2024/05/22 by Chunyi Zhang, Junfeng Wang, Zhang, Chunyi +9 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena
paper · pdf · doi:10.48550/arxiv.2405.13284
openalex publication_date 2024/05/22 · openalex created_date 2024/05/25 · openalex updated_date 2026/07/28
Based on the newly acquired dense gas observations from the JCMT MALATANG survey and X-ray data from Chandra, we explore the correlation between hot gas and HCN J=4 → 3, HCO+ J=4 → 3 emission for the first time at sub-kiloparsec scale of five nearby star-forming galaxies, namely M82, M83, IC 342, NGC 253, and NGC 6946. We find that both HCN J=4 → 3 and HCO+ J=4 → 3 line luminosity show a statistically significant correlation with the 0.5-2 keV X-ray emission of the diffuse hot gas (L\rm 0.5 - 2 keV\rm gas). The Bayesian regression analysis gives the best fit of \rm log(L\rm 0.5-2 keV\rm gas /\rm erg s-1)=2.39 \rm log(L'\rm HCN(4-3) /\rm K km s-1 pc2)+24.83 and \rm log(L\rm 0.5-2 keV\rm gas /\rm erg s-1)=2.48 \rm log(L'\rm HCO+(4-3) /\rm K km s-1 pc2)+23.84, with dispersion of \thicksim0.69 dex and 0.54 dex, respectively. At the sub-kiloparsec scale, we find that the power-law index of the L\rm 0.5 - 2 keV\rm gas - star formation rate (SFR) relation is \rm log(L\rm 0.5-2 keV\rm gas /\rm erg s-1)=1.80 \rm log (\rm SFR /M_\odot \rm yr-1)+39.16, deviated from previous linear relations at global scale. This implies that the global property of hot gas significantly differs from individual resolved regions, which is influenced by the local physical conditions close to the sites of star formation.