Line Profiles ============== | HELIOS-K supports four different line profiles which can be set by the ``profile`` parameter. | The supported profiles are: - 1: Voigt - 2: Lorentz .. math:: :label: eq_fL f_L(\nu) = \frac{1}{\pi} \frac{\gamma_L}{(\nu - \nu_0)^2 + \gamma_L^2} - 3: Doppler .. math:: :label: eq_fG f_G(\nu) = \sqrt{\frac{ln(2)}{\pi}} \frac{1}{\alpha_D} \exp\left(-\frac{ (\nu - \nu_0)^2 ln(2)}{\alpha_D^2} \right) - 4: Binned Gaussian integrated cross section .. math:: :label: eq_sigma f_{BG} = \frac{1}{\Delta \nu} \int_{\nu - \nu/2}^{\nu + \nu/2} f_G(\nu) d \nu = \frac{1}{2 \Delta \nu} \left[ erf(\chi^+) - erf(\chi^-) \right] [Yurchenko et al. 2018: (ExoCross : a general program for generating spectra from molecular line lists)] with the Doppler half-width: .. math:: :label: eq_GD \alpha_D = \frac{\nu}{c} \sqrt{\frac{2 ln(2) k_B T}{m}} and the Lorentz half-width for Hitran like data: .. math:: :label: eqGL1 \gamma_L = \frac{A}{4\pi c} + \left( \frac{T}{T_{ref}}\right)^{-n} \left[ \frac{\alpha_{air} (P-P_{self})}{P_{ref}} + \frac{\alpha_{self} P_{self}}{P_{ref}}\right] or the Lorentz half-width for ExoMol like data: .. math:: :label: eqGL2 \gamma_L = \frac{A}{4\pi c} + \left( \frac{T_{ref}}{T} \right)^n \cdot \left( \frac{P}{P_{ref}}\right) or the Lorentz half-width for Atomic data: .. math:: :label: eqGL3 \gamma_L = \frac{\Gamma_{nat}}{4\pi c} + \left( \frac{T_{ref}}{T} \right)^n \cdot \left( \frac{P}{P_{ref}}\right) In :numref:`figprofile` is shown an example with four different line profiles. | Relevant parameters for this example: - doStoreFullK = 1 - profile = 1 or 2 or 3 or 4 .. figure:: ../../plots/p009/plot001.png :name: figprofile Example with four different line profiles