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arXiv · 1001.3892

On the multiplicity of the zero-age main-sequence O star Herschel 36

Julia I. Arias·Rodolfo H. Barba·Roberto C. Gamen·Nidia I. Morrell·Jesus Maiz Apellaniz·Emilio J. Alfaro·Alfredo Sota·Nolan R. Walborn·Christian Moni Bidin
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Abstract

We present the analysis of high-resolution optical spectroscopic observations of the zero-age main-sequence O star Herschel 36 spanning six years. This star is definitely a multiple system, with at least three components detected in its spectrum. Based on our radial-velocity (RV) study, we propose a picture of a close massive binary and a more distant companion, most probably in wide orbit about each other. The orbital solution for the binary, whose components we identify as O9 V and B0.5 V, is characterized by a period of 1.5415 +/- 0.0006 days. With a spectral type O7.5 V, the third body is the most luminous component of the system and also presents RV variations with a period close to 498 days. Some possible hypotheses to explain the variability are briefly addressed and further observations are suggested.

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Julia I. Arias, Rodolfo H. Barba, Roberto C. Gamen, Nidia I. Morrell, Jesus Maiz Apellaniz, Emilio J. Alfaro, Alfredo Sota, Nolan R. Walborn, Christian Moni Bidin. 2010-01-21. On the multiplicity of the zero-age main-sequence O star Herschel 36. https://doi.org/10.1088/2041-8205%2F710%2F1%2Fl30

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