THE RED RECTANGLE: ITS SHAPING MECHANISM AND ITS SOURCE OF ULTRAVIOLET PHOTONS

摘要: The proto planetary Red Rectangle (RR) nebula is powered by HD 44179, a spectroscopic binary (P = 318 d), in which luminous post-asymptotic giant branch (AGB) component the primary source of both luminosity and current mass loss. Here, we present results seven-year, eight-orbit monitoring program designed to uncover new information about Lyman/far-ultraviolet (far-UV) continuum system as well driving mechanism for bipolar outflow producing nebula. Our observations Hα line profile around orbital phase superior conjunction reveal secondary be origin fast (max. v ~ 560 km s–1) RR. was previously inferred on basis single, broad emission profile. variation total flux from central H II region with also identifies or its surroundings far-UV ionizing radiation system. estimated (~0.94 M ☉) speed suggest that this main-sequence star not white dwarf, suggested. We identify Lyman/far-UV hot, inner (T max ≥ 17,000 K) an accretion disk surrounding secondary, fed Roche lobe overflow post-AGB at rate 2-5 × 10–5 M ☉ yr–1. accretion-driven, found strongly modulated intercomponent separation highly eccentric (e 0.37) orbit, maximum speeds occurring near periastron minimum apastron. least 300 L ☉, 5% entire