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GCIRS16SW: a massive eclipsing binary in the Galactic Center

F. Martins·S. Trippe·T. Paumard·T. Ott·R. Genzel·G. Rauw·F. Eisenhauer·S. Gillessen·H. Maness·R. Abuter
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Abstract

We report on the spectroscopic monitoring of GCIRS16SW, an Ofpe/WN9 star and LBV candidate in the central parsec of the Galaxy. SINFONI observations show strong daily spectroscopic changes in the K band. Radial velocities are derived from the HeI 2.112 um line complex and vary regularly with a period of 19.45 days, indicating that the star is most likely an eclipsing binary. Under various assumptions, we are able to derive a mass of ~ 50 Msun for each component.

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F. Martins, S. Trippe, T. Paumard, T. Ott, R. Genzel, G. Rauw, F. Eisenhauer, S. Gillessen, H. Maness, R. Abuter. 2006-08-10. GCIRS16SW: a massive eclipsing binary in the Galactic Center. https://doi.org/10.1086/508328

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