In a collaborative effort, researchers from various institutions, including the European Southern Observatory, the University of Massachusetts Amherst, and the National Astronomical Observatory of Japan, have conducted a comprehensive study of the galaxy HZ10, located at a high redshift of z=5.65. This research, published in the Astrophysical Journal, aims to understand the assembly of galaxies in the early universe by examining their stellar, gas, and dust contents.
The team utilized the Atacama Large Millimeter/submillimeter Array (ALMA) and the James Webb Space Telescope (JWST) to observe HZ10 across multiple wavelengths. They combined new ALMA Band 10 and Band 4 observations with previously taken ALMA Band 6 through 9 data to constrain the galaxy’s dust properties. Additionally, they used archival high-resolution [CII] observations to estimate the galaxy’s dynamical mass and molecular and atomic gas mass, along with JWST measurements of metallicity and stellar mass.
The researchers detected continuum emission from HZ10 in Bands 10 and 4 at the 3.4-4.0σ level, allowing them to measure a dust temperature of 37 K and a dust mass of approximately 10^8 solar masses. By leveraging the dynamical constraints, they inferred the total gas budget of HZ10 and found that commonly used [CII]-to-H2 and [CII]-to-HI conversions overpredict the gas mass relative to the dynamical mass. Consequently, they derived a [CII]-to-total interstellar medium (ISM) mass (atomic + molecular) conversion factor specific to HZ10, which corresponds to 39 M☉ L☉^-1.
The study also revealed that HZ10 falls below the local scaling relation between dust-to-gas ratio and metallicity, suggesting inefficient ISM dust growth. These findings demonstrate the powerful synergy between ALMA and JWST in disentangling the baryonic components of early galaxies, paving the way for future studies of larger samples.
For the energy sector, this research highlights the importance of understanding the composition and evolution of galaxies, which can provide insights into the origins of various energy sources. By studying the interstellar medium and its components, researchers can better understand the processes that lead to the formation of stars and planets, ultimately contributing to our knowledge of the universe’s energy dynamics. Additionally, the advanced observational techniques and data analysis methods developed for this study can be applied to other areas of astrophysics and energy research.
This article is based on research available at arXiv.