Proc. IAU volume 13, issue S336, P207-210 2017 DOI: 10.1017/s1743921317010225 View full text
Tomoya Hirota, Masahiro N. Machida, Yuko Matsushita, Kazuhito Motogi, Naoko Matsumoto, Mikyoung Kim, Ross A. Burns, Mareki Honma

Abstract: We present observational results of the submillimeter H2O and SiO lines toward a candidate high-mass young stellar object Orion Source I using ALMA. The spatial structures of the high excitation lines at lower-state energies of >2500 K show compact structures consistent with the circumstellar disk and/or base of the northeast-southwest bipolar outflow with a 100 au scale. The highest excitation transition, the SiO (v=4) line at band 8, has the most compact structure. In contrast, lower-excitation transitions …

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