A shallow donor refers to a donor that contributes an electron that exhibits energy states equivalent to atomic hydrogen with an altered expected mass i.e. the long range coulomb potential of the ion-cores determines the energy levels.
 Essentially the electron orbits the donor ion within the semiconductor material at approximately the bohr radius.
 This is in contrast to deep level donors where the short range potential determines the energy levels, not the effective mass states.
 This contributes additional energy states that can be used for conduction.
The Bohr radius ("a" or "r") is a physical constant, approximately equal to the most probable distance between the center of a nuclide and the electron in a hydrogen atom in its ground state.
 It is named after Niels Bohr, due to its role in the Bohr model of an atom.
 Its value is .
Since 1901, the Nobel Prize in Literature (Swedish: "Nobelpriset i litteratur" ) has been awarded annually to an author from any country who has, in the words of the will of Alfred Nobel, produced "in the field of literature the most outstanding work in an ideal direction" (original Swedish: "den som inom litteraturen har producerat det mest framstående verket i en idealisk riktning").
 Though individual works are sometimes cited as being particularly noteworthy, here "work" refers to an author's work as a whole.
 The Swedish Academy decides who, if anyone, will receive the prize in any given year.
 The academy announces the name of the chosen laureate in early October.
 It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895; the others are the Nobel Prize in Chemistry, Nobel Prize in Physics, Nobel Peace Prize, and Nobel Prize in Physiology or Medicine.
The Nobel Prize in Physiology or Medicine (Swedish: "Nobelpriset i fysiologi eller medicin" ) is awarded annually by the Swedish Karolinska Institute to scientists and doctors in the various fields of physiology or medicine.
 It is one of the five Nobel Prizes established by the 1895 will of Alfred Nobel (who died in 1896), awarded for outstanding contributions in chemistry, physics, literature, peace, and physiology or medicine.
 As dictated by Nobel's will, the award is administered by the Nobel Foundation and awarded by a committee that consists of five members and an executive secretary elected by the Karolinska Institute.
 While commonly referred to as the Nobel Prize in Medicine, Nobel specifically stated that the prize be awarded for "physiology or medicine" in his will.
 Because of this, the prize can be awarded in a broader range of fields.
 The first Nobel Prize in Physiology or Medicine was awarded in 1901 to Emil Adolf von Behring, of Germany.
 Each recipient receives a medal, a diploma and a monetary award that has varied throughout the years.
 In 1901, von Behring received 150,782 SEK, which is equal to 7,731,004 SEK in December 2008.
 In 2013, the prize was awarded to James E. Rothman, Randy W. Schekman and Thomas C. Südhof; they were recognised "after discovering how cells precisely transport material".
 The award is presented in Stockholm at an annual ceremony on December 10, the anniversary of Nobel's death.
Aage Niels Bohr (] ; 19 June 1922 – 8 September 2009) was a Danish nuclear physicist who shared the Nobel Prize in Physics in 1975 with Ben Mottelson and James Rainwater "for the discovery of the connection between collective motion and particle motion in atomic nuclei and the development of the theory of the structure of the atomic nucleus based on this connection".
 Starting from Rainwater's concept of an irregular-shaped liquid drop model of the nucleus, Bohr and Mottelson developed a detailed theory that was in close agreement with experiments.
 Since his father, Niels Bohr, had won the prize in 1922, he and his father were one of the six pairs of fathers and sons who have both won the Nobel Prize and one of the four pairs who have both won the Nobel Prize in Physics.
Mohammad Abdus Salam {'1': ", '2': ", '3': 'NI, SPk, KBE', '4': "} (Punjabi, Urdu: ‎ ; ] ; 29 January 192621 November 1996), was a Pakistani theoretical physicist.
 A major figure in 20th century theoretical physics, he shared the 1979 Nobel Prize in Physics with Sheldon Glashow and Steven Weinberg for his contribution to the electroweak unification theory.
 He was the first Pakistani and first Muslim to receive a Nobel Prize in science and the second from an Islamic country to receive any Nobel Prize (after Anwar Sadat of Egypt).
The Nobel Prize in Physics (Swedish: "Nobelpriset i fysik" ) is a yearly award given by the Royal Swedish Academy of Sciences for those who conferred the most outstanding contributions for mankind in the field of physics.
 It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others being the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and Nobel Prize in Physiology or Medicine.
Niels Henrik David Bohr (] ; 7 October 1885 – 18 November 1962) was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922.
 Bohr was also a philosopher and a promoter of scientific research.
This is a list of Danish Nobel laureates.
 Since the Nobel Prize was established per the will of Swedish inventor Alfred Nobel in 1895, 12 of the prize winners have been from Denmark.
 The first Danish Nobel laureate was Niels Ryberg Finsen, who won a Nobel Prize for medicine in 1903 for his work in using light therapy to treat diseases.
 The most recent Danish Nobel Prize winner was Jens Skou who won the prize in chemistry for his discovery over the enzyme, Na+/K+-ATPase in 1997.
 To date, of the 13 Nobel Prizes won by Danish people, 5 have been for medicine, 3 have been for physics, 3 have been for literature, 1 has been for chemistry and one has been for peace.
Muonium is an exotic atom made up of an antimuon and an electron, which was discovered in 1960 and is given the chemical symbol .
 During the muon's lifetime, muonium can enter into compounds such as muonium chloride () or sodium muonide ().
 Due to the mass difference between the antimuon and the electron, muonium () is more similar to atomic hydrogen () than positronium ().
 Its Bohr radius and ionization energy are within 0.5% of hydrogen, deuterium, and tritium, and thus it can usefully be considered as an exotic light isotope of hydrogen.

Question: What year did the person who the Bohr radius is named after, receive a Nobel Prize in Physics?
Answer: 1922