RT Journal Article T1 Evidence of accretion triggered oscillations in the pre-main-sequence interacting binary AK Sco A1 Gómez de Castro, Ana Inés A1 López Santiago, Javier A1 Talavera, A. AB Pre-main sequence (PMS) binaries are surrounded by circumbinary disks from which matter falls onto both components. The material dragged from the circumbinary disk flows onto each star through independent streams channelled by the variable gravitational field. The action of the bar-like potential is most prominent in high eccentricity systems made of two equal mass stars. AK Sco is a unique PMS system composed of two F5 stars in an orbit with e=0.47. Henceforth, it is an ideal laboratory to study matter infall in binaries and its role in orbit circularization. In this letter, we report the detection of a 1.3mHz ultra low frequency oscillation in the ultraviolet light curve at periastron passage. This oscillation last 7 ks being most likely fed by the gravitational energy released when the streams tails spiralling onto each star get in contact at periastron passage enhancing the accretion flow; this unveils a new mechanism for angular momentum loss during pre-main sequence evolution and a new type of interacting binary. PB Wiley SN 0035-8711 YR 2013 FD 2013-02 LK https://hdl.handle.net/20.500.14352/33326 UL https://hdl.handle.net/20.500.14352/33326 LA eng NO Comunidad de Madrid NO Ministerio de Ciencia e Innovación (MICINN) DS Docta Complutense RD 30 abr 2024