Astrophysical computer programs

As part of my research work I have developed a number of Fortran and IDL astrophysical software packages. Contact me if you are interested in using these codes for educational or research purposes. Some of the programs are already available for download from dedicated webpages (see links in red below).

Doppler and Zeeman Doppler Imaging codes

Invers10 Magnetic (Zeeman) Doppler Imaging computer program for simultaneous and self-consistent reconstruction of the magnetic and chemical maps of the stellar surface using spectra in several Stokes parameters. This 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 designed to run on parallel computers using MPI libraries.

References: Piskunov & Kochukhov (2002, A&A, 381, 736), Kochukhov & Piskunov (2002, A&A, 388, 868), Kochukhov et al. (2002, A&A, 389, 420; 2004, A&A, 414, 613), Kochukhov & Wade (2010, A&A, 513, A13)

Invers12 Multi-element abundance Doppler Imaging code. It is able to reconstruct multiple chemical surface maps using high-resolution intensity observations of stellar spectra. The code is written in Fortran and is designed to run on parallel computers using MPI libraries.

References: Kochukhov et al. (2004, A&A, 424, 935), Nesvacil et al. (2012, A&A, 537, A151)

Invers13 Doppler imaging computer program for simultaneous reconstruction of vector magnetic field maps and distribution of temperature inhomogeneities in the late-type active stars. It can also be used to perform chemical mapping of early-type stars self-consistently with atmospheric structure. The code can use both atomic and molecular lines and to work in either circular polarization or full four Stokes parameter mode.

References: Kochukhov et al. (2012, MNRAS, 421, 3004; 2013, A&A, 550, A84), Rosén & Kochukhov (2012, A&A, 548, A8)

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/or stellar rotation.

References: Kochukhov (2004, A&A, 423, 613; 2004, ApJ, 615, L149)

InversLSD Code for performing regularized Magnetic Doppler Imaging inversions using least-squares deconvolved (LSD) profiles. The inversion procedure uses a library of precomputed synthetic LSD profiles obtained from full polarized spectrum synthesis calculations or using simplified analytical formulas. Magnetic field topology reconstruction is performed in terms of 2-D surface maps or poloidal and toroidal spherical harmonic components.

References: Kochukhov et al. (2014, A&A, 565, A83)

Least-squares deconvolution code

iLSD        Fortran code to perform least-squares addition of intensity and polarization spectra producing a very high signal-to-noise ratio mean line profile(s). Compared to standard LSD codes, iLSD includes a possibility to use multiple mean profiles (e.g. corresponding to spectral lines of different elements), iteratively adjust line weights, and smooth LSD profiles using regularization.

References: Kochukhov et al. (2010, A&A, 524, A5)

Spectrum synthesis codes

Synth3 This Fortran code calculates intensity stellar spectra for a given model atmosphere under the assumption of Local Thermodynamical Equilibrium (LTE). Synth3 is optimized for fast spectrum synthesis of large spectral intervals and includes molecular equilibrium solver. The latter enables a self-consistent computation of molecular absorption features as well as atomic spectral lines. A possibility to calculate spectra emergent from stellar atmospheres with a depth-dependent chemical composition and microturbulent velocity is included.

References: Kochukhov (2007, in Physics of Magnetic Stars, eds. I.I. Romanyuk and D. O. Kudryavtsev, 109)

Synth3 binaries for Mac and Linux OS and auxiliary programs are available for download

Synmast Further development of the SynthMag code by N. Piskunov. This code has the same capabilities as Synth3 but, in addition, allows to calculate four Stokes parameter stellar spectra for arbitrary magnetic field strength and orientation. Four Stokes parameter calculations are carried out by solving numerically polarized radiative transfer equation in a given stellar atmosphere.

References: Kochukhov (2007, in Physics of Magnetic Stars, eds. I.I. Romanyuk and D. O. Kudryavtsev, 109), Kochukhov et al. (2010, A&A, 524, A5)

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 Synmast or Synth3.

References: Ryabchikova et al. (2005, A&A, 438, 973), Kochukhov et al. (2009, A&A, 499, 851)

VIP A non-magnetic LTE spectrum inversion code capable of reconstructing an arbitrary smooth vertical distribution of chemical abundance from the simultaneous fit to many spectral line profiles.

References: Kochukhov et al. (2006, A&A, 460, 831)

IDL visualization programs

BinMag IDL widget program to examine theoretical stellar spectra computed with Synth/SynthMag/Synmast/Synth3 and compare them to observations. BinMag applies radial velocity shift and broadening to the theoretical spectra to account for the effects of stellar rotation, radial-tangential macroturbulence, instrumental smearing. The code can also simulate spectra of spectroscopic binary stars by appropriate coaddition of two synthetic spectra. Additionally, BinMag can be used to measure equivalent width, fit line profile shapes with analytical functions, and to automatically determine radial velocity and broadening parameters. BinMag interfaces with the Synth3 code and SME, allowing user to determine chemical abundances and stellar atmospheric parameters from the observed spectra.

BinMag distribution is available for download

FieldPlot IDL program to calculate and visualise surface distribution of magnetic field for several commonly used global magnetic field models.

IDL source file of FieldPlot is available for download

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).

GStokes distribution is available for download

DI_demo IDL widget program to illustrate Doppler Imaging inversion from time series of line profile observations. A user can construct surface distribution consisting of circular spots, generate simulated observations of line profile variability, and invert these observations testing different values of key parameters.

DI_demo distribution is available for download