11/18/2023 0 Comments 2017 national hidata![]() H 2 further condenses and forms stars, which when evolve return the ISM with dust and gas (Kennicutt 1998 Krumholz 2012). Dust can act as a catalyst in the transformation from H I to H 2 gas and also plays an important role in balancing the heating and cooling processes of gas in a galaxy (Hollenbach & Salpeter 1971 Hollenbach & Tielens 1997). Through the process of star formation, the different components of ISM (H I, H 2, and dust) are tightly connected to each other. In spite of these difficulties, studies based on existing observations have shown a dynamic picture of ISM evolution and its link to galaxy evolution. ![]() Most of the observations have been conducted by space telescopes, such as IRAS (Neugebauer et al. Dust mass is dominated by large dust grains, but small dust grains provide useful diagnostics of ISM properties (Draine & Li 2007). Dust is typically observed in the infrared (IR) as dust grains absorb the light from stars and re-emit across the entire IR band. 2022), despite the uncertainty of conversion between CO and H 2 masses related to the metallicity, pressure, and radiation field (e.g., Schruba et al. CO observations have reached a higher redshift than H I (e.g., Daddi et al. The studies of H 2 are usually conducted by observing the CO emission, as done by the extended CO Legacy Database for GASS (xCOLD GASS Saintonge et al. But the majority of galaxies detected in these new surveys remain unresolved or marginally resolved (Koribalski et al. 2007, 2008) and the South African Meer-Karoo Array Telescope (MeerKAT Jonas & MeerKAT Team 2016). The situation is improved with SKA pathfinder surveys conducted at the Australian Square Kilometre Array Pathfinder (ASKAP Johnston et al. For H I gas, either the sample sizes are small and biased when the data are collected with interferometry, or the spatial resolution of data is low and only integral spectra can be obtained with single-dish telescopes (Saintonge & Catinella 2022). Such dependence highlights the caveat of using the W3 luminosity as an integral SFR indicator, and is consistent with findings of studies that target star-forming regions in more nearby galaxies and accurately derive dust masses based on mapping-mode spectroscopy.Ī comprehensive census of the multiphase interstellar medium (ISM) and its hydrodynamic processes can provide important insights into the understanding of galaxy evolution, despite the difficulties to observe them.Īt present, gathering statistically large samples of ISM (i.e., the atomic neutral hydrogen gas H I, the molecular hydrogen gas H 2, and the dust) properties remains challenging. ![]() Additionally, we find that at a given dust mass and star formation rate (SFR), the galactic Wide-field Infrared Explorer W3 luminosities show a significant dependence on the luminosity and the stellar mass surface density. The predicted dust masses show scaling relations consistent with fiducial ones in the literature, supporting their robustness. Based on the newly calibrated relationship between inner gas mass and dust mass, we predict dust masses for disk-dominated galaxies from the xCOLD GASS sample. It supports that dust is more closely associated with cospatial cold gas than the overall cold gas. We find that the inner gas-to-dust ratio is almost independent of gas-phase metallicity, and confirm that the inner gas mass (H I+H 2) shows a tighter relation with dust mass and monochromatic 500 μm luminosity than the integral gas mass. We select a disk-like galaxy sample with observations of the H I, H 2, and dust from the Herschel Reference Survey, and derive inner H I masses within the optical radius.
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