Atomic mass constant energy equivalent in MeV
Physico-chemicalMeasured
= 931.494 103 72(29) MeV
- Value
- 931.494 103 72 MeV
- Standard uncertainty
- 2.9 × 10−7 MeV
- Relative uncertainty
- 3.1 × 10−10 (311 parts per trillion)
- Status
- Measured
- Symbol
- Source
- CODATA 2022 via NIST · NIST entry
Use in a calculation
Plain
LaTeX
Python
# atomic mass constant energy equivalent in MeV, CODATA 2022 (NIST)
atomic_mass_constant_energy_equivalent_i = 9.3149410372e2 # MeV, standard uncertainty 2.9e-7
# SciPy: scipy.constants.physical_constants['atomic mass constant energy equivalent in MeV']What it is
The atomic mass constant energy equivalent expressed in mega-electronvolts.
In other units
| Unit | Value | |
|---|---|---|
| CGS (cm2 g s−2) | 0.001 492 418 0877 | |
| keV kiloelectronvolt | 931 494.103 72 | |
| GeV gigaelectronvolt | 0.931 494 103 72 | |
| erg erg | 0.001 492 418 0877 |
Converted with ConstantID's unit table; digits are rounded to the precision of the value, and a long exact value is rounded only for display. The relative uncertainty is unchanged by conversion to an exactly defined unit.
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).
Relative uncertainty
| CODATA | Value (uncertainty) | Relative uncertainty | Change from previous |
|---|---|---|---|
| 2022 | 931.494 103 72(29) | 3.1 × 10−10 | +4.6 σ of 2018 |
| 2018 | 931.494 102 42(28) | 3.0 × 10−10 | +1.2 σ of 2014 |
| 2014 | 931.494 0954(57) | 6.1 × 10−9 | +1.6 σ of 2010 |
| 2010 | 931.494 061(21) | 2.3 × 10−8 | +1.4 σ of 2006 |
| 2006 | 931.494 028(23) | 2.5 × 10−8 | −0.2 σ of 2002 |
| 2002 | 931.494 043(80) | 8.6 × 10−8 | +0.8 σ of 1998 |
| 1998 | 931.494 013(37) | 4.0 × 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).