are the main hazard to astronauts. Humans on earth are protected by earth’s _________ and _________.
photons
atmosphere
magnetic field
_________ are helium nuclei consisting of 2 protons and 2 neutrons, which are produced by radioactive decay. These emissions are accompanied by _______ components which may not be neglected because of their _________. They may also be emitted during _________ of __________ such as _______ and ________.
alpha paticles
gamma components
larger penetration
decay
heavy, naturally occurring radionuclides
uranium
radium
Alpha particles have ________ applications because of __________ resulting in ________. Can be used for _____________.
limited
large size and mass
small range in matter
localize damage in tissue
_____ emits alpha particles that make up a major source of natural background radiation. It increases risk of _________.
radon
lung cancer
________ have similar mass to protons.
neutrons
________ are produced if a charged particle is accelerated to high energy and then made to impinge on suitable target material or through nuclear reactions.
neutrons
Neutrons are present in large quantities in __________ and are emitted by some _________. They are an important component of _________.
nuclear reactors
artificial heavy radionuclides
space radiation
__________ are nuclei of elements such as _____, ______, ______, or _____. Can be accelerated to relativistic energies with very high intensity. Applications in _________. _______ of _______ energy are a ________ to astronauts on long missions.
heavy charged particles
carbon, neon, argon, iron
radiotherapy
Charged particles
enormous
major threat
__________ refers to particles that are emitted from nuclei as a result of nuclear instability.
radioactivity
The half-life of a given nuclear species is related to its _____________.
radiation risk
For a given atom, X is the _________. A (top) is the _______ which is the ____________. Z (bottom) is the ________ which is the __________.
symbol for element
mass number
number of neutrons + protons
atomic number
number of protons in nucleus or number of electrons outside nucleus
Isotopes are nuclei with _________. Isotones are nuclei with __________.
same number of protons
same number of neutrons
The half life is the time for ______________.
50% of the original nuclei disintegrate
Activity is the _________.
rate of decay
Alpha particles have _______ range because of its ___________. The penetration depth of alpha particles is ________. They can be stopped by _________.
shortest
strong interaction with matter
nm to tens of um
tissue
Beta particles have ______ range because of its _________ interaction with matter. The penetration depth is _________. They can pass through ______ but are stopped by _______.
short
strong
um to few mm
tissue
aluminum
Gamma rays are ____________. The penetration depth is _______. They can pass through _______, _______, or _______ but not _______.
extremely penetrating
few cm
tissue, aluminum, concrete
lead
The practical threshold for radiation risk is that of ____________.
ionization of tissue
The ionization energy of a hydrogen atom is _____.
13.6 eV
_______ is the number of nuclear decays per unit time of a radioactive isotope. SI unit: ________, previously _______ which is equal to ________.
activity
becquerel
Curie
1 Ci = 3.7 x 10^10 Bq
__________ is the charge liberated by ionizing radiation per unit mass of air. Unit: ________ which is also equal to ________.
exposure
Roentgen
1 R = 2.58 x 10^-4 C/kg
___________ is the energy absorbed per unit mass of material or energy deposited by ionizing radiation per unit mass of material. Unit: _________ which is ________.
Absorbed dose
Gray
1 Gy = 100 rad = 1 J/kg
________ is absorbed dose x relative biological effectiveness. Unit: _______ which is ________
dose equivalent
Sievert
1 Sv = 100 rem
