| Definition/Meaning | Word/Phrase |
|---|
| metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation |
A
,
angstrom
,
angstrom unit
|
| (physics) material in a nuclear reactor that absorbs radiation |
absorber
|
| measure of the rate of decrease in the intensity of electromagnetic radiation (as light) as it passes through a given substance; the fraction of incident radiant energy absorbed per unit mass or thickness of an absorber |
absorptance
,
absorption coefficient
,
coefficient of absorption
|
| (physics) the property of a body that determines the fraction of the incident radiation or sound flux absorbed or absorbable by the body |
absorption factor
,
absorptivity
|
| spectrum of electromagnetic radiation that has passed through a medium that absorbed radiation of certain wavelengths |
absorption spectrum
|
| electromagnetic radiation that can produce photochemical reactions |
actinic radiation
,
actinic ray
|
| property of radiation that enables it to produce photochemical effects |
actinism
|
| instrument for measuring the intensity of electromagnetic radiation (usually by the photochemical effect) |
actinometer
|
| measuring the intensity of electromagnetic radiation (especially of the sun's rays) |
actinometry
|
| efficiency with which electromagnetic radiation produces a photochemical reaction plotted as a function of the wavelength of the radiation |
action spectrum
|
| acute blood disorder (often caused by radiation or drug therapy) characterized by severe reduction in granulocytes |
agranulocytosis
,
agranulosis
,
granulocytopenia
|
| Russian physicist whose research into ways of moving electrons around atoms led to the development of masers and lasers for producing high-intensity radiation (1916-2002) |
Aleksandr Mikjailovich Prokhorov
,
Aleksandr Prokhorov
,
Prokhorov
|
| radiation of alpha particles during radioactive decay |
alpha radiation
,
alpha ray
|
| agent (as heat or radiation or a chemical) that destroys microorganisms that might carry disease |
antimicrobial
,
antimicrobic
,
disinfectant
,
germicide
|
| any telescope designed to collect and record electromagnetic radiation from cosmic sources |
astronomical telescope
|
| satellite equipped with a telescope to observe infrared radiation |
astronomy satellite
|
| (physics) a spectrum of radiation caused by electron transitions within an atom; the series of spectrum lines is characteristic of the element |
atomic spectrum
|
| luminous radiation |
aura
|
| radiogram produced by radiation emitted by the specimen being photographed |
autoradiograph
|
| producing a radiograph by means of the radiation emitted from the specimen being photographed |
autoradiography
|
