Institute for Astronomy and Astrophysics

GAVO - German Astrophysical Virtual Observatory

The German Astrophysical Virtual Observatory (GAVO) is the German contribution to the IVOA (International Virtual Observatory Association), the international effort to create and expand the Virtual Observatory (VO).

The goals of the Virtual Observatory are

  • to allow or improve access to astronomical data of all kinds (astrometry, photometry, spectroscopy, time series,...), from everywhere, in well-defined protocols,
  • to let astronomers easily discover, access and use data relevant to them,
  • to ensure that data does not simply disappear, that it is properly described and can be accessed and understood in the future,
  • to provide software to help astronomers to use all this.

This huge programme is tackled under the auspices of the IVOA, which is formed by the various national VO organizations. These organizations run services and cooperate in IVOA to develop standards that let services in the VO talk to each other and to programs and libraries used by both astronomers and the general public. For Germany, these efforts are organized within GAVO.

Although certainly still in the process of being built, the VO is very much a reality. Thousands of "resources" (in VO speak this word means "something useful"), from the smallest catalog on VizieR to the large archive of SDSS, are waiting to be discovered and used - by you!

For more information, please have a look at GAVO.

Projects at Tübingen

In the framework of the GAVO project, we have developed the following services and tools:

  • TEUV: The Tübingen EUV absorption tool. It corrects synthetic stellar fluxes for interstellar absorption for λ < 911 Å. It simulates radiative bound-free absorption of the ground states of H I, He I - II, C I - III, N I - III, and O I - III using Opacity Project data.
  • TGRED: The Tübingen Gravitational REDshift calculator. It calculates the gravitational redshift and the radial velocity of a star.
  • TheoSSA: The Theoretical Stellar Spectra Access service provides easy access to pre-calculated spectral energy distributions (SEDs) of stellar model atmospheres.
  • TIRO: The Tübingen Iron group Opacity tool calculates bound-bound and bound-free absorption cross-sections for iron-group elements (Ca - Ni) based on Kurucz's data
  • TLISA: The Tübingen Line Identification and Spectrum Analyzer evaluates spectra and visualizes them.
  • TMAD: The Tübingen Model Atom Database service provides ready-to-use model atoms that can be individually adjusted for any model-atmosphere calculation.
  • TMAW: The Tübingen Model Atmosphere Web interface is helpful to calculate SEDs using our TMAP model atmosphere package.
  • TOSS: The Tübingen Oscillator Strength Service provides oscillator strengths and transition probabilities. Based on experimental energy levels, these were calculated with the pseudo-relativistic Hartree-Fock method including core-polarization corrections.
  • TVIS: The Tübingen Visualization tool allows to visualize two-dimensional data.