RaveSpan (Radial Velocity and Spectrum Analyzer) is an easy to use graphical application that brings together three major velocity
extraction methods: CCF, TODCOR, and Broadening Function (BF). All extracted
velocities are instantly plotted in the RV curve window. Selected orbital parameters may
be fitted afterwards.
RaveSpan is composed of several components. There is a spectrum viewer, where you
can inspect the collected spectra, compare them with templates, and choose a wavelength
range for your analysis. In the orbit viewer, one can see extracted velocities and a model
orbit. There is also an orbit fitting tool, with which one can fit selected orbital parameters.
The radial velocity analysis tool allows users to see the output of CCF, TODCOR or
BF and interactively fit several profiles of different types.
- Spectrum analysis. Currently three methods for velocity determination from spectra
are implemented. The simple cross-correlation method (CCF; Simkin 1974, Tonry &
Davis 1979 ), two dimensional cross-correlation (TODCOR; see Zucker & Mazeh 1994) and
the broadening function technique (BF; Rucinski 2002).
- Profile fitting. Once one of these functions is calculated, the maxima (or maximum)
are automatically detected and velocities evaluated. To improve accuracy, one of a few
types of profiles may be fitted. For CCF and BF response functions, we can fit up to 4 (it
is just set to 4 now, but may be increased easily) profiles, either Gaussian, rotational or
a simple polynomial one. With TODCOR, there is only one two-dimensional polynomial
- Radial velocity curve. All extracted velocities instantly appear in the radial velocity
curve window, where we can directly see the orbit shape and quality.
- Orbital parameters. Once we are ready with velocities, we can fit selected orbital parameters.
Third body influence and pulsational velocities of one or both components can
be included in the analysis and separated from the basic orbital motion.
Other features. This software allows for selection of different (preset by the user) wave-
length ranges for analysis. To allow for radial velocity determination, a normalization is
applied to the spectrum, unless a user disables the feature. For convenience, a Calculate
All function was implemented to explore different templates and spectrum ranges. This
function attempts to extract velocities from all the collected spectra in an automated
- Spectral disentangling. RaveSpan is also equiped with a simple Spectral disentangling mode with a spectral tomography method based on González & Levato (2006).
- Technical details. RaveSpan is written in pure Python using the PyQt4 graphical
library with Matplotlib as a plotting tool.
If you use RaveSpan for your publication, please cite one or more of these papers.
You may download the RaveSpan code from here .