Spectroscopic Observations of \delta Sco Through the 2011 Periastron Passage

Abstract

We present prelimiary results from a coordinated spectroscopic campaign in 2011, centered on the \delta Sco periastron passage in July. Data have mostly been obtained with the FEROS/2.2 m at La Silla and ESPaDOnS/CFHT at Mauna Kea echelle instruments. Main results include the absence of tidally induced disturbance to the main \beta Cephei pulsation mode and the absence of tidally triggered mass-ejection at time of periastron proper. The observed (as far as yet analyzed) variations are compatible with the picture of a disk that is disturbed on its outer radius, with the disturbance propagating inwards after the periastron.