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"Optical Spectroscopy for the Star Formation Reference Survey (SFRS)"

Mr. Alexandros Maragoudakis
University of Crete, Greece
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When: Wednesday  May 15th  at 1:30 pm
Where: 2nd Floor Seminar Room

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Abstract:  

The Star Formation Reference Survey (SFRS) is a multi-wavelength project, studying the processes of star formation in the local Universe using a sample of 369 nearby galaxies.
We present the analysis of the optical spectra and the activity classification of the sample galaxies, based on optical emission-line diagnostics.
We develop a classification scheme taking into account both the uncertainties in emission-line ratios as well as the maximum starburst lines developed from evolution synthesis and photoionization models.
Furthermore, we examine the influence of aperture effects in the activity classification using two methods: 1) Different-sized long slit apertures, 2) Simulated elliptical apertures.
We find that there is a significant change in classification as we propagate from the nuclear regions to the integrated spectrum of the galaxies.
We also investigate the efficiency of starlight-subtraction methods to correct for these effects, and discuss possibilities to calibrate the correction applied to the line ratios.