TY - JOUR
T1 - ALMA Lensing Cluster Survey
T2 - A spectral stacking analysis of [C II] in lensed z similar to 6 galaxies
AU - Jolly, Jean-Baptiste
AU - Knudsen, Kirsten
AU - Laporte, Nicolas
AU - Richard, Johan
AU - Fujimoto, Seiji
AU - Kohno, Kotaro
AU - Ao, Yiping
AU - Bauer, Franz E.
AU - Egami, Eiichi
AU - Espada, Daniel
AU - Dessauges-Zavadsky, Miroslava
AU - Magdis, Georgios
AU - Schaerer, Daniel
AU - Sun, Fengwu
AU - Valentino, Francesco
AU - Wang, Wei-Hao
AU - Zitrin, Adi
PY - 2021/8/23
Y1 - 2021/8/23
N2 - Context. The properties of galaxies at redshift z>6 hold the key to our understanding of the early stages of galaxy evolution and can potentially identify the sources of the ultraviolet radiation that give rise to the epoch of reionisation. The far-infrared cooling line of [C II] at 158 mu m is known to be bright and correlate with the star formation rate (SFR) of low-redshift galaxies, and hence is also suggested to be an important tracer of star formation and interstellar medium properties for very high-redshift galaxies.Aims. With the aim to study the interstellar medium properties of gravitationally lensed galaxies at z>6, we search for [C II] and thermal dust emission in a sample of 52 > 6 galaxies observed by the ALMA Lensing Cluster Survey.Methods. We perform our analysis using LINESTACKER, stacking both [C II] and continuum emission. The target sample is selected from multiple catalogues, and the sample galaxies have spectroscopic redshift or low-uncertainty photometric redshifts (sigma(z)Results. Our analyses find no detection of either [C II] or continuum. An upper limit on L-[CII] is derived, implying that [C II] remains marginally consistent for low-SFR z>6 galaxies but likely is under-luminous compared to the local L-[CII]-SFR relationship. We discuss potential biases and possible physical effects that may be the cause of the non-detection. Further, the upper limit on the dust continuum implies that less than half of the star formation is obscured.
AB - Context. The properties of galaxies at redshift z>6 hold the key to our understanding of the early stages of galaxy evolution and can potentially identify the sources of the ultraviolet radiation that give rise to the epoch of reionisation. The far-infrared cooling line of [C II] at 158 mu m is known to be bright and correlate with the star formation rate (SFR) of low-redshift galaxies, and hence is also suggested to be an important tracer of star formation and interstellar medium properties for very high-redshift galaxies.Aims. With the aim to study the interstellar medium properties of gravitationally lensed galaxies at z>6, we search for [C II] and thermal dust emission in a sample of 52 > 6 galaxies observed by the ALMA Lensing Cluster Survey.Methods. We perform our analysis using LINESTACKER, stacking both [C II] and continuum emission. The target sample is selected from multiple catalogues, and the sample galaxies have spectroscopic redshift or low-uncertainty photometric redshifts (sigma(z)Results. Our analyses find no detection of either [C II] or continuum. An upper limit on L-[CII] is derived, implying that [C II] remains marginally consistent for low-SFR z>6 galaxies but likely is under-luminous compared to the local L-[CII]-SFR relationship. We discuss potential biases and possible physical effects that may be the cause of the non-detection. Further, the upper limit on the dust continuum implies that less than half of the star formation is obscured.
KW - galaxies: formation
KW - galaxies: statistics
KW - galaxies: high-redshift
KW - radio lines: galaxies
KW - galaxies: evolution galaxies: star formation
KW - STAR-FORMING GALAXIES
KW - ULTRA-DEEP FIELD
KW - REST-FRAME PROPERTIES
KW - LYMAN-BREAK GALAXIES
KW - LY-ALPHA-EMITTERS
KW - MU-M EMISSION
KW - FRONTIER-FIELDS
KW - COSMIC REIONIZATION
KW - MOLECULAR GAS
KW - MULTIWAVELENGTH PHOTOMETRY
U2 - 10.1051/0004-6361/202140878
DO - 10.1051/0004-6361/202140878
M3 - Journal article
VL - 652
JO - Astronomy & Astrophysics
JF - Astronomy & Astrophysics
SN - 0004-6361
M1 - A128
ER -