AN OBSERVATIONAL INVESTIGATION OF THE IDENTITY OF B11244 (l-C3H+/C3H-)

作者：McGuire Brett A^*; Carroll P Brandon; Gratier Pierre; Guzman Viviana; Pety Jerome; Roueff Evelyne; Gerin Maryvonne; Blake Geoffrey A; Remijan Anthony J

来源：Astrophysical Journal, 2014, 783(1): 36.

DOI：10.1088/0004-637X/783/1/36

• astrochemistry
• ISM: clouds
• ISM: individual objects (Sagittarius B2(N), TMC-1, Horsehead PDR, IRC+10216)
• ISM: molecules

Pety et al. have reported the detection of eight transitions of a closed-shell, linear molecule (B11244) in observations toward the Horsehead photodissociation region (PDR), which they attribute to the l-C3H+ cation. Recent high-level ab initio calculations have called this assignment into question; the anionic C3H- molecule has been suggested as a more likely candidate. Here, we examine observations of the Horsehead PDR, Sgr B2(N), TMC-1, and IRC+10216 in the context of both l-C3H+ and C3H-. We find no observational evidence of K-a = 1 lines, which should be present were the carrier indeed C3H-. Additionally, we find a strong anticorrelation between the presence of known molecular anions and B11244 in these regions. Finally, we discuss the formation and destruction chemistry of C3H- in the context of the physical conditions in the regions. Based on these results, we conclude there is little evidence to support the claim that the carrier is C3H-.

• 出版日期2014-3-1