CODATA fundamental physical constants

CODATA 2022 recommended values of the fundamental physical constants, published by NIST (a US government work). One document per constant citing the NIST complete listing; refreshed on each CODATA release, roughly every four years.

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Documents

Showing 289–312 of 355 documents

Document	Version
quantum of circulation times 2 quantum of circulation times 2 = 7.273 895 0934 × 10⁻⁴ m² s⁻¹ (CODATA 2022 recommended value, NIST)	v1
reduced Compton wavelength reduced Compton wavelength = 3.861 592 6744 × 10⁻¹³ m (CODATA 2022 recommended value, NIST)	v2
reduced muon Compton wavelength reduced muon Compton wavelength = 1.867 594 306 × 10⁻¹⁵ m (CODATA 2022 recommended value, NIST)	v1
reduced neutron Compton wavelength reduced neutron Compton wavelength = 2.100 194 1520 × 10⁻¹⁶ m (CODATA 2022 recommended value, NIST)	v1
reduced Planck constant reduced Planck constant = 1.054 571 817… × 10⁻³⁴ J s (CODATA 2022 recommended value, NIST)	v2
reduced Planck constant in eV s reduced Planck constant in eV s = 6.582 119 569… × 10⁻¹⁶ eV s (CODATA 2022 recommended value, NIST)	v1
reduced Planck constant times c in MeV fm reduced Planck constant times c in MeV fm = 197.326 980 4… MeV fm (CODATA 2022 recommended value, NIST)	v1
reduced proton Compton wavelength reduced proton Compton wavelength = 2.103 089 100 51 × 10⁻¹⁶ m (CODATA 2022 recommended value, NIST)	v1
reduced tau Compton wavelength reduced tau Compton wavelength = 1.110 538 × 10⁻¹⁶ m (CODATA 2022 recommended value, NIST)	v1
Rydberg constant Rydberg constant = 10 973 731.568 157 m⁻¹ (CODATA 2022 recommended value, NIST)	v2
Rydberg constant times c in Hz Rydberg constant times c in Hz = 3.289 841 960 2500 × 10¹⁵ Hz (CODATA 2022 recommended value, NIST)	v1
Rydberg constant times hc in eV Rydberg constant times hc in eV = 13.605 693 122 990 eV (CODATA 2022 recommended value, NIST)	v1
Rydberg constant times hc in J Rydberg constant times hc in J = 2.179 872 361 1030 × 10⁻¹⁸ J (CODATA 2022 recommended value, NIST)	v1
Sackur-Tetrode constant (1 K, 100 kPa) Sackur-Tetrode constant (1 K, 100 kPa) = -1.151 707 534 96 (CODATA 2022 recommended value, NIST)	v1
Sackur-Tetrode constant (1 K, 101.325 kPa) Sackur-Tetrode constant (1 K, 101.325 kPa) = -1.164 870 521 49 (CODATA 2022 recommended value, NIST)	v1
second radiation constant second radiation constant = 1.438 776 877… × 10⁻² m K (CODATA 2022 recommended value, NIST)	v2
shielded helion gyromag. ratio shielded helion gyromag. ratio = 2.037 894 6078 × 10⁸ s⁻¹ T⁻¹ (CODATA 2022 recommended value, NIST)	v2
shielded helion gyromag. ratio in MHz/T shielded helion gyromag. ratio in MHz/T = 32.434 100 033 MHz T⁻¹ (CODATA 2022 recommended value, NIST)	v2
shielded helion mag. mom. shielded helion mag. mom. = -1.074 553 110 35 × 10⁻²⁶ J T⁻¹ (CODATA 2022 recommended value, NIST)	v2
shielded helion mag. mom. to Bohr magneton ratio shielded helion mag. mom. to Bohr magneton ratio = -1.158 671 494 57 × 10⁻³ (CODATA 2022 recommended value, NIST)	v2
shielded helion mag. mom. to nuclear magneton ratio shielded helion mag. mom. to nuclear magneton ratio = -2.127 497 7624 (CODATA 2022 recommended value, NIST)	v2
shielded helion to proton mag. mom. ratio shielded helion to proton mag. mom. ratio = -0.761 766 577 21 (CODATA 2022 recommended value, NIST)	v2
shielded helion to shielded proton mag. mom. ratio shielded helion to shielded proton mag. mom. ratio = -0.761 786 1334 (CODATA 2022 recommended value, NIST)	v2
shielded proton gyromag. ratio shielded proton gyromag. ratio = 2.675 153 194 × 10⁸ s⁻¹ T⁻¹ (CODATA 2022 recommended value, NIST)	v3

Source, review, and usage

Published on Koskamo by: Koskamo
Version: 468
Documents: 355 documents
Reviewed: 2026-10-03
Last approved change: 2026-10-04
Agent lookups: 71 in the last 90 days
Reuse: CODATA 2022 recommended values from NIST, a work of the US government (public domain in the United States)
Review status: Published by Koskamo; proposed revisions require Koskamo approval

Original sources are linked on each document. Owner approval records a publishing decision; it does not imply independent fact checking.

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Change history

Every change that reached this dataset. Proposals from contributors land only after Koskamo approves them.

Approved revision2026-10-04
Wien wavelength displacement law constant · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
weak mixing angle · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
von Klitzing constant · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
vacuum mag. permeability · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
vacuum electric permittivity · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
unified atomic mass unit · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
triton to proton mag. mom. ratio · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
triton mag. mom. to nuclear magneton ratio · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
triton mag. mom. to Bohr magneton ratio · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
triton mag. mom. · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.