Results of the summarizing process for the arXiv paper: 1804.03482v1

This study focuses on the main sequence (MS) of star-forming galaxies in deep far-infrared (FIR) cosmological surveys. These surveys are often affected by source confusion, which makes it challenging to examine the properties of individual galaxies accurately. To address this limitation, the authors of this study utilize the latest de-blended Herschel photometry, which reaches approximately 10 times deeper than the 5σ confusion limit in SPIRE. This enables more reliable measurements of star formation rates (SFRs), especially for fainter galaxies, and consequently a more accurate determination of the MS. The researchers develop a pipeline that combines the spectral energy distribution (SED) modeling and fitting tool CIGALE with the de-blending tool XID+. They generate flux density priors in the Herschel SPIRE bands using CIGALE and then use XID+ to extract flux densities from SPIRE maps. By combining these extracted flux densities with multi-wavelength data, they constrain SEDs and derive stellar mass (M*) and SFRs. Using these M* and SFR values, they populate the SFR-M* plane over a redshift range of 0.2 ≤ z < 6.0. The analysis reveals no significant evidence of a high-mass turn-over in the MS. Instead, they find that a simple two-parameter power law model best fits their data: log(SFR) = α[log(M*) - 10.5] + β.

• Study focuses on the main sequence (MS) of star-forming galaxies in deep far-infrared (FIR) cosmological surveys
• Source confusion is a challenge in accurately examining individual galaxy properties
• Latest de-blended Herschel photometry used to address source confusion limitation
• De-blending tool XID+ and SED modeling tool CIGALE combined to generate flux density priors and extract flux densities from SPIRE maps
• SEDs, stellar mass (M*), and star formation rates (SFRs) derived using extracted flux densities and multi-wavelength data
• SFR-M* plane populated over redshift range of 0.2 ≤ z < 6.0
• No significant evidence of high-mass turn-over in the MS found
• Simple two-parameter power law model best fits the data: log(SFR) = α[log(M*) - 10.5] + β

Exploring the Main Sequence of Star-Forming Galaxies in Deep Far-Infrared Cosmological Surveys

Deep far-infrared (FIR) cosmological surveys are a powerful tool for studying star formation in galaxies. However, source confusion can make it difficult to accurately measure the properties of individual galaxies. To address this limitation, researchers have developed a pipeline that combines two tools: CIGALE and XID+. This pipeline enables more reliable measurements of star formation rates (SFRs), especially for fainter galaxies, and consequently a more accurate determination of the main sequence (MS).

What is the Main Sequence?

The MS is an empirical relation between stellar mass (M*) and SFR. It describes how much stars form in a galaxy as a function of its total stellar mass. The MS has been studied extensively over different redshift ranges using various techniques such as optical spectroscopy and FIR photometry. In general, it is found that star formation increases with M* up to some characteristic mass before decreasing again at higher masses.

CIGALE & XID+

To explore the MS in deep FIR cosmological surveys, researchers utilized CIGALE and XID+. CIGALE stands for Code Investigating GALaxy Emission; it is an SED modeling and fitting tool used to derive physical parameters from multi-wavelength data such as M*, SFRs, dust attenuation etc.. On the other hand, XID+ is a de-blending tool used to extract flux densities from SPIRE maps which reach approximately 10 times deeper than the 5σ confusion limit in SPIRE bands. By combining these extracted flux densities with multi-wavelength data obtained by CIGALE, they were able to constrain SEDs and derive M* and SFR values over a redshift range of 0.2 ≤ z < 6.0 .

Results & Analysis

The analysis revealed no significant evidence of a high-mass turn-over in the MS; instead they found that a simple two parameter power law model best fits their data: log(SFR) = α[log(M*) - 10.5] + β . This suggests that there may be no upper limit on star formation rates at high masses or alternatively that any existing upper limits are too weak to be detected by current surveys due to observational limitations such as source confusion or limited depth/resolution etc.. The authors also note that their results agree well with previous studies conducted using optical spectroscopy or UV/optical imaging but disagree with those based on mid/far infrared observations which tend to show steeper slopes at high masses due to contamination from AGN activity or dust heating by old stars rather than young stars associated with ongoing star formation processes .

Conclusion

In conclusion , this study provides further evidence for understanding how galaxies populate the main sequence over different redshifts using deep far infrared cosmological surveys combined with advanced de-blending techniques like XID+ along with powerful modelling tools like CIGALE . The findings suggest that there may not be an upper limit on star formation rates at high masses though further research will need to be done before any definitive conclusions can be drawn about this topic .