Orientation effect on the ligh curve shape of periodic methanol maser sources

Autor: Morgan, J., van der Walt, D. J., Chibueze, J. O., Zhang, Q.
Rok vydání: 2021
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1093/mnras/stab2185
Popis: We report the results of our pilot millimeter observations of periodic maser sources. Using SMA, we carried out 1.3\,mm observations of G22.357$+$0.066 and G25.411$+$0.105, while ALMA 1.3 mm archival data was used in the case of G9.62+0.19E. Two continuum cores (MM1 and MM2) were detected in G22.357$+$0.066, while 3 cores (MM1 -- MM3) detected in G25.411$+$0.105. Assuming dust-to-gas ratio of 100, we derived the masses of the detected cores. Using the $^{12}$CO (2-1) and $^{13}$CO (2-1) line emission, we observed gas kinematics tracing the presence of bipolar outflows in all three star-forming regions. In the cases of G22.357$+$0.066 and G9.62+0.19E, both with similar periodic maser light curve profiles, the outflowing gas is seen in the north-west south-east direction. This suggest edge-on view of the 2 sources. G25.411$+$0.105, with a contrasting light curve profile, show a spatially co-located blue and red outflow lobes, suggesting a face-on view. Our results suggest that orientation effects may play a role in determining the characteristics of the light curves of periodic methanol masers.
Comment: 12 pages, 12 figures; Accepted for publication in MNRAS
Databáze: arXiv