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- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/01%3A_Definitions_of_and_Relations_between_Quantities_used_in_Radiation_Theory/1.12%3A_Radiance_LSince 1979 we have gone one step further, recognizing that obtaining and measuring the radiation from a black body at the temperature of melting platinum is a matter of some practical difficulty, and ...Since 1979 we have gone one step further, recognizing that obtaining and measuring the radiation from a black body at the temperature of melting platinum is a matter of some practical difficulty, and the current definition of the candela makes no mention of platinum or of a black body, and the candela is defined in such a manner that if a source of monochromatic radiation of frequency \(5.4 \times 10^{14} \text{Hz}\) has a radiant intensity of \(1/683 \ \text{W sr}^{-1}\) in that direction, the…
- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/07%3A_Atomic_Spectroscopy/7.26%3A_Stark_EffectThe Stark effect concerns the separation of the states within a level as the result of the application of an external electric field, and the consequent splitting of lines into Stark components.
- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/04%3A_Flux_Specific_Intensity_and_other_Astrophysical_Terms/4.04%3A_FluxNow, using the nomenclature of stellar atmosphere theory, we call the rate of upward passage of radiant energy per unit area through a horizontal surface within the atmosphere the upward or the outwar...Now, using the nomenclature of stellar atmosphere theory, we call the rate of upward passage of radiant energy per unit area through a horizontal surface within the atmosphere the upward or the outward flux. Likewise, the rate of passage of radiant energy per unit area from above to below is the downward or inward flux, \(F_−\). If you are standing upright, \(F_+\) is the irradiance of the soles of your feet, while \(F_−\) is the irradiance of the top of your head.
- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/03%3A_The_Exponential_Integral_Function/3.01%3A_Section_1-
- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/03%3A_The_Exponential_Integral_Function/3.06%3A_Section_6-
- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/11%3A_Curve_of_GrowthIt will be part of the aim of this chapter to predict the curve of growth for gaussian and lorentzian profiles, and also for Voigt profile for different Gauss/Lorentz ratios. The curve of growth (die ...It will be part of the aim of this chapter to predict the curve of growth for gaussian and lorentzian profiles, and also for Voigt profile for different Gauss/Lorentz ratios. The curve of growth (die Wachstumskurve) is a graph showing how the equivalent width of an absorption line, or the radiance of an emission line, increases with the number of atoms producing the line.
- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/09%3A_Oscillator_Strengths_and_Related_Topics/9.09%3A_Summary_of_Relations_Between_f%2C_A_and_SIn this section I use \(ϖf\) to mean either \(ϖ_1 f_{12}\) or \(ϖ_2 f_{21}\), since these are equal; likewise I use \(ϖB\) to mean either \(ϖ_1 B_{12}\) or \(ϖ_2 B_{21}\). \[ϖ_2 A_{21} = \frac{8\pi hc...In this section I use \(ϖf\) to mean either \(ϖ_1 f_{12}\) or \(ϖ_2 f_{21}\), since these are equal; likewise I use \(ϖB\) to mean either \(ϖ_1 B_{12}\) or \(ϖ_2 B_{21}\). \[ϖ_2 A_{21} = \frac{8\pi hc}{\lambda^5} ϖB = \frac{2\pi e^2}{ε_0 mc \lambda^2} ϖf = \frac{16\pi^3}{3 h ε_0 \lambda^3} S ; \label{9.9.1}\] \[ϖB = \frac{e^2 \lambda^3}{4 h ε_0 mc^2}ϖf = \frac{2\pi^2 \lambda^2}{3 h^2 ε_0 c} S = \frac{\lambda^5}{8 \pi h c} ϖ_2 A_{21} ; \label{9.9.2}\]
- https://phys.libretexts.org/Bookshelves/Optics/Geometric_Optics_(Tatum)/02%3A_Lens_and_Mirror_Calculations/2.07%3A_ExamplesThe power of the first surface is \( \frac{1.5-1.0}{+20}\) cm −1 .The power of the second surface is \(\frac{1.0-1.5}{-30}\) cm −1 . Note that the radius of curvature of the second surface, when encou...The power of the first surface is \( \frac{1.5-1.0}{+20}\) cm −1 .The power of the second surface is \(\frac{1.0-1.5}{-30}\) cm −1 . Note that the radius of curvature of the second surface, when encountered by the light, is negative. The power, which is the reciprocal of the focal length, is the sum of the powers of the three interfaces:
- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/07%3A_Atomic_Spectroscopy/7.14%3A_States%2C_Levels%2C_Terms%2C_Polyads%2C_etc.In principle we could write out in full the complete wavefunction for each of these states, though it is simpler to write the wavefunction in the form of a \(ket |LSJM\rangle\), in which we merely lis...In principle we could write out in full the complete wavefunction for each of these states, though it is simpler to write the wavefunction in the form of a \(ket |LSJM\rangle\), in which we merely list the quantum numbers - because most of the operators encountered in quantum mechanics when acting upon the spherical harmonics result in similar functions with at most a change in the quantum numbers.
- https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Stellar_Atmospheres_(Tatum)/08%3A_Boltzmann's_and_Saha's_Equations/8.08%3A_Autoionization_and_Dielectronic_RecombinationOne of the electrons can easily slip away from the atom without the absorption of any additional energy, thereby leaving behind an ion in an excited state. Such a process is called autoionization, and...One of the electrons can easily slip away from the atom without the absorption of any additional energy, thereby leaving behind an ion in an excited state. Such a process is called autoionization, and the levels or states concerned are autoionization levels or states. The converse process is quite possible. An ion in an excited state can capture a hitherto free electron, thus forming the neutral atom with two excited electrons. The process is dielectronic recombination. Downward transitions fro
- https://phys.libretexts.org/Bookshelves/Classical_Mechanics/Classical_Mechanics_(Tatum)/11%3A_Simple_and_Damped_Oscillatory_Motion/11.05%3A_Damped_Oscillatory_Motion/11.5iii%3A_Critical__damping-_(_gamma_%3D_2omega_0)In order that the coil and the pointer should move to the equilibrium position in the fastest possible time without oscillating, the system should be critically damped - which means that the rotationa...In order that the coil and the pointer should move to the equilibrium position in the fastest possible time without oscillating, the system should be critically damped - which means that the rotational inertia and the electrical resistance of the little aluminium former has to be carefully designed to achieve this.
