Revisiting the Hubble sequence in the SDSS DR7 spectroscopic sample: a publicly available Bayesian automated classification
Abstract
We present an automated morphological classification in 4 types (E, S0, Sab, Scd) of ~700 000 galaxies from the SDSS DR7 spectroscopic sample based on support vector machines. The main new property of the classification is that we associate a probability to each galaxy of being in the four morphological classes instead of assigning a single class. The classification is therefore better adapted to nature where we expect a continuous transition between different morphological types. The algorithm is trained with a visual classification and then compared to several independent visual classifications including the Galaxy Zoo first-release catalog. We find a very good correlation between the automated classification and classical visual ones. The compiled catalog is intended for use in different applications and is therefore freely available through a dedicated webpage* and soon from the CasJobs database.
Full catalog is only available in electronic form at CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/525/A157 or via http://gepicom04.obspm.fr/sdss_morphology/Morphology_2010.html- Publication:
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Astronomy and Astrophysics
- Pub Date:
- January 2011
- DOI:
- 10.1051/0004-6361/201015735
- arXiv:
- arXiv:1010.3018
- Bibcode:
- 2011A&A...525A.157H
- Keywords:
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- catalogs;
- astronomical databases: miscellaneous;
- Galaxy: fundamental parameters;
- galaxies: evolution;
- Galaxy: formation;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - Instrumentation and Methods for Astrophysics
- E-Print:
- A&