Nuclear Physics

The nucleus
Applications
Particle accelerators

### Some Fundamental Physical Constants

Quantity Symbol, equation Value
standard gravitational accel. g9.806 65 m s-2
speed of light in vacuum c 299 792 458 m s-1
Planck constant h 6.626 068 96 x10-34 J s
Planck constant, reduced ℏ = h/2π 1.054 571 628 x10-34 J s = 6.582 118 99 x 10-22 MeV s
electron charge magnitude e 1.602 176 487 x10-19 C = 4.803 204 27 x 10--10 esu
conversion constant ℏc 197.326 9631 MeV fm
conversion constant 2 0.389 379 304 GeV2 mbarn
electron mass me 0.510 998 910 MeV/c2 = 9.109 382 15 x 10-31 kg
proton mass mp 938.272 013 MeV/c2 = 1.672 621 637 x 10-27 kg = 1.007 276 466 77 u = 1836.152 672 47me
unified atomic mass unit (u) (mass 12C atom)/12 = (1 g)/(NA mol) 931.494 028 MeV/c2 = 1.660 538 782 x 10-27 kg
permittivity of free space ε0 = 1/μ0c2 8.854 187 817 x 10-12 F m-
permeability of free space μ0 = 4π x 10-7 N A-2 12.566 370 614 x 10-7 N A-2
fine-structure constant α = e2/4πε0ℏc 7.297 352 5376 x 10-3 = 1/137.035 999
classical electron radius re = e2/4πε0 mec2 2.817 940 2894 x 10-15 m
(e- Compton wavelength)/2π λ = ℏ/mec = reα-1 3.861 592 6459 x 10-13 m
Bohr radius (mmnucleus = ∞) a = 4πε02/mee2 = reα-2 0.529 177 208 59 x 10 -10 m
Rydberg energy hcR = mee4/2(4πε0)22 = mec2α2/2 13.605 691 93 eV
Thomson cross section σT = 8πre2/3 0.665 245 8558 barn
Bohr magneton μB = eℏ/2me 5.788 381 7555 x 10-11 MeV T-1
nuclear magneton μN = eℏ/2mp 3.152 451 2326 x 10-14 MeV T-1
Avogadro constant NA 6.022 141 79 x 1023mol-1
Boltzmann constant k 1.380 6504 x10-23 J K-1 = 8.617 343x10-5 eV K-1
molar volume, ideal gas at STP NAk(273.15 K)/(101 325 Pa) 22.413 996 x 10-3 m3 mol-1
Wien displacement law constant b = λmaxT 2.897 7685x10-3 m K
Stefan-Boltzmann constant σ = π2k4/60ℏ3c2 5.670 400 x 10-8 W m-2 K-4

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1 Å = 0.1 nm 1 barn = 10-28 m2
1 erg = 10-7J  1 eV = 1.602 176 487 x 10-19 J
0 oC = 273.15 K kT at 300 K = [38.681 685]-1 eV
1 atmosphere = 760 Torr = 101 325 Pa   1 C = 2.997 924 58 x 109esu

1 dyne = 10-5 N  1 eV/c2 = 1.782 661 758 x 10--36 kg

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