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

TL;DR

This study analyzes photometric data of the symbiotic star MWC 560 from 1990 to 2023, estimating its luminosity and mass accretion rate, and identifying the threshold where optical flickering ceases.

Contribution

It provides the first long-term estimate of the luminosity and accretion rate of MWC 560, revealing the relationship between accretion rate and flickering behavior.

Findings

Luminosity varies from 200 to 3000 solar luminosities.

Mass accretion rate ranges from 1e-7 to 2e-6 solar masses per year.

Optical flickering disappears at accretion rates above 1e-6 solar masses per year.

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.