Far-Infrared and submillimeter properties of SDSS galaxies in the Herschel ATLAS science demonstration phase field

TL;DR

This study analyzes the far-infrared and submillimeter properties of SDSS galaxies using Herschel data, revealing correlations with morphology, spectral type, and star formation indicators, and highlighting limitations of single-band observations.

Contribution

It provides a detailed analysis of galaxy properties across multiple wavelengths and morphological types, emphasizing the complexity of using single Herschel bands to trace star formation.

Findings

Peculiar galaxies have higher luminosity-to-mass ratios.

Correlation between far-infrared/submillimeter and H-alpha luminosities weakens at longer wavelengths.

Single Herschel SPIRE band is insufficient for accurate star formation tracing.

Abstract

Using the Herschel ATLAS science demonstration phase data crossidentified with SDSS DR7 spectra, we select 297 galaxies with F250{\mu}m > 5{\sigma}. The sample galaxies are classified into five morphological types, and more than 40% of the galaxies are peculiar/compact galaxies. The peculiar galaxies show higher far-infrared/submillimeter luminosity-to-mass ratios than the other types. We perform and analyze the correlations of far-infrared/submillimeter and H{\alpha} luminosities for different morphological types and different spectral types. The Spearman rank coefficient decreases and the scatter increases with the wavelength increasing from 100 {\mu}m to 500 {\mu}m. We conclude that a single Herschel SPIRE band is not good for tracing star formation activities in galaxies. AGNs contribute less to the far-infrared/submillimeter luminosities and do not show a difference from star-forming galaxies. However, the earlier type galaxies present significant deviations from the best fit of star-forming galaxies.