roentgen

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.

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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

/roent·gen/ (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 dry air produces in air ions carrying 1 electrostatic unit of electrical charge of either sign. Symbol R.

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.

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roent′gen adj.

roentgen (R)

[rent′gən, ren′jən]

Etymology: Wilhelm K. Roentgen, German physicist, 1845-1923

the quantity of x-radiation or gamma radiation that creates 1 electrostatic unit of ions in 1 mL of air at 0° and 760 mm of pressure. In radiotherapy or radiodiagnosis, the roentgen is the unit of the emitted dose. See also radiation absorbed dose, rem.

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-ray

roentgenograph - Synonym(s): radiograph

roentgen

a superseded 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. Now replaced by coulomb/kg (C/kg); see coulomb. 1 R = 2.58 × 10⁻⁴ C/kg; 1 C/kg = 3876 R.

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roentgen equivalent man (rem)

see rem.

roentgen equivalent physical (rep)

see rep.

roentgen ray

x-ray.