Bipolar jet growth and decline in Hen 3-1341: a direct link to fast wind and outburst evolution★

Abstract

We report on and investigate the evolution and disappearance in the symbiotic star Hen 3-1341 of collimated bipolar jets, which take the form of symmetrically displaced components of emission lines. From modelling of the emission-line spectrum it turns out that the accreting white dwarf (WD) in quiescence has T WD ∼ 1.2 x 10 5 K and R WD ∼ 0.14 R ○. , for a luminosity of 3.8 x 10 3 L ○. , and it is stably burning hydrogen on the surface at a rate of M H ∼ 5 x 10 -8 M ○. yr -1 , feeding ionizing photons to a radiation bounded circumstellar nebula extending for ∼17 au. The WD underwent a multimaxima outburst lasting from 1998 to 2004 during which its H-burning envelope reacted to a probable small increase in the mass accretion by expanding and cooling to T eff ∼ 1 x 10 4 K and R ∼ 20 R ○. , mimicking an A-type giant that radiated a total of ∼6 x 10 44 erg, at an average rate of ∼1 × 10 3 L ○. . Bipolar jets developed at the time of outburst maximum and their strength declined in parallel with the demise of the fast wind from the inflated WD, finally disappearing when the wind stopped halfway to quiescence, marking a 1:1 correspondence between jets presence and feeding action of the fast wind. The total mass in the jets was M jet ∼ 2.5 x 10 -7 M ○. for a kinetic energy of E kin jet ∼ 1.7 x 10 42 (sin i) -1 erg, corresponding to ∼0.3(sin i) -1 per cent of the energy radiated during the whole outburst. We suggest that the spectroscopic search for jets in symbiotic stars could pay higher dividends if focused on the outburst phases characterized by maximum wind intensity.