An Etymological Dictionary of Astronomy and Astrophysics
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Same as → weak interaction.

→ weak; → nuclear; → force.

A → semiempirical → equation which describes the → binding energy of the → atomic nucleus. It is essentially a nuclear mass formula that provides the total binding energy per → nucleon as the sum of five terms:
E_b = a_VA - a_SA^2/3 - a_CZ²/A^1/3 - a_A(N -Z)²/A + δ(A,Z),
where the terms in the right-hand side of this equation are called the volume term, surface term, Coulomb term, asymmetry term, and pairing term, respectively. A, Z, and N are the number of nucleons, → protons, and → neutrons, respectively (see, e.g., Alexi M. Frolov, 2013, arxiv.org/pdf/1212.6768). Also called Bethe-Weizacker formula and → semiempirical binding energy formula.

Named after Carl Friedrich von Weizäcker (1912-2007), German physicist, who derived the formula in 1935, Z. für Physik 96, 431; → formula.

A string of → symbols from the alphabet of the → formal language that conforms to the grammar of the formal language. → closed wff, → open wff.

Wff, pronounced whiff; → well; → form; → formula.

An international collaboration, more accurately named SuperWASP, led by the United Kingdom, that aims at detecting → extrasolar planets by means of the → transit method. SuperWASP consists of two robotic observatories that operate continuously all year around, providing coverage of the sky in both hemispheres. The first, SuperWASP-North, is located on the island of La Palma. The second, SuperWASP-South, is located at the site of the South African Astronomical Observatory (SAAO). The observatories each consist of eight wide-angle cameras that simultaneously monitor the sky for → planetary transit events. Using the array of cameras makes it possible to monitor millions of stars simultaneously at an → apparent visual magnitude from about 7 to 13.

→ wide; → angle; → search; → planet.

A spectral feature at 9850-10200 Å appearing in the spectrum of some late-type → M dwarfs. It is attributed to iron hybrid (FeH), a typical signature of the atmospheres of the coolest stars.

First detected by R. F. Wing and W. K. Ford (1969, PASP 81, 527); → band.