HerMES : SPIRE detection of high redshift massive compact galaxies in GOODS-N field

TL;DR

This study investigates the far-infrared properties of massive high-redshift galaxies in the GOODS-N field, revealing differences in star formation activity related to galaxy morphology using Herschel and Spitzer data.

Contribution

It provides new insights into the FIR emission and star formation rates of massive galaxies at z~2-3, highlighting morphological dependencies.

Findings

Disk-like galaxies are more easily detected at FIR wavelengths.

Star formation rates are significantly lower in spheroidal galaxies.

Disk galaxies exhibit higher specific star formation rates.

Abstract

We have analysed the rest-frame far infrared (FIR) properties of a sample of massive (Mstar > 10^11Msun) galaxies at 2<z<3 in the GOODS (Great Observatories Origins Deep Survey) North field using the Spectral and Photometric Imaging Receiver (SPIRE) instrument aboard the Herschel Space Observatory. To conduct this analysis we take advantage of the data from the HerMES key program. The sample comprises 45 massive galaxies with structural parameters characterised with HST NICMOS-3. We study detections at submm Herschel bands, together with Spitzer 24{\mu}m data, as a function of the morphological type, mass and size. We find that 26/45 sources are detected at MIPS-24{\mu}m and 15/45 (all MIPS-24{\mu}m detections) are detected at SPIRE-250{\mu}m, with disk-like galaxies more easily detected. We derive star formation rates (SFR) and specific star formation rates (sSFR) by fitting the spectral energy distribution (SED) of our sources, taking into account non-detections for SPIRE and systematic effects for MIPS derived quantities. We find that the mean SFR for the spheroidal galaxies (50-100 Msun*yr^-1) is substantially (a factor ~ 3) lower than the mean value presented by disk-like galaxies (250-300 Msun*yr^-1).