Candidates for giant lobes projecting from the LBV stars P Cygni and R 143

Abstract

Received ; accepted Abstract. Deep, wide-field, continuum-subtracted, images in the light of the H� + (N ii) 6548 & 6584 u and (O iii)5007 u nebular emission lines have been obtained of the environment of the Luminous Blue Variable (LBV) star P Cygni. A previously discovered, receding, nebulous filament along PA 50 ◦ has now been shown to extend up to 12 ' from this star. Furthermore, in the light of (O iii)5007 u a southern counterpart is discovered as well as irregular filaments on the opposite side of P Cygni. Line profiles from this nebulous complex indicate that this extended nebulosity is similar to that associated with middle-aged supernova remnants. However, there are several indications that it has originated in P Cygni and is not just a chance superposition along the same sight-line. This possibility is explored here and comparison is made with a new image of the LBV star R 143 in the LMC from which similar filaments appear to project. The dynamical age of the P Cygni giant lobe of � 5×10 4 yr is consistent with both the predicted and observed durations of the LBV phases of 50 M⊙ stars after they have left the main sequence. Its irregular shape may have been determined by the cavity formed in the ambient gas by the energetic wind of the star, and shaped by a dense torus, when on the main sequence. The proper motion and radial velocity of P Cygni, with respect to its local environment, could explain the observed angular and kinematical shifts of the star compared with the giant lobe.