ConstantID

Triton relative atomic mass

Atomic & nuclearMeasured

Ar(t) = 3.015 500 715 97(10)

Value
3.015 500 715 97
Standard uncertainty
1 × 10−10
Relative uncertainty
3.3 × 10−11 (33 parts per trillion)
Status
Measured
Symbol
Ar(t)
Source
CODATA 2022 via NIST · NIST entry

Use in a calculation

# triton relative atomic mass, CODATA 2022 (NIST)
triton_relative_atomic_mass = 3.01550071597  # standard uncertainty 1e-10

# SciPy: scipy.constants.physical_constants['triton relative atomic mass']

What it is

The mass of the triton, the nucleus of tritium (one proton and two neutrons), divided by the atomic mass constant (one twelfth of the mass of a carbon-12 atom). It has no 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).

triton relative atomic mass: CODATA values 1998–2022 relative to the 2022 value, in parts per trillion, with one-standard-uncertainty bars−150−100−500+50+100+150parts per trillion1998200220062010201420182022

Relative uncertainty

triton relative atomic mass: relative standard uncertainty in each CODATA adjustment, logarithmic scale10⁻¹²10⁻¹¹10⁻¹⁰1998200220062010201420182022
CODATAValue (uncertainty)Relative uncertaintyChange from previous
20223.015 500 715 97(10)3.3 × 10−11 −2.0 σ of 2018
20183.015 500 716 21(12)4.0 × 10−11

“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 mt/me Triton-electron mass ratio 5496.921 535 51(21) Atomic & nuclear gt Triton g factor 5.957 924 930(12) Atomic & nuclear μt Triton magnetic moment 1.504 609 5178(30) × 10−26 J T−1 Atomic & nuclear μt/μB Triton magnetic moment to Bohr magneton ratio 1.622 393 6648(32) × 10−3 Atomic & nuclear μt/μN Triton magnetic moment to nuclear magneton ratio 2.978 962 4650(59) Atomic & nuclear mt Triton mass 5.007 356 7512(16) × 10−27 kg Atomic & nuclear mtc2 Triton mass energy equivalent 4.500 387 8119(14) × 10−10 J Atomic & nuclear mtc2 Triton mass energy equivalent in MeV 2808.921 136 68(88) MeV