An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 26 Search : atomic
interatomic
  اندر-اتومی   
andaratomi

Fr.: interatomique   

Between atoms; relating to the interaction of different atoms.

inter-; → atomic.

International Atomic Time (TAI)
  زمان ِ اتمی ِ جهانی   
zamân-e atomi-ye jahâni (#)

Fr.: Temps Atomique International (TAI)   

A weighted average of the time kept by about 200 caesium atomic clocks in over 50 national laboratories worldwide. It has been available since 1955, and became the international standard on which UTC is based on January 1972.

international; → atomic; → time.

relative atomic mass
  جرم ِ اتمی ِ بازانی   
jerm-e atomi-ye bâzâni

Fr.: masse atomique relative   

The ratio of the mass of an atom of the → chemical element to one-twelfth the mass of an atom of carbon-12. Because an element in nature is usually a mixture of isotopes, the relative atomic mass is also the weighted mean of the atomic masses of all the atoms in a particular sample of the element, weighted by isotopic abundance. In this sense, relative atomic mass was once known as → atomic weight.

relative; → atomic; → mass.

subatomic
  زیر-اتمی   
zir-atomi (#)

Fr.: subatomique   

Of, relating to, or being smaller than the atom; of or relating to the inside of the atom.

sub-; → atomic.

subatomic particle
  ذره‌ی ِ زیر-اتمی   
zarre-ye zir-atomi (#)

Fr.: particule subatomique   

Any particle that is small compared to the size of the atom, e.g. an electron, proton, neutron, neutrino, quark, meson, all of which are either bosons or fermions.

subatomic; → particle.

triatomic hydrogen molecular ion
  یون ِ مولکولی ِ سه‌اتمی ِ هیدروژن   
yon-e molekuli-ye se-atomi-ye hidrožen

Fr.: ion moléculaire d'hydrogène triatomique, H3+   

The hydrogen molecule composed of three atoms in which one of the atoms is ionized. The molecular ion H3+ plays a key role in the chemistry of gaseous → interstellar medium. It reacts efficiently with almost any neutral atom or molecule to initiate a network of ion-neutral reactions. It is responsible for producing molecules such as OH, CO, and H2O. The first detection of H3+ in the interstellar medium, via two closely spaced absorption lines (doublet) near 3.668 μm, were reported in two dense → molecular cloud cores along the lines of sight to the embedded → young stellar objects W33A and GL2136 (Geballe & Oka 1996). Since then H3+ has been detected in several molecular clouds. It is believed that H3+ forms via → cosmic ray → ionization of H2 producing H2+, which quickly reacts to another H2 molecule to form H3+ ( H2 + CR → H2+ and H2+ + H2→ H3+ + H + 1.7 eV).

Tri-, → three; → atomic; → hydrogen; → molecular; → ion.

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