From Stellar Nurseries To Old Stellar Populations: a Multiwavelength Case of Ngc 1055

Abstract

Given the complex nature of galaxies' interstellar medium (ISM), multiwavelength data are required to probe the interplay among gas, dust, and stellar populations. Spiral galaxies are ideal laboratories for such a goal as they are rich in gas and dust. Using carbon monoxide (CO) along with GALEX far-ultraviolet (FUV) and Spitzer near-infrared (NIR) data we probe the correlations amongst the properties of stellar populations, gas, and dust over the disc of the spiral galaxy NGC 1055 at multiple angular resolutions, that is, 2, 4, and 17 arcsec corresponding to a linear size of 144, 288, and 1.2 kpc, respectively. Our results indicate an asymmetry in the physical conditions along the galaxy's disc, that is, the gas is slightly more extended and brighter, and molecular gas mass is higher on the disc's eastern side than the western side. All physical properties (i.e. molecular gas mass, CO line ratios, stellar mass, and NIR emission) decrease from the centre going outwards in the disc with some exceptions (i.e. the extinction, FUV radiation, and the [3.6]-[4.5] colour). Our analysis indicates that the colour gets bluer (metallicity increases) halfway through the disc, then redder (metallicity decreases) going outwards further in the disc.