* absorbed dose *

Electromagnetic radiation In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. It includes radio waves, microwaves, infrared, (visible) li ...

equivalent dose Equivalent dose is a dose quantity '' H '' representing the stochastic health effects of low levels of ionizing radiation on the human body which represents the probability of radiation-induced cancer and genetic damage. It is derived from the p ...

hormesis Hormesis is a characteristic of many biological processes, namely a biphasic or triphasic response to exposure to increasing amounts of a substance or condition. Within the hormetic zone, the biological response to low exposures to toxins and othe ...

* Ionizing radiation * Louis Harold Gray (British physicist) *

rad (unit) The rad is a unit of absorbed radiation dose, defined as 1 rad = 0.01 Gy = 0.01 J/kg. It was originally defined in CGS units in 1953 as the dose causing 100 ergs of energy to be absorbed by one gram of matter. The material absorbing the radiat ...

radar Radar is a detection system that uses radio waves to determine the distance ('' ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, we ...

radar astronomy Radar astronomy is a technique of observing nearby astronomical objects by reflecting radio waves or microwaves off target objects and analyzing their reflections. Radar astronomy differs from '' radio astronomy'' in that the latter is a passiv ...

radar cross section Radar cross-section (RCS), also called radar signature, is a measure of how detectable an object is by radar. A larger RCS indicates that an object is more easily detected. An object reflects a limited amount of radar energy back to the source. ...

radar detector A radar detector is an electronic device used by motorists to detect if their speed is being monitored by police or law enforcement using a radar gun. Most radar detectors are used so the driver can reduce the car's speed before being ticketed ...

radar gun A radar speed gun (also radar gun and speed trap gun) is a device used to measure the speed of moving objects. It is used in law-enforcement to measure the speed of moving vehicles and is often used in professional spectator sport, for things su ...

radar jamming Radar jamming and deception is a form of electronic countermeasures that intentionally sends out radio frequency signals to interfere with the operation of radar by saturating its receiver with noise or false information. Concepts that blanket the ...

* (radar reflector) corner reflector *

radar warning receiver Radar warning receiver (RWR) systems detect the radio emissions of radar systems. Their primary purpose is to issue a warning when a radar signal that might be a threat is detected, like a fighter aircraft's fire control radar. The warning can t ...

* (Radarange)

microwave oven A microwave oven (commonly referred to as a microwave) is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. This induces polar molecules in the food to rotate and produce ...

radiance In radiometry, radiance is the radiant flux emitted, reflected, transmitted or received by a given surface, per unit solid angle per unit projected area. Radiance is used to characterize diffuse emission and reflection of electromagnetic radiati ...

* (radiant: see) meteor shower * radiation * Radiation absorption * Radiation acne * Radiation angle *

radiant barrier A radiant barrier is a type of building material that reflects thermal radiation and reduces heat transfer. Because thermal energy is also transferred by conduction and convection, in addition radiation, radiant barriers are often supplemented wit ...

* (radiation belt: see) Van Allen radiation belt * Radiation belt electron * Radiation belt model * Radiation Belt Storm Probes * radiation budget *

Radiation burn A radiation burn is a damage to the skin or other biological tissue and organs as an effect of radiation. The radiation types of greatest concern are thermal radiation, radio frequency energy, ultraviolet light and ionizing radiation. The most ...

* Radiation cancer * (radiation contamination)

radioactive contamination Radioactive contamination, also called radiological pollution, is the deposition of, or presence of radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is unintended or undesirab ...

* Radiation contingency *

Radiation damage Radiation damage is the effect of ionizing radiation on physical objects including non-living structural materials. It can be either detrimental or beneficial for materials. Radiobiology is the study of the action of ionizing radiation on livin ...

Radiation damping Radiation damping in accelerator physics is a way of reducing the beam emittance of a high-velocity charged particle beam by synchrotron radiation. The two main ways of using radiation damping to reduce the emittance of a particle beam are the us ...

* Radiation-dominated era *

Radiation dose reconstruction Radiation dose reconstruction refers to the process of estimating radiation doses that were received by individuals or populations in the past as a result of particular exposure situations of concern.''A Review of the Dose Reconstruction Program of ...

* Radiation dosimeter * Radiation effect *

radiant energy Radiant may refer to: Computers, software, and video games * Radiant (software), a content management system * GtkRadiant, a level editor created by id Software for their games * Radiant AI, a technology developed by Bethesda Softworks for '' ...

Radiation enteropathy Radiation enteropathy is a syndrome that may develop following abdominal or pelvic radiation therapy for cancer. Many affected people are cancer survivors who had treatment for cervical cancer or prostate cancer; it has also been termed pelvic r ...

* (radiation exposure)

* Radiation flux * (radiation gauge: see)

gauge fixing In the physics of gauge theories, gauge fixing (also called choosing a gauge) denotes a mathematical procedure for coping with redundant degrees of freedom in field variables. By definition, a gauge theory represents each physically distinct c ...

radiation hardening Radiation hardening is the process of making electronic components and circuits resistant to damage or malfunction caused by high levels of ionizing radiation ( particle radiation and high-energy electromagnetic radiation), especially for environ ...

* (radiant heat)

thermal radiation Thermal radiation is electromagnetic radiation generated by the thermal motion of particles in matter. Thermal radiation is generated when heat from the movement of charges in the material (electrons and protons in common forms of matter) i ...

radiant heating Radiant heating and cooling is a category of HVAC technologies that exchange heat by both convection and radiation with the environments they are designed to heat or cool. There are many subcategories of radiant heating and cooling, including: ...

radiant intensity In radiometry, radiant intensity is the radiant flux emitted, reflected, transmitted or received, per unit solid angle, and spectral intensity is the radiant intensity per unit frequency or wavelength, depending on whether the spectrum is taken ...

radiation hormesis Radiation hormesis is the hypothesis that low doses of ionizing radiation (within the region of and just above natural background levels) are beneficial, stimulating the activation of repair mechanisms that protect against disease, that are not ...

* radiation impedance *

radiation implosion Radiation implosion is the compression of a target by the use of high levels of electromagnetic radiation. The major use for this technology is in fusion bombs and inertial confinement fusion research. History Radiation implosion was first deve ...

Radiation-induced lung injury Radiation-induced lung injury (RILI) is a general term for damage to the lungs as a result of exposure to ionizing radiation. In general terms, such damage is divided into early inflammatory damage (''radiation pneumonitis'') and later complicatio ...

Radiation Laboratory The Radiation Laboratory, commonly called the Rad Lab, was a microwave and radar research laboratory located at the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts. It was first created in October 1940 and operated until 31 ...

radiation length In physics, the radiation length is a characteristic of a material, related to the energy loss of high energy particles electromagnetically interacting with it. Definition In materials of high atomic number (e.g. W, U, Pu) the electrons of energie ...

* radiation mode *

radiation oncologist A radiation oncologist is a specialist physician who uses ionizing radiation (such as megavoltage X-rays or radionuclides) in the treatment of cancer. Radiation oncology is one of the three primary specialties, the other two being surgical and ...

radiation pattern In the field of antenna design the term radiation pattern (or antenna pattern or far-field pattern) refers to the ''directional'' (angular) dependence of the strength of the radio waves from the antenna or other source.Constantine A. Balanis: “A ...

* radiation poisoning (radiation sickness) *

radiation pressure Radiation pressure is the mechanical pressure exerted upon any surface due to the exchange of momentum between the object and the electromagnetic field. This includes the momentum of light or electromagnetic radiation of any wavelength that is a ...

radiation protection Radiation protection, also known as radiological protection, is defined by the International Atomic Energy Agency (IAEA) as "The protection of people from harmful effects of exposure to ionizing radiation, and the means for achieving this". Expos ...

(radiation shield) (radiation shielding) * radiation resistance * Radiation Safety Officer * radiation scattering * radiation therapist *

radiation therapy Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is a therapy using ionizing radiation, generally provided as part of cancer treatment to control or kill malignant cells and normally delivered by a linear accelerator. Radi ...

(radiotherapy) * (radiation treatment)

* (radiation units: see) :Units of radiation dose * (radiation weight factor: see)

radiation zone A radiation zone, or radiative region is a layer of a star's interior where energy is primarily transported toward the exterior by means of radiative diffusion and thermal conduction, rather than by convection. Energy travels through the radiatio ...

radiative cooling In the study of heat transfer, radiative cooling is the process by which a body loses heat by thermal radiation. As Planck's law describes, every physical body spontaneously and continuously emits electromagnetic radiation. Radiative cooling ...

radiative forcing Radiative forcing (or climate forcing) is the change in energy flux in the atmosphere caused by natural or anthropogenic factors of climate change as measured by watts / metre2. It is a scientific concept used to quantify and compare the extern ...

* radiator *

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmi ...

* (radio amateur: see) amateur radio * (radio antenna)

antenna (radio) In radio engineering, an antenna or aerial is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver (radio), receiver. In Transmission (telecommunicati ...

radio astronomy Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation comin ...

* radio beacon * (radio broadcasting: see)

broadcasting Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum ( radio waves), in a one-to-many model. Broadcasting beg ...

* radio clock * (radio communications)

* radio control *

radio controlled airplane A radio-controlled aircraft (often called RC aircraft or RC plane) is a small flying machine that is controlled remotely by an operator on the ground using a hand-held radio transmitter. The transmitter continuously communicates with a receiver ( ...

radio controlled car 'Radio-controlled cars'' (or RC cars for short) are miniature model cars, vans, buses, trucks or buggies that can be controlled from a distance using a specialized transmitter or remote. The term "RC" has been used to mean both "remote controll ...

radio-controlled helicopter A radio-controlled helicopter (also '' RC helicopter'') is model aircraft which is distinct from a RC airplane because of the differences in construction, aerodynamics, and flight training. Several basic designs of RC helicopters exist, of w ...

* radio controlled model * (radio controlled plane)

model aircraft A model aircraft is a small unmanned aircraft. Many are replicas of real aircraft. Model aircraft are divided into two basic groups: flying and non-flying. Non-flying models are also termed static, display, or shelf models. Aircraft manufactur ...

(see under Powered models) * (radio crystal oscillator)

crystal oscillator A crystal oscillator is an electronic oscillator circuit that uses a piezoelectric crystal as a frequency-selective element. The oscillator frequency is often used to keep track of time, as in quartz wristwatches, to provide a stable clock ...

* (radio detection and ranging)

* radio direction finder (RDF) *

radio electronics Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmit ...

Radio Emergency Associated Communication Teams REACT (Radio Emergency Associated Communication Teams) began as a CB radio Emergency Channel 9 monitoring organization across the United States and Canada in 1962. Initially, the primary role of REACT volunteers was to monitor Channel 9, the CB Em ...

* radio equipment *

radio fingerprinting Radio fingerprinting is a process that identifies a cellular phone or any other radio transmitter by the "fingerprint" that characterizes its signal transmission and is hard to imitate. An electronic fingerprint makes it possible to identify a wire ...

radio fix In telecommunication and position fixing, the term radio fix has the following meanings: *The locating of a radio transmitter by bearings taken from two or more direction finding stations, the site of the transmitter being at the point of intersec ...

radio frequency Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the ...

(RF) *

radio frequency engineering Radio-frequency (RF) engineering is a subset of electronic engineering involving the application of transmission line, waveguide, antenna and electromagnetic field principles to the design and application of devices that produce or use signals w ...

radio frequency interference Electromagnetic interference (EMI), also called radio-frequency interference (RFI) when in the radio frequency spectrum, is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrost ...

(RFI) * (radio galaxy: see)

active galaxy An active galactic nucleus (AGN) is a compact region at the center of a galaxy that has a much-higher-than-normal luminosity over at least some portion of the electromagnetic spectrum with characteristics indicating that the luminosity is not prod ...

* (radio ham: see) amateur radio * (radio history)

history of radio The early history of radio is the history of technology that produces and uses radio instruments that use radio waves. Within the timeline of radio, many people contributed theory and inventions in what became radio. Radio development began a ...

radio horizon Line-of-sight propagation is a characteristic of electromagnetic radiation or acoustic wave propagation which means waves travel in a direct path from the source to the receiver. Electromagnetic transmission includes light emissions traveling ...

* radio identification tag * radio jamming * radio masts and towers * (radio mesh network)

wireless mesh network A wireless mesh network (WMN) is a communications network made up of radio nodes organized in a mesh topology. It can also be a form of wireless ad hoc network. Chai Keong Toh Ad Hoc Mobile Wireless Networks, Prentice Hall Publishers, 2002. ...

radio navigation Radio navigation or radionavigation is the application of radio frequencies to determine a position of an object on the Earth, either the vessel or an obstruction. Like radiolocation, it is a type of radiodetermination. The basic principles a ...

radio noise source A radio noise source is a device that emits radio waves at a certain frequency, used to calibrate radio telescopes such that received data may be compared to a known value, as well as to find the focal point of a telescope soon after construction, ...

radio propagation Radio propagation is the behavior of radio waves as they travel, or are propagated, from one point to another in vacuum, or into various parts of the atmosphere. As a form of electromagnetic radiation, like light waves, radio waves are affect ...

* (radio pulsar: see)

rotation-powered pulsar A pulsar (from ''pulsating radio source'') is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation out of its magnetic poles. This radiation can be observed only when a beam of emission is pointing toward Ea ...

* (radio receiver) receiver (radio) * (radio relay link: see) microwave radio relay * (radio scanner) scanner (radio) * radio source * radio source SHGb02 plus 14a * (radio spectrum: see)

radio spectrum pollution Radio spectrum pollution is the straying of waves in the radio and electromagnetic spectrums outside their allocations that cause problems for some activities. It is of particular concern to radio astronomers. Radio spectrum pollution is mitiga ...

radio star Stellar radio sources, radio source stars or radio stars are stellar objects that produce copious emissions of various radio frequencies, whether constant or pulsed. Radio emissions from stars can be produced in many varied ways. Neutron stars P ...

radio station Radio broadcasting is transmission of audio (sound), sometimes with related metadata, by radio waves to radio receivers belonging to a public audience. In terrestrial radio broadcasting the radio waves are broadcast by a land-based radi ...

Radio Technical Commission for Aeronautics RTCA, Inc. (formerly known as Radio Technical Commission for Aeronautics) is a United States non-profit organization that develops technical guidance for use by government regulatory authorities and by industry. It was founded in 1935 and was re-in ...

(RTCA) * (radio telegraphy)

wireless telegraphy Wireless telegraphy or radiotelegraphy is transmission of text messages by radio waves, analogous to electrical telegraphy using cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimental technologies for ...

* (radio telephone) radiotelephone * radio telescope *

radioteletype Radioteletype (RTTY) is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations connected by radio rather than a wired link. Radioteletype evolved from earlier landline teleprinter ...

(RTTY) * (radio tower: see) radio masts and towers * (radio translator)

broadcast translator A broadcast relay station, also known as a satellite station, relay transmitter, broadcast translator (U.S.), re-broadcaster (Canada), repeater (two-way radio) or complementary station (Mexico), is a broadcast transmitter which repeats (or tran ...

* (radio transmission)

transmission (telecommunications) In telecommunications, transmission is the process of sending or propagating an analog or digital signal via a medium that is wired, wireless, or fiber-optic. Transmission technologies typically refer to physical layer protocol duties su ...

* (radio transmitter: see)

transmitter In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the ...

* (radio tube triode: see)

vacuum tube A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied. The type known as ...

(thermionic valve) * (radio tuner)

tuner (radio) A tuner is a subsystem that receives radio frequency (RF) transmissions, such as FM broadcasting, and converts the selected carrier frequency and its associated bandwidth into a fixed frequency that is suitable for further processing, usually b ...

* (radio wave: see)

(RF) *

radio window The radio window is a range of frequencies of electromagnetic radiation that penetrate the earth's atmosphere. It plays an important role in astronomy; up until World War II, astronomers could only use the visible and near infrared portions of the ...

radio-frequency induction : ''For the common use of RF induction process of heating a metal object by electromagnetic induction, see induction heating'' Radio-frequency induction or RF induction is the use of a radio frequency magnetic field to transfer energy by means of e ...

* (radio-jet X-ray binary: see)

microquasar A microquasar, the smaller version of a quasar, is a compact region surrounding a stellar black hole with a mass several times that of its companion star. The matter being pulled from the companion star forms an accretion disk around the black hole ...

* (radio-to-radio: see)

repeater In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Som ...

* (radioactive boy scout)

David Hahn David Charles Hahn (October 30, 1976 – September 27, 2016), sometimes called the "Radioactive Boy Scout" or the "Nuclear Boy Scout", was an American nuclear radiation enthusiast who built a homemade neutron source at the age of seventeen. A ...

* (radioactive cloud: see)

nuclear fallout Nuclear fallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and the shock wave has passed. It commonly refers to the radioac ...

(radioactive exposure) * (radioactive dating)

radiometric dating Radiometric dating, radioactive dating or radioisotope dating is a technique which is used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed. The method compares ...

* radioactive decay * radioactive decay path * (radioactive dust: see)

* (radioactive exposure)

* Radioactive Incident Monitoring Network (RIMNET) (in the UK) * (radioactive isotope) radionuclide *

radioactive quackery Radioactive quackery is quackery that improperly promotes radioactivity as a therapy for illnesses. Unlike radiotherapy, which is the scientifically sound use of radiation for the destruction of cells (usually cancer cells), quackery pseudo-s ...

* (radioactive radiation: see) radiation *

radioactive tracer A radioactive tracer, radiotracer, or radioactive label is a chemical compound in which one or more atoms have been replaced by a radionuclide so by virtue of its radioactive decay it can be used to explore the mechanism of chemical reactions by ...

radioactive waste Radioactive waste is a type of hazardous waste that contains radioactive material. Radioactive waste is a result of many activities, including nuclear medicine, nuclear research, nuclear power generation, rare-earth mining, and nuclear weapons r ...

* (radioactivity) radioactive decay * (radioastronomy)

radiobiology Radiobiology (also known as radiation biology, and uncommonly as actinobiology) is a field of clinical and basic medical sciences that involves the study of the action of ionizing radiation on living things, especially health effects of radiation. ...

* (radiocarbon) carbon-14 * radiocarbon dating (radiocarbon test) * radiocarbon revolution *

radiocarbon year Radiocarbon dating measurements produce ages in "radiocarbon years", which must be converted to calendar ages by a process called calibration. Calibration is needed because the atmospheric / ratio, which is a key element in calculating radiocarbo ...

radiochemistry Radiochemistry is the chemistry of radioactive materials, where radioactive isotopes of elements are used to study the properties and chemical reactions of non-radioactive isotopes (often within radiochemistry the absence of radioactivity leads t ...

* (radiocommunication: see)

* Radiocommunications Agency *

radiocontrast Radiocontrast agents are substances used to enhance the visibility of internal structures in X-ray-based imaging techniques such as computed tomography ( contrast CT), projectional radiography, and fluoroscopy. Radiocontrast agents are typically i ...

radiodensity Radiodensity (or radiopacity) is opacity to the radio wave and X-ray portion of the electromagnetic spectrum: that is, the relative inability of those kinds of electromagnetic radiation to pass through a particular material. Radiolucency or hypod ...

radiodetermination As defined by FS-1037C and ITU Radio Regulations, radiodeterminationITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.9, definition: ''radiodetermination'' is: "the determination of the position, velocity or other chara ...

radiofax Radiofacsimile, radiofax or HF fax is an analogue mode for transmitting monochrome images via high frequency (HF) radio waves. It was the predecessor to slow-scan television (SSTV). It was the primary method of sending photographs from remote s ...

(HF Fax) * (radiofluorescence)

radioluminescence Radioluminescence is the phenomenon by which light is produced in a material by bombardment with ionizing radiation such as alpha particles, beta particles, or gamma rays. Radioluminescence is used as a low level light source for night illumi ...

* (radiofrequency)

radiogenic A radiogenic nuclide is a nuclide that is produced by a process of radioactive decay. It may itself be radioactive (a radionuclide) or stable (a stable nuclide). Radiogenic nuclides (more commonly referred to as radiogenic isotopes) form some ...

radiographer Radiographers, also known as radiologic technologists, diagnostic radiographers and medical radiation technologists are healthcare professionals who specialize in the imaging of human anatomy for the diagnosis and treatment of pathology. Radi ...

* radiohalo *

radioimmunoassay A radioimmunoassay (RIA) is an immunoassay that uses radiolabeled molecules in a stepwise formation of immune complexes. A RIA is a very sensitive in vitro assay technique used to measure concentrations of substances, usually measuring antigen conc ...

* (radioiodine)

iodine-131 Iodine-131 (131I, I-131) is an important radioisotope of iodine discovered by Glenn Seaborg and John Livingood in 1938 at the University of California, Berkeley. It has a radioactive decay half-life of about eight days. It is associated with nu ...

* (radioisotope) radionuclide *

radioisotope thermoelectric generator A radioisotope thermoelectric generator (RTG, RITEG), sometimes referred to as a radioisotope power system (RPS), is a type of nuclear battery that uses an array of thermocouples to convert the heat released by the decay of a suitable radioacti ...

(RTG) * radioisotope heater units * radioisotope rocket * radioisotopic labelling *

radioligand A radioligand is a radioactive biochemical substance (in particular, a ligand (biochemistry), ligand that is radioactive tracer, radiolabeled) that is used for diagnosis or for research-oriented study of the receptor (biochemistry), receptor system ...

* radiolocation * Radiological and Environmental Sciences Laboratory * (radiological bomb)

radiological weapon Radiological warfare is any form of warfare involving deliberate radiation poisoning or contamination of an area with radiological sources. Radiological weapons are normally classified as weapons of mass destruction (WMDs), although radiologica ...

* (radiological dispersal device)

dirty bomb A dirty bomb or radiological dispersal device is a radiological weapon that combines radioactive material with conventional explosives. The purpose of the weapon is to contaminate the area around the dispersal agent/conventional explosion with ...

* (Radiological Dispersion Device)

Radiological Protection Institute of Ireland The Radiological Protection Institute of Ireland (RPII), ''An Institiúid Éireannach um Chosaint Raideolaíoch'', was an independent public body in Ireland under the aegis of the Department of Communications, Climate Action and Environment. The ...

(RPII) *

Radiological Society of North America The Radiological Society of North America (RSNA) is a non-profit organization and an international society of radiologists, medical physicists and other medical imaging professionals representing 31 radiologic subspecialties from 145 countries a ...

radiological warfare Radiological warfare is any form of warfare involving deliberate radiation poisoning or contamination of an area with radiological sources. Radiological weapons are normally classified as weapons of mass destruction (WMDs), although radiologic ...

(radiological dispersion device DD *

radiology Radiology ( ) is the medical discipline that uses medical imaging to diagnose diseases and guide their treatment, within the bodies of humans and other animals. It began with radiography (which is why its name has a root referring to radiat ...

Radiology Information System A radiological information system (RIS) is the core system for the electronic management of imaging departments. The major functions of the RIS can include patient scheduling, resource management, examination performance tracking, reporting, result ...

(RIS) * (radiolucent: see)

(radiofluorescence) * radiolyse * radiometer * (radiometric: see) radiometry *

* radiometry * (radionavigation)

* radionuclide * (radionuclide computed tomography) single-photon emission computed tomography (SPECT) * (radionuclide test: see)

nuclear medicine Nuclear medicine or nucleology is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear imaging, in a sense, is " radiology done inside out" because it records radiation emi ...

radiopharmaceutical Radiopharmaceuticals, or medicinal radiocompounds, are a group of pharmaceutical drugs containing radioactive isotopes. Radiopharmaceuticals can be used as diagnostic and therapeutic agents. Radiopharmaceuticals emit radiation themselves, which ...

radioresistant Radioresistance is the level of ionizing radiation that organisms are able to withstand. Ionizing-radiation-resistant organisms (IRRO) were defined as organisms for which the dose of acute ionizing radiation (IR) required to achieve 90% reducti ...

radiosensitivity Radiosensitivity is the relative susceptibility of cells, tissues, organs or organisms to the harmful effect of ionizing radiation. Cells types affected Cells are least sensitive when in the S phase, then the G1 phase, then the G2 phase, and ...

* radiosity *

radiosonde A radiosonde is a battery-powered telemetry instrument carried into the atmosphere usually by a weather balloon that measures various atmospheric parameters and transmits them by radio to a ground receiver. Modern radiosondes measure or calcula ...

* (radiostation)

* radiosurgery * (radiotelegraphy)

telegraphy Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas ...

* radiotelephone * (radiotelescope) radio telescope *

(RTTY) * (radiotherapy)

* (radiothermal generator)

radioisotope thermal generator A radioisotope thermoelectric generator (RTG, RITEG), sometimes referred to as a radioisotope power system (RPS), is a type of nuclear battery that uses an array of thermocouples to convert the heat released by the decay of a suitable radioacti ...

* (radiotoxic: see) ionizing radiation *

radium Radium is a chemical element with the symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is silvery-white, but it readily reacts with nitrogen (rathe ...

Radium, Colorado Radium, elevation , is a small rural unincorporated community in southwestern Grand County, Colorado, United States. The community sits in the mountains along an isolated stretch of Colorado River downstream from Gore Canyon and southwest of K ...

radium chloride Radium chloride (RaCl2) is a salt of radium and chlorine, and the first radium compound isolated in a pure state. Marie Curie and André-Louis Debierne used it in their original separation of radium from barium. The first preparation of radium me ...

* Radium Girls *

Radium Hot Springs, British Columbia Radium Hot Springs, informally and commonly called Radium, is a village of 1,339 residents situated in the East Kootenay region of British Columbia. The village is named for the hot springs located in the nearby Kootenay National Park. From Banff ...

radon Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colourless, odourless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through ...

radon difluoride Radon difluoride () is a compound of radon, a radioactive noble gas. Radon reacts readily with fluorine to form a solid compound, but this decomposes on attempted vaporization and its exact composition is uncertain. Calculations suggest that it ...

(see same for "radon fluoride") *

relative biological effectiveness In radiobiology, the relative biological effectiveness (often abbreviated as RBE) is the ratio of biological effectiveness of one type of ionizing radiation relative to another, given the same amount of absorbed energy. The RBE is an empirica ...

(RBE) * Röntgen (unit) (roentgen) (symbol R) *

röntgen equivalent man The roentgen equivalent man (rem) is a CGS unit of equivalent dose, effective dose, and committed dose, which are dose measures used to estimate potential health effects of low levels of ionizing radiation on the human body. Quantities measur ...

(rem) *

sievert The sievert (symbol: SvNot be confused with the sverdrup or the svedberg, two non-SI units that sometimes use the same symbol.) is a unit in the International System of Units (SI) intended to represent the stochastic health risk of ionizing rad ...

(symbol: Sv) (unit of dose equivalent)

See also