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: 2 Search : red giant branch
red giant branch (RGB)
  شاخه‌ی ِ غولان ِ سرخ   
šâxe-ye qulân-e sorx

Fr.: branche des géantes rouges   

The evolutionary path of a star that has exhausted its available hydrogen content in the core, between the → main-sequence turnoff and the → helium flash.

red giant; → branch.

tip of the red giant branch method
  روش ِ نوک ِ شاخه‌ی غول‌های ِ سرخ   
raveš-e nok-e šâxe-ye qulhâ-ye sorx

Fr.: méthode du haut de la branche des géantes   

A technique for deriving extragalactic distances which uses the → luminosity of the brightest → red giant branch stars in old → stellar populations as a "standard candle." For old (> 2-3 Gyr), metal-poor ([Fe/H] < -0.7) stellar populations, this luminosity is relatively well determined, and the → absolute magnitude of these stars in the I band is roughly constant (MI = -4.1 ± 0.1).

M.E. tip; from M.L.G. or M.Du. tip "utmost point, extremity" (cf. Ger. zipfel, a diminutive formation); → red giant; → branch; → method.

Raveš, → method; nok "tip;" šâxé, → branch; qulhâ-ye sorx plural of qul-e sorx, → red giant.