Symbiotic stars: molecular emission bands in circumstellar medium

MARCHIANO, P.; ARIAS, M. L.; CIDALE, L.; BORGES FERNANDES, M.; KRAUS, M.

Córdoba

Conferencia; 57° Reunión Anual de la Asociación Argentina de Astronomía; 2014

Observatorio Astronómico de Córdoba

Symbiotic stars are thought to be the progenitors of Type Ia supernovae. They are interacting binaries consisting of a cool giant and a hot, luminous object, typically a white dwarf. These systems are embedded in dense circumstellar material, which results from previous interaction phases and often display a complex and diverse structure (bipolar-lobes, jets, ionized and neutral nebulae, and circumstellar disks). The study of the molecular composition of the disks is crucial for our understanding of its formation history. So far, CO band emission was detected only sparsely (e.g. from BI CRU [1]), while recent observations revealed simultaneous, strong SiO and water maser emission from several systems [2]. We analyze a sample of symbiotic objects in the near-infrared using OSIRIS at the SOAR Telescope to search for molecular band emission from CO. In this contribution we present our first set of data in the K-band.