# A bias in optical observations of high redshift luminous infrared galaxies

**Authors:** V. Charmandaris, E. Le Floc'h, I. F. Mirabel  
**arXiv:** [astro-ph/0311632](https://arxiv.org/abs/astro-ph/0311632)  
**Date:** 2003-11-28  
**Summary page:** https://www.summarizepaper.com/en/paper/astro-ph--0311632v1/

## Key points

- The paper presents evidence for significant differences in morphology between rest frame UV and 7micron mid-IR emission of two nearby violently interacting infrared luminous galaxies (LIRGs), VV114 and Arp299.
- Nearly all LIRGs are interacting systems and it is currently accepted that they dominate the IR emission at z>1.
- Luminous IR galaxies located at z=1-2 could easily be detected as unresolved sources in deep optical/near-IR ground-based surveys, as well as upcoming 24micron surveys with the Space Infrared Telescope Facility.
- The spatial resolution of these surveys will result in blending of the emission from unresolved interacting components, leading to a systematic underestimation of their dust content when observed optically.
- This paper highlights a potential bias in current observations of high redshift LIRGs due to limitations in observational techniques and emphasizes the importance of considering morphological differences when interpreting observations of LIRGs.
- It also highlights the need for improved observational techniques to accurately measure their properties.

## Summary

The paper "A bias in optical observations of high redshift luminous infrared galaxies" presents evidence for the significant differences in morphology between the rest frame UV and 7micron mid-IR emission of two nearby violently interacting infrared luminous galaxies (LIRGs), VV114 and Arp299. The authors note that nearly all LIRGs are interacting systems and it is currently accepted that they dominate the IR emission at z>1. However, luminous IR galaxies located at z=1-2 could easily be detected as unresolved sources in deep optical/near-IR ground-based surveys, as well as upcoming 24micron surveys with the Space Infrared Telescope Facility. The authors demonstrate that the spatial resolution of these surveys will result in blending of the emission from unresolved interacting components, leading to a systematic underestimation of their dust content when observed optically. This paper highlights a potential bias in current observations of high redshift LIRGs due to limitations in observational techniques and emphasizes the importance of considering morphological differences when interpreting observations of LIRGs. It also highlights the need for improved observational techniques to accurately measure their properties.