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roentgenenUK
roent·gen also rönt·gen R0283400 (rĕnt′gən, -jən, rŭnt′-)n. Abbr. R or r A unit of radiation exposure equal to the quantity of ionizing radiation that will produce one electrostatic unit of electricity in one cubic centimeter of dry air at 0°C and standard atmospheric pressure.
[After Wilhelm Conrad Roentgen.]
roent′gen adj.Roentgen or Röntgenn (Biography) Wilhelm Konrad (ˈvɪlhɛlm ˈkɔnraːt). 1845–1923, German physicist, who in 1895 discovered X-rays: Nobel prize for physics 1901
roentgen (ˈrɒntɡən; -tjən; ˈrɛnt-) or röntgenn (Units) a unit of dose of electromagnetic radiation equal to the dose that will produce in air a charge of 0.258 × 10–3 coulomb on all ions of one sign, when all the electrons of both signs liberated in a volume of air of mass one kilogram are stopped completely. Symbol: R or r [C20: named after W. K. Roentgen]Roent•gen or Rönt•gen (ˈrɛnt gən, -dʒən, ˈrʌnt-)
n. 1. Wilhelm Konrad, 1845–1923, German physicist. 2. (l.c.) a unit of radiation dosage equal to the amount of ionizing radiation required to produce one electrostatic unit of charge per cubic centimeter of air. Abbr.: r, R roentgenA unit of exposure dose of gamma (or X-) radiation. In field dosimetry, one roentgen is essentially equal to one rad.Thesaurus| Noun | 1. |  roentgen - a unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry airRradioactivity unit - a measure of radioactivity | | 2. |  Roentgen - German physicist who discovered x-rays and developed roentgenography (1845-1923)Rontgen, Wilhelm Konrad Roentgen, Wilhelm Konrad Rontgen |
Translations
RoentgenenUK
roentgen, r?ntgen a unit of dose of electromagnetic radiation equal to the dose that will produce in air a charge of 0.258 × 10--3 coulomb on all ions of one sign, when all the electrons of both signs liberated in a volume of air of mass one kilogram are stopped completely.
Roentgen, R?ntgen Wilhelm Konrad . 1845--1923, German physicist, who in 1895 discovered X-rays: Nobel prize for physics 1901 Roentgen a subsidiary unit of the exposure dose of gamma radiation and X-radiation that is determined by the ionizing effect of gamma radiation and X-radiation on the air. This unit was named in honor of W. K. Roentgen. The international abbreviation for roentgen is R. The quanta of gamma radiation and X-radiation effect the ionization of molecules in the air, which results in the formation of pairs of charged particles, including electrons of significant kinetic energy. These electrons in turn ionize the air. An exposure dose of gamma radiation or X-radiation is equal to 1 R when the corresponding corpuscular radiation (that is, electrons) produces ions whose total charge is equal to one electrostatic unit of the electric charge of each sign in 0.001293 g of air, or in 1 cm3 of air under normal conditions. It is understood here that the charged particles formed in 1 cm3 of air expend all the energy received on ionization. By definition, the roentgen can be used only for radiation having quanta of energy no greater than 3 million electron volts (MeV). A dose of 1 R corresponds to the formation of 2.08 × 109 pairs of ions in 1 cm3 of air or 1.61 × 1012 pairs of ions in 1 g of air. In the International System of Units, the unit of exposure dose is 1 coulomb (C) per kg. According to GOST 8848–63, 1 R = 2.57976 × 10–4 C/kg. The average ionization energy of the molecules in the air is 34 electron volts, 1 R is equivalent to 88 ergs/g. This quantity is called the roentgen equivalent physical (rep). roentgen[′rent·gən] (nucleonics) An exposure dose of x- or γ-radiation such that the electrons and positrons liberated by this radiation produce, in air, when stopped completely, ions carrying positive and negative charges of 2.58 × 10-4 coulomb per kilogram of air. Abbreviated R (formerly r). Also spelled röntgen. roentgenenUK
roentgen [rent´gen] the international unit of x- or γ-radiation; it is the quantity of x- or γ-radiation such that the associated corpuscular emission per 0.001293 g of air produces, in air, ions carrying 1 electrostatic unit of electrical charge of either sign. Abbreviated R.Roent·gen (rĕnt'gĕn), Wilhelm K., German physicist and Nobel laureate, 1845-1923. Discovered x-rays in November, 1895; awarded Nobel Prize in Physics in 1901 for his discovery. See: roentgen, roentgen ray.
roent·gen (R, r), (rĕnt'gĕn, rent'chen), The international unit of exposure dose for x-rays or gamma rays; that quantity of radiation that will produce, in 1 cc or 0.001293 g of air at STP, 2.08 × 109 ions of both signs, each totaling 1 electrostatic unit (esu) of charge; in the MKS system this is 2.58 × 10-4 coulombs per kg of air. [Wilhelm K. Roentgen] roentgen also röntgen (rĕnt′gən, -jən, rŭnt′-)n. Abbr. R or r A unit of radiation exposure equal to the quantity of ionizing radiation that will produce one electrostatic unit of electricity in one cubic centimeter of dry air at 0°C and standard atmospheric pressure.
roent′gen adj.roent·gen (r, R) (rent'gen) The international unit of exposure dose for x-rays or gamma rays; that quantity of radiation that will produce in 1 cm of air at STP, or 0.001293 g of air, 2.08 × 109 ions of both signs, each totaling 1 electrostatic unit (e.s.u.) of charge; in the MKS system this is 2.58 × 10-4 coulombs per kg of air. [Wilhelm K. Roentgen]Roentgen or Röntgen, Wilhelm Konrad (1845–1923) German physicist who discovered X-RAYS. A roentgen or röntgen is the quantity of X-rays or gamma radiation used as a unit of radioactivity. Symbol: R or r.Roentgen, Wilhelm K., German physicist and Nobel laureate, 1845-1923. roentgen - the international unit of exposure dose for x-rays or gamma rays.roentgen ray - Synonym(s): x-rayroentgenograph - Synonym(s): radiographAcronymsSeeRroentgenenUK
Related to roentgen: Roentgen equivalent man, roentgen raySynonyms for roentgennoun a unit of radiation exposureSynonymsRelated Wordsnoun German physicist who discovered x-rays and developed roentgenography (1845-1923)Synonyms- Rontgen
- Wilhelm Konrad Roentgen
- Wilhelm Konrad Rontgen
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