Overdensity of SubMillimiter Galaxies in the GJ526 Field mapped with the NIKA2 Camera

TL;DR

This study used the NIKA2 camera to map a large field around GJ526, revealing an overdensity of submillimeter galaxies likely forming a high-redshift cosmic filament, advancing understanding of galaxy distribution.

Contribution

First detailed millimeter-wave mapping of the GJ526 field showing a potential high-redshift filament of dusty galaxies, based on new NIKA2 observations.

Findings

Detected an overdensity of SMGs along a filament-like structure.

Confirmed the presence of additional sources compared to previous observations.

Suggested the structure might be a high-redshift cosmic filament.

Abstract

Using the NIKA2 dual band millimeter camera installed on the IRAM30m telescope, we have mapped a relatively large field (~70 arcmin^2) in the direction of the star GJ526 to investigate the nature of the sources found with the MAMBO camera at 1.2 mm ten years earlier. We have found that they must be dust-obscured galaxies (SMGs) in the background beyond the star. The new NIKA2 map at 1.15 mm reveals additional sources and, in fact, an overdensity of SMGs predominantly distributed along a filament-like structure in projection on the sky across the whole observed field. We speculate this might be a cosmic filament at high redshift as revealed in cosmological hydrodynamical simulations. Measurement of spectroscopic redshifts of the SMGs in the candidate filament is required now for a definitive confirmation of the nature of the structure.