2016ApJ...833..286H

We present a detailed modeling of the two broad bands observed at 6825 and 7082 Å in Sanduleak's star, a controversial object in the Large Magellanic Cloud. These bands are known to originate from Raman scattering of O VI λλ 1032 and 1038 photons with atomic hydrogen and are only observed in bona fide symbiotic stars. Our high-resolution spectrum obtained with the Magellan Inamori Kyocera Echelle spectrograph at the Magellan-Clay Telescope reveals, quite surprisingly, that the profiles of the two bands look very different: while the Raman 6825 A band shows a single broad profile with a redward extended bump, the Raman 7082 A band exhibits a distinct triple-peak profile. Our model suggests that the O vi emission nebula can be decomposed into a red, blue, and central emission region from an accretion disk, a bipolar outflow, and a further compact, optically thick region. We also perform Monte Carlo simulations with the aim of fitting the observed flux ratio F(6825)/F(7082) ∼ 4.5, which indicates that the neutral region in Sanduleak's star is characterized by the column density N_H i_ ∼ 1 x 10²³ cm^–2.