Mass accretion rate in the jet-driving symbiotic binary MWC 560

Abstract

We analyze photometric observations of the symbiotic star MWC 560 in B and V bands obtained during the period 1990-2023. We estimate the luminosity and the mass accretion rate of the hot component. We find that the luminosity varies in the range from 200 $L_\odot$ to 3000 $L_\odot$, corresponding to a mass accretion rate in the range $1 \times 10^{-7} - 2 \times 10^{-6} \; M_\odot \; yr^{-1}$ (for a 0.9 $M_\odot$ white dwarf and distance 2217 pc). The optical flickering disappears at mass accretion rate of about $1\times 10^{-6}\; M_\odot \; yr^{-1}$, which sets an upper limit for the short-term variability from accreting white dwarf.