# Default Pint constants definition file # Based on the International System of Units # Language: english # Source: https://physics.nist.gov/cuu/Constants/ # https://physics.nist.gov/PhysRefData/XrayTrans/Html/search.html # :copyright: 2013,2019 by Pint Authors, see AUTHORS for more details. #### MATHEMATICAL CONSTANTS #### # As computed by Maxima with fpprec:50 pi = 3.1415926535897932384626433832795028841971693993751 = π = 派 = 圆周率 # pi tansec = 4.8481368111333441675396429478852851658848753880815e-6 # tangent of 1 arc-second ~ arc_second/radian ln10 = 2.3025850929940456840179914546843642076011014886288 # natural logarithm of 10 wien_x = 4.9651142317442763036987591313228939440555849867973 # solution to (x-5)*exp(x)+5 = 0 => x = W(5/exp(5))+5 wien_u = 2.8214393721220788934031913302944851953458817440731 # solution to (u-3)*exp(u)+3 = 0 => u = W(3/exp(3))+3 eulers_number = 2.71828182845904523536028747135266249775724709369995 = 欧拉数 #### DEFINED EXACT CONSTANTS #### speed_of_light = 299792458 m/s = c = c_0 = 光速 # since 1983 planck_constant = 6.62607015e-34 J s = ℎ = 普朗克常数 = 普朗克常量 # since May 2019 elementary_charge = 1.602176634e-19 C = e = 基本电荷 = 基本电量 = 元电荷 # since May 2019 avogadro_number = 6.02214076e23 = 阿伏伽德罗数 # since May 2019 boltzmann_constant = 1.380649e-23 J K^-1 = k = k_B = 玻尔兹曼常数 = 玻尔兹曼常量 # since May 2019 standard_gravity = 9.80665 m/s^2 = g_0 = g0 = g_n = gravity = 标准重力 = 重力 = 重力加速度 # since 1901 standard_atmosphere = 1.01325e5 Pa = atm = atmosphere = 标准大气压 = 大气压 # since 1954 conventional_josephson_constant = 4.835979e14 Hz / V = K_J90 = 常规约瑟夫逊常数 = 常规约瑟夫逊常量 # since Jan 1990 conventional_von_klitzing_constant = 2.5812807e4 ohm = R_K90 = 常规冯克利青常数 = 常规冯克利青常量 # since Jan 1990 #### DERIVED EXACT CONSTANTS #### # Floating-point conversion may introduce inaccuracies zeta = c / (cm/s) = ζ dirac_constant = ℎ / (2 * π) = ħ = hbar = atomic_unit_of_action = a_u_action = 约化普朗克常数 = 约化普朗克常量 = 狄拉克常数 = 狄拉克常量 avogadro_constant = avogadro_number * mol^-1 = N_A = 阿伏伽德罗常数 = 阿伏伽德罗常量 molar_gas_constant = k * N_A = R = 摩尔气体常数 = 通用气体常数 = 理想气体常数 = 普适气体常数 = 摩尔气体常量 = 通用气体常量 = 理想气体常量 = 普适气体常量 faraday_constant = e * N_A = 法拉第常数 = 法拉第常量 conductance_quantum = 2 * e ** 2 / ℎ = G_0 = 电导量子 magnetic_flux_quantum = ℎ / (2 * e) = Φ_0 = Phi_0 = 磁通量量子 josephson_constant = 2 * e / ℎ = K_J= 约瑟夫逊常数 = 约瑟夫逊常量 von_klitzing_constant = ℎ / e ** 2 = R_K = 冯克利青常数 = 冯克利青常量 stefan_boltzmann_constant = 2 / 15 * π ** 5 * k ** 4 / (ℎ ** 3 * c ** 2) = σ = sigma = 斯特藩-玻尔兹曼常数 = 斯特藩常数 = 斯特藩常量 = 斯特藩-玻尔兹曼常量 first_radiation_constant = 2 * π * ℎ * c ** 2 = c_1 = 第一辐射常数 = 第一辐射常量 second_radiation_constant = ℎ * c / k = c_2 = 第二辐射常数 = 第二辐射常量 wien_wavelength_displacement_law_constant = ℎ * c / (k * wien_x) = 维恩波长位移常数 = 维恩波长位移常量 wien_frequency_displacement_law_constant = wien_u * k / ℎ = 维恩频率位移常数 = 维恩频率位移常量 #### MEASURED CONSTANTS #### # Recommended CODATA-2018 values # To some extent, what is measured and what is derived is a bit arbitrary. # The choice of measured constants is based on convenience and on available uncertainty. # The uncertainty in the last significant digits is given in parentheses as a comment. newtonian_constant_of_gravitation = 6.67430e-11 m^3/(kg s^2) = _ = gravitational_constant = 牛顿重力常数 = 万有引力常数 = 重力常数 = 牛顿常数 = 牛顿重力常量 = 万有引力常量 = 重力常量 = 牛顿常量 # (15) rydberg_constant = 1.0973731568160e7 * m^-1 = R_∞ = R_inf = 里德伯常量 = 里德伯常数 # (21) electron_g_factor = -2.00231930436256 = g_e = 电子g因子 # (35) atomic_mass_constant = 1.66053906660e-27 kg = m_u = 原子质量常数 = 原子质量常量 # (50) electron_mass = 9.1093837015e-31 kg = m_e = atomic_unit_of_mass = a_u_mass = 电子质量 # (28) proton_mass = 1.67262192369e-27 kg = m_p = 质子质量 # (51) neutron_mass = 1.67492749804e-27 kg = m_n = 中子质量 # (95) lattice_spacing_of_Si = 1.920155716e-10 m = d_220 = 硅的晶格常数 # (32) K_alpha_Cu_d_220 = 0.80232719 # (22) K_alpha_Mo_d_220 = 0.36940604 # (19) K_alpha_W_d_220 = 0.108852175 # (98) #### DERIVED CONSTANTS #### fine_structure_constant = (2 * ℎ * R_inf / (m_e * c)) ** 0.5 = α = alpha = 精细结构常数 = 精细结构常量 vacuum_permeability = 2 * α * ℎ / (e ** 2 * c) = µ_0 = mu_0 = mu0 = magnetic_constant = 真空磁导率 = 自由空间磁导率 = 磁常数 = 磁场常数 = 磁常量 = 磁场常量 vacuum_permittivity = e ** 2 / (2 * α * ℎ * c) = ε_0 = epsilon_0 = eps_0 = eps0 = electric_constant = 真空电容率 = 真空介电系数 = 电常数 = 电常量 impedance_of_free_space = 2 * α * ℎ / e ** 2 = Z_0 = characteristic_impedance_of_vacuum = 自由空间阻抗 coulomb_constant = α * hbar * c / e ** 2 = k_C = 库仑常数 = 库仑常量 classical_electron_radius = α * hbar / (m_e * c) = r_e = 经典电子半径 thomson_cross_section = 8 / 3 * π * r_e ** 2 = σ_e = sigma_e = 汤姆逊散射截面