roentgen
Ionizing radiation measure
A roentgen is a unit measuring exposure to ionizing radiation, particularly X-rays and gamma rays.
Named after Wilhelm Röntgen, who discovered X-rays in 1895, the unit quantifies the amount of radiation that produces a specific ionization in air.
Though largely replaced by the coulomb per kilogram in scientific contexts, roentgen remains common in medical and industrial usage: The technician measured 50 roentgens at the site.
Exposure measurement device
Penetrating diagnostic beam
- fluoroscopyContinuous X-ray video imaging
- mammographyBreast cancer screening X-ray
- angiographyImaging of blood vessels
- radiographerMedical imaging professional
detector · barium · screening · diagnostic
Passing into or through
- electromagneticInvolving electric and magnetic fields
- wavelengthSpatial repetition interval
- photonElectromagnetic radiation unit
- radioactiveEmitting nuclear decay particles
shielding · lead · radiobiology · scatter · attenuation · absorption
Year in the 1890s
- fluorescenceLight emitted after absorption
- serendipityAccidental fortunate discovery
- breakthroughSudden important advance
- physicsScience of matter and energy
dosimeter
Exposure measurement device
gray · calibration · threshold
X-ray
Penetrating diagnostic beam
- fluoroscopyContinuous X-ray video imaging
- mammographyBreast cancer screening X-ray
- angiographyImaging of blood vessels
radiographer · detector · barium · screening · diagnostic
penetrating
Passing into or through
- electromagneticInvolving electric and magnetic fields
- wavelengthSpatial repetition interval
- photonElectromagnetic radiation unit
radioactive · shielding · lead · radiobiology · scatter · attenuation · absorption
1895
Year in the 1890s
- fluorescenceLight emitted after absorption
- serendipityAccidental fortunate discovery
- breakthroughSudden important advance
- unitsunit, angstrom, yard, meter, base units
- Nuclearnuclear reactor, atomic bomb, nuclear energy, atomic bombs, uranium
- radiation scienceradioactive decay, ionizing radiation, gamma rays, alpha particles, beta particles
- nuclear radiationradiation exposure, radiation poisoning, radioactive isotopes, fallout, nuclear meltdown
- X-rayschest x-ray, x-ray machine, bone x-ray, dental x-rays, chest x-rays
- radiobiologyradiobiology, DNA damage, mutations, ionizing radiation, cell damage