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Companions to PN central stars

Summary

This will is a test case for use of theoretical models in the VO context. The capabilities of this demo can easily be extended to make use of the full informational content of the high resolution spectral model, e.g. it could be applied to UVES data.

People

• F. Kerber (ST-ECF),
• T. Rauch (Univ. Bamberg),
• R. Mignani (ESO),
• A. Micol (AVO, ST-ECF),
• ESO's AVO Team < esodev@euro-vo.org >,
• GAVO Team < gavo@mpe.mpg.de >

Workflow

• The input catalogue of PN coordinates (Kerber et al. 2003) is cross-correlated with GSC-II, 2MASS and DENIS. The magnitudes (optical and near IR, with errors) are extracted and a SED is constructed.
• The model atmospheres (Rauch) are used to create model SEDs employing the filter curves of the comparison catalogues.
• The observed SED is then compared with a library of model SEDs and the best match(es) are found. This classification gives an estimate of the temperature of the CS.
• Objects with an IR excess are candidates for binarity and will be investigated further.

Data Requirements

• primary input: PN coordinates (Kerber et al. 2003), available from VizieR
• other input catalogues: GSC-II, 2MASS, DENIS, all available from VizieR
• model spectra
• formulae and zero points for magnitude to flux conversion
• 2MASS Photometric System

Key Algorithms

• automatic cross-matcher between the different catalogues using a VizieR query
• classifier for comparison of observed and model SEDs

Status

• Feasibility has been demonstrated, automation of the processes is in preparation.
• A collaboration with GAVO has been started, two requirements documents concerning the matcher and classifier have been issued (H.-M. Adorf):
  • Requirements for accesing and matching catalogs of PNes (.doc)
  • SED Classifier Requirements (.doc)
• Flux converted model spectra and reference SEDs were delivered to GAVO on July 29th, 04
• Implementation is planned for the near future.

-- FlorianKerber - 03 Jun 2004

Attachment Action Size Date Uploaded by Comment Datadownloadandmatchingrequirements.doc manage 70.5 K 03 Jun 2004 - 14:36 MarkusDolensky Reqs for accessing and matching PNes by Adorf SEDclassifierrequirements.doc manage 64.0 K 03 Jun 2004 - 14:37 MarkusDolensky Reqs for SED classifier by Adorf zeropoints.txt manage 0.5 K 29 Jul 2004 - 09:25 AlbertoMicol Zeropoints used to convert Johnson mag to Flambda SED_mag_to_flux.txt manage 1.2 K 29 Jul 2004 - 10:09 AlbertoMicol Formulae to transform SED mags into Fluxes(lambda)