Template-based classification of SDSS-GALEX point sources

Title

Template-based classification of SDSS-GALEX point sources

Creator

Anjum A.; Das M.; Murthy J.; Gudennavar S.B.; Gopal R.; Bubbly S.G.

Description

We have classified a sample of 37,492 objects from SDSS into QSOs, galaxies and stars using photometric data over five wave bands (u, g, r, i and z) and UV GALEX data over two wave bands (near-UV and far-UV) based on a template fitting method. The advantage of this method of classification is that it does not require any spectroscopic data and hence the objects for which spectroscopic data is not available can also be studied using this technique. In this study, we have found that our method is consistent by spectroscopic methods given that their UV information is available. Our study shows that the UV colours are especially important for separating quasars and stars, as well as spiral and starburst galaxies. Thus it is evident that the UV bands play a crucial role in the classification and characterization of astronomical objects that emit over a wide range of wavelengths, but especially for those that are bright at UV. We have achieved the efficiency of 89% for the QSOs, 63% for the galaxies and 84% for the stars. This classification is also found to be in agreement with the emission line diagnostic diagrams. 2018, Indian Academy of Sciences.

Source

Journal of Astrophysics and Astronomy, Vol-39, No. 5

Date

2018-01-01

Publisher

Springer

Subject

photometric classification; point-sources; QSOs; SDSS-GALEX; SED fitting; UV-optical photometry

Coverage

Anjum A., Department of Physics and Electronics, CHRIST (Deemed to be University), Bengaluru, 560 029, India; Das M., Indian Institute of Astrophysics, II Block, Kormamangala, Bengaluru, 560 034, India; Murthy J., Indian Institute of Astrophysics, II Block, Kormamangala, Bengaluru, 560 034, India; Gudennavar S.B., Department of Physics and Electronics, CHRIST (Deemed to be University), Bengaluru, 560 029, India; Gopal R., Department of Physics, CMR Institute of Technology, Bengaluru, 560 037, India; Bubbly S.G., Department of Physics and Electronics, CHRIST (Deemed to be University), Bengaluru, 560 029, India

Rights

Restricted Access

Relation

ISSN: 2506335

Format

Online

Language

English

Type

Article

Identifier

https://doi.org/10.1007/s12036-018-9552-3

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85053881028&doi=10.1007%2fs12036-018-9552-3&partnerID=40&md5=b4ede5abebb6aeb4486002b94e059d3f