|
In physics, the gyromagnetic ratio (also sometimes known as the magnetogyric ratio in other disciplines) of a particle or system is the ratio of its magnetic dipole moment to its angular momentum, and it is often denoted by the symbol γ, gamma. Its SI unit is the radian per second per tesla (rad⋅s−1⋅T−1) or, equivalently, the coulomb per kilogram (C⋅kg−1). The term "gyromagnetic ratio" is sometimes used〔For example, see: D.C. Giancoli, ''Physics for Scientists and Engineers'', 3rd ed., page 1017. Or see: P.A. Tipler and R.A. Llewellyn, ''Modern Physics'', 4th ed., page 309.〕 as a synonym for a ''different'' but closely related quantity, the g-factor. The g-factor, unlike the gyromagnetic ratio, is dimensionless. For more on the g-factor, see below, or see the article g-factor. ==Gyromagnetic ratio and Larmor precession== (詳細はnucleus, or an electron, when placed in an external magnetic field ''B'' (measured in teslas) that is not aligned with its magnetic moment, will precess at a frequency ''f'' (measured in hertz), that is proportional to the external field: : For this reason, values of ''γ''/(2''π''), in units of hertz per tesla (Hz/T), are often quoted instead of ''γ''. This relationship also explains an apparent contradiction between the two equivalent terms, gyromagnetic ratio versus magnetogyric ratio: whereas it is a ratio of a magnetic property (i.e. dipole moment) to a ''gyric'' (rotational, from (ギリシア語:γύρος), "turn") property (i.e. angular momentum), it is also, ''at the same time'', a ratio between the angular precession frequency (another ''gyric'' property) and the magnetic field. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Gyromagnetic ratio」の詳細全文を読む スポンサード リンク
|