Fast approximation of angle-dependent partial redistribution in moving atmospheres

Abstract

Radiative transfer modeling of spectral lines including partial redistribution (PRD) effects requires the evaluation of the ratio of the emission to the absorption profile. This quantity requires a large amount of computational work if one employs the angle-dependent redistribution function, which prohibits its use in 3D radiative transfer computations with model atmospheres containing velocity fields. We aim to provide a method to compute the emission to absorption profile ratio that requires less computational work but retains the effect of angle-dependent scattering in the resulting line profiles. We present a method to compute the profile ratio that employs the angle-averaged redistribution function and wavelength transforms to and from the rest frame of the scattering particles. We compare the emergent line profiles of the \MgII\,k and \Lyalpha\ lines computed with angle-dependent PRD, angle-averaged PRD and our new method in two representative test atmospheres. The new method yields a good approximation of true angle-dependent profile ratio and the resulting emergent line profiles while keeping the computational speed and simplicity of angle-averaged PRD theory.

Accepted for publication in A&A

References in corpus (1)

• The formation of the Halpha line in the solar chromosphere

Cited by in corpus (55)

• Evidence of Non-Thermal Particles in Coronal Loops Heated Impulsively by Nanoflares
• On the generation of solar spicules and Alfvénic waves
• The formation of IRIS diagnostics I. A quintessential model atom of Mg II and general formation properties of the Mg II h&k lines
• STiC -- A multi-atom non-LTE PRD inversion code for full-Stokes solar observations
• The formation of IRIS diagnostics. III. Near-ultraviolet Spectra and Images
• Bombs and flares at the surface and lower atmosphere of the Sun
• RH 1.5D: a massively parallel code for multi-level radiative transfer with partial frequency redistribution and Zeeman polarisation
• The Formation of IRIS diagnostics. IV. The Mg II triplet lines as a new diagnostic for lower chromospheric heating
• Non-LTE inversions of the Mg II h&k and UV triplet lines
• The Atmospheric Response to High Nonthermal Electron Beam Fluxes in Solar Flares I: Modeling the Brightest NUV Footpoints in the X1 Solar Flare of 2014 March 29
• Simulations of the Mg II k and Ca II 8542 lines from an Alfvén Wave-heated flare chromosphere
• Intermittent reconnection and plasmoids in UV bursts in the low solar atmosphere
• Radiative diagnostics in the solar photosphere and chromosphere
• Data-driven Radiative Hydrodynamic Modeling of the 2014 March 29 X1.0 Solar Flare
• Transverse Wave Induced Kelvin-Helmholtz Rolls in Spicules
• Partial redistribution in 3D non-LTE radiative transfer in solar atmosphere models
• A parameter study for modeling MgII h and k emission during solar flares
• Dissecting bombs and bursts: non-LTE inversions of low-atmosphere reconnection in SST and IRIS observations
• Modeling Mg II h, k and Triplet Lines at Solar Flare Ribbons
• On chromospheric heating during flux emergence in the solar atmosphere
• An observationally-constrained model of strong magnetic reconnection in the solar chromosphere. Atmospheric stratification and estimates of heating rates
• Stratification of physical parameters in a C-class solar flare using multi-line observations
• The Lightweaver Framework for NLTE Radiative Transfer in Python
• Modelling Mg II During Solar Flares. I. Partial Frequency Redistribution, Opacity, and Coronal Irradiation
• Spatio-temporal analysis of chromospheric heating in a plage region
• Solar Flare Ribbon Fronts I: Constraining flare energy deposition with IRIS spectroscopy
• Semi-empirical model atmospheres for the chromosphere of the sunspot penumbra and umbral flashes
• Efficient Calculation of Non-Local Thermodynamic Equilibrium Effects in Multithreaded Hydrodynamic Simulations of Solar Flares
• Discrete diffusion Lyman-alpha radiative transfer
• Modeling the scattering polarization of the solar Ca i 4227 Å line with angle-dependent partial frequency redistribution
• 1.5D NLTE spectral synthesis of a 3D filament/prominence simulation
• Prospects of Detecting Non-thermal Protons in Solar Flares via Lyman Line Spectroscopy: Revisiting the Orrall-Zirker Effect
• Solar surges related to UV bursts: Characterization through k-means, inversions and density diagnostics
• Evidence of multithermal nature of spicular downflows. Impact on solar atmospheric heating
• Mg ii h&k spectra of an enhanced network region simulated with the MURaM-ChE code. Results using 1.5D synthesis
• Properties of shock waves in the quiet Sun chromosphere
• Spatio-temporal evolution of Hanle and Zeeman synthetic polarization in a chromospheric spectral line
• Chromospheric Heating from Local Magnetic Growth and Ambipolar Diffusion Under Non-Equilibrium Conditions
• $IRI{S}^{2+}$: A comprehensive database of stratified thermodynamic models in the low solar atmosphere
• Constraining the systematics of (acoustic) wave heating estimates in the solar chromosphere
• Formation of H$\epsilon$ in the solar atmosphere
• The formation and heating of chromospheric fibrils in a radiation-MHD simulation
• Radiative losses in the chromosphere during a C-class flare
• Assessment of the CRD approximation for the observer's frame RIII redistribution matrix
• Temperature diagnostics of chromospheric fibrils
• Does H$\alpha$ Stokes~$V$ profiles probe the chromospheric magnetic field? An observational perspective
• Simultaneous spectropolarimetric observations in the H$\alpha$ and Ca II 8662 Å lines of an active region
• A numerical approach for modelling the polarisation signals of strong resonance lines with partial frequency redistribution. Numerical applications to two-term atoms and plane-parallel atmospheres
• Diagnostic potential of wavelength-integrated scattering polarisation signals of the solar He II Ly-alpha line
• Transverse oscillations in 3D along Ca II K bright fibrils in the solar chromosphere
• Spectral Characteristics of a Rotating Solar Prominence in Multiple Wavelengths
• Jacobian-Free Newton-Krylov method for multilevel NLTE radiative transfer problems
• The magnetic sensitivity of the Ca II H and K lines
• Decay of a photospheric transient filament at the boundary of a pore and the chromospheric response
• On the (mis)interpretation of the scattering polarization signatures in the Ca II 8542 A line through spectral line inversions