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neutrography

(Encyclopedia)neutrography: see neutron.

supernova

(Encyclopedia)supernova, a massive star in the latter stages of stellar evolution that suddenly contracts and then explodes, increasing its energy output as much as a billionfold. Supernovas are the principal distr...

nucleon

(Encyclopedia)nucleon, term applying to both the proton and the neutron, the two constituents of atomic nuclei. The nucleon may be considered a single particle, of which the proton and the neutron are two different...

black hole

(Encyclopedia)black hole, in astronomy, celestial object of such extremely intense gravity that it attracts everything near it and in some instances prevents everything, including light, from escaping. The term was...

Brockhouse, Bertram

(Encyclopedia)Brockhouse, Bertram, 1918–2003, Canadian physicist, b. Lethbridge, Alta. Educated at the Univ. of British Columbia and Univ. of Toronto (Ph.D., 1950), he was a research officer (1950–59) and head ...

Chadwick, Sir James

(Encyclopedia)Chadwick, Sir James, 1891–1974, English physicist, grad. Manchester Univ., 1908. He worked at Manchester under Ernest Rutherford on radioactivity. He was assistant director of radioactive research i...

star-of-Bethlehem, in botany

(Encyclopedia)star-of-Bethlehem, in botany, low, spring-blooming bulbous plant (Ornithogalum umbellatum) of the family Liliaceae (lily family), native to the Mediterranean region but naturalized in North America an...

hyperon

(Encyclopedia)hyperon hīˈpərŏnˌ [key], class of elementary particles heavier than nucleons (proton and neutron). The nucleons and the hyperons together make up the baryon family of particles. ...

proton

(Encyclopedia)proton, elementary particle having a single positive electrical charge and constituting the nucleus of the ordinary hydrogen atom. The positive charge of the nucleus of any atom is due to its protons....

gamma-ray astronomy

(Encyclopedia)gamma-ray astronomy, study of astronomical objects by analysis of the most energetic electromagnetic radiation they emit. Gamma rays are shorter in wavelength and hence more energetic than X rays (see...