Computer programs for modelling stellar spectra

Here is a brief description of several Fortran and IDL astrophysical software packages which I am developing and maintaining. Contact me if you are interested in using these codes for your projects. Some of the programs are available for download here.

Doppler Imaging codes

Invers10 Computer program for simultaneous and self-consistent reconstruction of the magnetic and chemical maps of the stellar surface using spectra in all four Stokes parameters. Inversion procedure employs synthetic spectra calculated treating in detail polarized radiative transfer in the atmospheres of magnetic spotted stars. The code is written in Fortran and is optimized for running on massively parallel computers using MPI libraries.
Invers12 Improved version of the multi-element abundance Doppler Imaging procedure. The code is able to reconstructs multiple chemical surface maps using high-resolution intensity observations of stellar spectra. The code is written in Fortran and is optimized for running on massively parallel computers using MPI libraries.
Invers13 Doppler imaging computer program for simultaneous reconstruction of vector magnetic field maps and distribution of temperature inhomogeneities in the late-type active stars. The code is designed to use both atomic and molecular lines and to work in either circular polarization or full four Stokes parameter mode.
InversV Computer program for mapping distribution of pulsation velocity field over the surfaces of non-radially pulsating stars. The geometry of pulsations is recovered without parameterizing velocity field with the spherical harmonic functions. This allows to obtain two-dimensional image of non-radial pulsation modes distorted by magnetic field and stellar rotation.

Spectrum synthesis codes

Synmast Further development of the SynthMag code by N. Piskunov. This code calculates four Stokes parameter spectra of magnetic stars under the assumption of Local Thermodynamical Equilibrium (LTE). The code includes molecular equilibrium solver which enables a self-consistent computation of molecular absorption features as well as atomic spectral lines. A possibility to calculate spectra emergent from the stellar atmospheres with a depth-dependent chemical composition, microturbulent velocity and magnetic field is included.
Synth3 A non-magnetic analog of the SynthMag/Synmast code. Synth3 is optimized for fast LTE spectrum synthesis of large spectral intervals.

Vertical inversion codes

DDAFit A graphical interface and optimization tool for adjusting parameters of a simple step-function chemical stratification profile by fitting multiple spectral lines. Can be used in combination with either SynthMag/Synmast or Synth3.
VIP A non-magnetic LTE spectrum inversion code capable of reconstructing arbitrary vertical distribution of chemical abundance from the simultaneous fit to many spectral line profiles. Developed in collaboration with V. Tsymbal.

Visualization programs

BinMag IDL widget program to examine and compare with observations theoretical stellar spectra computed with Synth, SynthMag/Synmast and Synth3. BinMag provides a possibility to apply broadening of the theoretical spectra by stellar rotation, radial-tangential macroturbulence, instrumental smearing, and to simulate spectra of spectroscopic binary stars by appropriate coaddition of the two synthetic spectra. BinMag interfaces with the Synth3 code, allowing user to determine abundances from observations.
SPW IDL widget program to plot and perform simple operations on one-dimensional stellar spectra.
FieldPlot IDL program to calculate and visualise magnetic field geometry for different common global field models.
GStokes IDL widget program to calculate Stokes I and V line profile shapes and disk-integrated magnetic observables (mean longitudinal field, field modulus, etc.) using simple line formation models (weak-field approximation, Milne-Eddington atmosphere).

Visualization of calculated and observed stellar spectra with the BinMag program

Magnetic field structure and line profiles calculated with GStokes program

Quadrupolar magnetic field displayed with FieldPlot program