The becquerel (English: /bɛkəˈrɛl/; symbol: Bq) is the unit of radioactivity in the International System of Units (SI). One becquerel is defined as the activity of a quantity of radioactive material in which one nucleus decays per second. For applications relating to human health this is a small quantity, and SI multiples of the unit are commonly used.
The gray (Gy) and the becquerel (Bq) were introduced in 1975. Between 1953 and 1975, absorbed dose was often measured in rads. Decay activity was measured in curies before 1946 and often in rutherfords between 1946 and 1975.
Like any SI unit, Bq can be prefixed; commonly used multiples are kBq (kilobecquerel, 103 Bq), MBq (megabecquerel, 106 Bq, equivalent to 1 rutherford), GBq (gigabecquerel, 109 Bq), TBq (terabecquerel, 1012 Bq), and PBq (petabecquerel, 1015 Bq). Large prefixes are common for practical uses of the unit.
The global inventory of carbon-14 is estimated to be 8.51018 Bq (8.5 EBq, 8.5 exabecquerel). The nuclear explosion in Hiroshima (an explosion of 16 kt or 67 TJ) is estimated to have injected 81024 Bq (8 YBq, 8 yottabecquerel) of radioactive fission products into the atmosphere.
In 1889, Becquerel became a member of the Académie des Sciences. In 1900, Becquerel won the Rumford Medal for his discovery of the radioactivity of uranium and he was made an Officer of the Legion of Honour. The Berlin-Brandenburg Academy of Sciences and Humanities awarded him the Helmholtz Medal in 1901. In 1902, he was elected as a member of the American Philosophical Society. In 1903, Henri shared a Nobel Prize in Physics with Pierre Curie and Marie Curie for the discovery of spontaneous radioactivity. In 1905, he was awarded the Barnard Medal by the U.S. National Academy of Sciences. In 1906, Henri was elected Vice Chairman of the academy, and in 1908, the year of his death, Becquerel was elected Permanent Secretary of the Académie des Sciences. During his lifetime, Becquerel was honored with membership into the Accademia dei Lincei and the Royal Academy of Berlin. Becquerel was elected a Foreign Member of the Royal Society (ForMemRS) in 1908. Becquerel has been honored with being the namesake of many different scientific discoveries. The SI unit for radioactivity, the becquerel (Bq), is named after him.
There is a crater named Becquerel on the Moon and also a crater named Becquerel on Mars. The uranium-based mineral becquerelite was named after Henri.Minor planet 6914 Becquerel is named in his honor.
The becquerel or Bq is the SI unit for radioactive decay, measuring the activity of a substance, and is defined as one nucleus decaying per second (units of s-1). The becquerel is named after French physicist Henri Becquerel, who is known for his work with light, and shared the Nobel prize in 1903 with Pierre and Marie Curie for the discovery of natural radiation.
The becquerel is a very small unit of activity in general applications, so for practical reasons it is commonly prefixed as kilobecquerels (103 Bq), megabecquerels (106 Bq), gigabecquerels (109 Bq) or even terabecquerels (1012 Bq).
"Becquerel" and "sievert" are the most common units of radiation. Becquerel is a unit of radioactivity and focuses on where radiation comes from. It is used to express the amount of radioactive materials contained in soil, foods, tap water, etc. The higher the value expressed in becquerels, the larger the radiation being emitted. Sievert is a unit of radiation exposure dose that a person receives and is used with regard to what is exposed to radiation, i.e. the human body. The larger the value expressed in sieverts, the larger the effects of radiation to which the human body is exposed (p.40 of Vol. 1, "Concepts of Doses: Physical Quantities, Protection Quantities and Operational Quantities").
A becquerel (shorthand: Bq, named after French physicist Henri Becquerel) is the International Standard unit of measurement for radioactive decay. Becquerel is also the last name of the man who discovered radioactivity itself, using Uranium, a possible reference to Jade's Associated Item. Continuing the physics theme, abbreviating his name to Bec might also allude to Bose-Einstein condensate.
A material's radioactivity is measured in becquerels (Bq, international unit) and curies (Ci, U.S. unit). Because a curie is a large unit, radioactivity results are usually shown in picocuries (pCi). A picocurie is one trillionth of a curie. The higher the number, the more radiation released by the material.
The discovery of spontaneous radioactivity spread rapidly and engendereda flurry of new research on the phenomenon, much of it by Marie andPierre Curie. Becquerel also continued to study the phenomenon: In 1899,he discovered that X-rays could be deflected by a magnetic field,suggesting that the radiation contained electrically charged particles.The international unit of radioactivity, the becquerel (defined as onenucleus decay per second), was named for him. But Becquerel was stillfascinated by the interaction between crystals and light, and heeventually returned to this research, studying how crystals absorb andpolarize light.
The becquerel (symbol: Bq) is the SI unit of radioactivity and is defined as one nuclear disintegration per second 1; it officially replaced the curie (Ci), the unit in the superseded cgs system, in 1975.
On Radiopaedia.org we primarily express all radioactive doses in becquerels. However as the curie remains in common use in some parts of the world we always provide the curie equivalent in brackets after the becquerel dose, e.g. 37 MBq (1 mCi)
The unit was proposed in 1975 by the International Commission on Radiation Units and Measurements (ICRU). It is named after Antoine Henri Becquerel, the French physicist, who discovered radioactivity, and shared the Nobel Prize for Physics in 1903 with Marie Skłodowska-Curie and her husband Pierre Curie 1,2. Ironically the former unit that the becquerel replaced was the curie!
(English pronunciations of becquerel from the Cambridge Advanced Learner's Dictionary & Thesaurus and from the Cambridge Academic Content Dictionary, both sources Cambridge University Press)
The word 'amount' is in quotes as the becquerel is really a rate rather than a specific quantity. For a further study of this statement you need to consider specific activity which we will deal with in other resource.
This unit was defined in 1910, before the becquerel (Bq) was adopted by the SI system. History shows that the unit was formally defined as the activity of 1g of radium, however precisely, the curie (Ci) is defined as follows: 041b061a72