2021/05/30 by Milan Sil, Satyam Srivastav, Bratati Bhat +10 · 1 citation
Physics and Astronomy · #Astro and Planetary Science #Astrochemistry #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Infrared #Interstellar cloud #Interstellar medium #Line (geometry) #Molecular cloud #Photodissociation #Radiative transfer #astro-ph.GA #astro-ph.SR
paper · pdf · doi:10.3847/1538-3881/ac09f9
44 pages, 28 figures, Accepted for the publication in The Astronomical Journal
arxiv created 2021/05/30 · openalex created_date 2021/06/22 · openalex publication_date 2021/08/25 · arxiv updated 2021/09/08 · openalex updated_date 2026/08/05
Abstract Phosphorus-related species are not known to be as omnipresent in space as hydrogen, carbon, nitrogen, oxygen, and sulfur-bearing species. Astronomers spotted very few P-bearing molecules in the interstellar medium and circumstellar envelopes. Limited discovery of the P-bearing species imposes severe constraints in modeling the P-chemistry. In this paper, we carry out extensive chemical models to follow the fate of P-bearing species in diffuse clouds, photon-dominated or photodissociation regions (PDRs), and hot cores/corinos. We notice a curious correlation between the abundances of PO and PN and atomic nitrogen. Since N atoms are more abundant in diffuse clouds and PDRs than in the hot core/corino region, PO/PN reflects <1 in diffuse clouds, ≪1 in PDRs, and >1 in the late warm-up evolutionary stage of the hot core/corino regions. During the end of the post-warm-up stage, we obtain PO/PN > 1 for hot core and <1 for its low-mass analog. We employ a radiative transfer model to investigate the transitions of some of the P-bearing species in diffuse cloud and hot core regions and estimate the line profiles. Our study estimates the required integration time to observe these transitions with ground-based and space-based telescopes. We also carry out quantum chemical computation of the infrared features of PH 3 , along with various impurities. We notice that SO 2 overlaps with the PH 3 bending-scissoring modes around ∼1000–1100 cm −1 . We also find that the presence of CO 2 can strongly influence the intensity of the stretching modes around ∼2400 cm −1 of PH 3 .