2 papers
astro-ph.GA2025
The Chemical Clock of High-mass Star-forming Regions: N2H+/CCS
J. L. Chen, J. S. Zhang, J. X. Ge +6
Using the IRAM 30 m telescope, we presented observations of N2H+ J = 1-0, CCS JN = 87-76 and 77-66 lines toward a large sample of ultracompact HII regions (UC HIIs). Among our 88 U…
astro-ph.GA2024
Interstellar Nitrogen Isotope Ratios: Measurements on tracers of CN and CN
J. L. Chen, J. S. Zhang, C. Henkel +6
The nitrogen isotope ratio 14N/15N is a powerful tool to trace Galactic stellar nucleosynthesis and constraining Galactic chemical evolution. Previous observations have found lower…