Bibcode
Navarro, S. G.; Corradi, R. L. M.; Mampaso, A.
Referencia bibliográfica
Astronomy and Astrophysics, Volume 538, id.A76
Fecha de publicación:
2
2012
Revista
Número de citas
29
Número de citas referidas
23
Descripción
Context. As part of a project aimed at deriving extinction-distances for
thirty-five planetary nebulae, spectra of a few thousand stars were
analyzed to determine their spectral type and luminosity class.
Aims: We present here the automatic spectral classification process used
to classify stellar spectra. This system can be used to classify any
other stellar spectra with similar or higher signal-to-noise ratios. Methods: Spectral classification was performed using a system of
artificial neural networks that were trained with a set of line-strength
indices selected among the spectral lines most sensitive to temperature
and the best luminosity tracers. The training and validation processes
of the neural networks are discussed and the results of additional
validation probes, designed to ensure the accuracy of the spectral
classification, are presented. Results: Our system permits the
classification of stellar spectra of signal-to-noise ratio (S/N)
significantly lower than it is generally considered to be needed. For
S/N ≥ 20, a precision generally better than two spectral subtypes is
obtained. At S/N < 20, classification is still possible but has a
lower precision. Its potential to identify peculiar sources, such as
emission-line stars, is also recognized.
Based on observations obtained at the 4.2 m WHT telescope of the Isaac
Newton Group of Telescopes in the Spanish Observatorio del Roque de Los
Muchachos of the Instituto de Astrofísica de Canarias.
Proyectos relacionados
Nebulosas Bipolares
Nuestro proyecto persigue tres objetivos principales: 1) Determinar las condiciones físico-químicas de las nebulosas planetarias con geometría bipolar y de las nebulosas alrededor de estrellas simbióticas. El fin es entender el origen de la bipolaridad y poner a prueba los modelos teóricos que intentan explicar la morfología y la cinemática nebular
Antonio
Mampaso Recio