Proton Compton wavelength
Atomic & nuclearMeasured
= 1.321 409 853 60(41) × 10−15 m
- Value
- 1.321 409 853 60 × 10−15 m
- Standard uncertainty
- 4.1 × 10−25 m
- Relative uncertainty
- 3.1 × 10−10 (310 parts per trillion)
- Status
- Measured
- Symbol
- Source
- CODATA 2022 via NIST · NIST entry
Use in a calculation
# proton Compton wavelength, CODATA 2022 (NIST)
proton_compton_wavelength = 1.3214098536e-15 # m, standard uncertainty 4.1e-25
# SciPy: scipy.constants.physical_constants['proton Compton wavelength']What it is
The wavelength of a photon whose energy equals the rest energy of the proton, the nucleus of the hydrogen atom: h/(mc).
In other units
| Unit | Value | |
|---|---|---|
| CGS (cm) | 1.321 409 8536 × 10−13 | |
| pm picometre | 0.001 321 409 8536 | |
| fm femtometre | 1.321 409 8536 |
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 | 1.321 409 853 60(41) × 10−15 | 3.1 × 10−10 | −4.5 σ of 2018 |
| 2018 | 1.321 409 855 39(40) × 10−15 | 3.0 × 10−10 | +2.3 σ of 2014 |
| 2014 | 1.321 409 853 96(61) × 10−15 | 4.6 × 10−10 | −2.4 σ of 2010 |
| 2010 | 1.321 409 856 23(94) × 10−15 | 7.1 × 10−10 | +6.1 σ of 2006 |
| 2006 | 1.321 409 8446(19) × 10−15 | 1.4 × 10−9 | −1.2 σ of 2002 |
| 2002 | 1.321 409 8555(88) × 10−15 | 6.7 × 10−9 | +0.8 σ of 1998 |
| 1998 | 1.321 409 847(10) × 10−15 | 7.6 × 10−9 |
“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).