ConstantID

Electron gyromagnetic ratio

Atomic & nuclearMeasured

γe = 1.760 859 627 84(55) × 1011 s−1 T−1

Value
1.760 859 627 84 × 1011 s−1 T−1
Standard uncertainty
55 s−1 T−1
Relative uncertainty
3.1 × 10−10 (312 parts per trillion)
Status
Measured
Symbol
γe
Source
CODATA 2022 via NIST · NIST entry

Use in a calculation

# electron gyromagnetic ratio, CODATA 2022 (NIST)
electron_gyromagnetic_ratio = 1.76085962784e11  # s^-1 T^-1, standard uncertainty 55

# SciPy: scipy.constants.physical_constants['electron gyromag. ratio']

What it is

The ratio of magnetic moment to angular momentum for the electron, the lightest charged particle and the carrier of electric current in metals. In a magnetic field B the spin precesses at angular frequency γB; this is the basis of magnetic resonance.

How the value changed, 1998–2022

Each point is one CODATA adjustment, plotted as its difference from the 2022 value; the bars show one standard uncertainty (an arrowhead means the bar runs off the chart).

electron gyromagnetic ratio: CODATA values 1998–2022 relative to the 2022 value, in parts per billion, with one-standard-uncertainty bars−150−100−500+50+100+150parts per billion1998200220062010201420182022

Relative uncertainty

electron gyromagnetic ratio: relative standard uncertainty in each CODATA adjustment, logarithmic scale10⁻¹⁰10⁻⁹10⁻⁸10⁻⁷1998200220062010201420182022
CODATAValue (uncertainty)Relative uncertaintyChange from previous
20221.760 859 627 84(55) × 10113.1 × 10−10 −4.5 σ of 2018
20181.760 859 630 23(53) × 10113.0 × 10−10 −1.3 σ of 2014
20141.760 859 644(11) × 10116.2 × 10−9 −1.6 σ of 2010
20101.760 859 708(39) × 10112.2 × 10−8 −1.4 σ of 2006
20061.760 859 770(44) × 10112.5 × 10−8 +0.2 σ of 2002
20021.760 859 74(15) × 10118.5 × 10−8 −0.8 σ of 1998
19981.760 859 794(71) × 10114.0 × 10−8

“Change from previous” is the shift in the value divided by the standard uncertainty of the previous adjustment. Earlier values are converted into the current unit where NIST changed it (for example J s to J Hz⁻¹).

Related constants

Atomic & nuclear −e/me Electron charge to mass quotient −1.758 820 008 38(55) × 1011 C kg−1 Atomic & nuclear μe/μd Electron-deuteron magnetic moment ratio −2143.923 4921(56) Atomic & nuclear me/md Electron-deuteron mass ratio 2.724 437 107 629(47) × 10−4 Atomic & nuclear ge Electron g-factor −2.002 319 304 360 92(36) Atomic & nuclear γe/2π Electron gyromagnetic ratio in MHz/T 28 024.951 3861(87) MHz T−1 Atomic & nuclear me/mh Electron-helion mass ratio 1.819 543 074 649(53) × 10−4 Atomic & nuclear μe Electron magnetic moment −9.284 764 6917(29) × 10−24 J T−1 Atomic & nuclear ae Electron anomaly 1.159 652 180 46(18) × 10−3