The ALMA-QUARKS Survey. IV. Core Mass Function and Evolutionary Trends in Core Formation Efficiency and Chemistry

The ALMA-QUARKS (Querying Underlying Mechanisms of Massive Star Formation with ALMA-Resolved Gas Kinematics and Structures) survey targets 139 massive protoclusters selected from the ATOMS survey. The targets were observed at 1.3 mm wavelength with an angular resolution of about0.3, corresponding to about10 cubed au at the sample's median distance of about3.8 kpc. Using getsf, we identify 3374 dense cores and classify them as starless, protostellar, hot core, or H ii region candidates based on spectral-line diagnostics (e.g., H30 α, CH 3 CN, and CH 3 OH) and CO outflow associations. The resulting catalog provides core physical properties and enables statistical investigations of dense core populations in massive protocluster environments. The derived global core mass function (CMF) after excluding H ii region candidates, which is biased by distance effects, has a relatively flat power-law slope at the high-mass end (dN/d M proportional to M-γ, with γ=0.98 plus or minus0.03). In contrast, the measured high-mass slopes in individual distance bins are approximately Salpeter-like, while their fitted lower mass limits increase with distance. We further examine the core formation efficiency (CFE) across the full sample and find that it positively correlates with the luminosity-to-mass ratio of the parental clumps, consistent with an evolutionary increase in the fraction of mass concentrated into dense cores. We also investigate the detection rates of different molecular tracers and find systematic chemical variations with evolutionary stage. Compared with the ASHES survey, we find that the detection rates of deuterated species vary significantly even for cores at the same evolutionary stages, suggesting an important environmental influence on the chemical evolution of cores.