Automatic selection of new Hα emission-line galaxies using MAMA

A full set of algorithms for the automatic analysis of low-resolution objective-prism spectra has been developed with the aim of finding new emission-line galaxies (ELGs) candidates from the Universidad Complutense de Madrid (UCM) survey prism plates. An objective-prism plate and a direct plate, use...

ver descrição completa

Detalhes bibliográficos
Autores: Alonso, O., Zamorano Calvo, Jaime, Rego Fernández, Manuel, Gallego Maestro, Jesús
Formato: artículo
Fecha de publicación:1995
País:España
Recursos:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/57988
Acesso em linha:https://hdl.handle.net/20.500.14352/57988
Access Level:acceso abierto
Palavra-chave:52
Objective-prism survey
Quasars
Spectra
Plates
Astrofísica
Astronomía (Física)
Descrição
Resumo:A full set of algorithms for the automatic analysis of low-resolution objective-prism spectra has been developed with the aim of finding new emission-line galaxies (ELGs) candidates from the Universidad Complutense de Madrid (UCM) survey prism plates. An objective-prism plate and a direct plate, used for pairing objects and to perform star-galaxy separation, have been scanned with the MAMA machine. The plates were taken in the red region of the spectrum, using the Hα+[NII] blend in emission as selection criterion. The procedure, applied to digitized spectra, is able to automatically select ELGs candidates. Density to intensity transformation has not been used in our method; the detection of the emission is performed applying three independent criteria over the one-dimensional spectra in raw data. The automatically selected sample is compared with that obtained after a careful visual scan. Spectroscopic observations at moderate spectral resolution are presented for the whole sample of candidates in order to study the drawbacks and the biases of both methods.