Physical and Kinematical Characteristics of Wolf–Rayet Central Stars and their Host Planetary Nebulae

Abstract

We address the physical and kinematical properties of Wolf–Rayet [WR] central stars (CSs) and their host planetary nebulae (PNe). The studied sample comprises all [WR] CSs that are currently known. The analysis is based on recent observations of the parallax, proper motion, and color index of [WR] CSs from the Gaia space mission’s early third release (eDR3) catalog, as well as common nebular characteristics. The results revealed an evolutionary sequence, in terms of decreasing T eff, from the early hot [WO 1] to the late cold [WC 12] stars. This evolutionary sequence extends beyond [WR] CS temperature and luminosity to additional CS and nebular characteristics. The statistical analysis shows that the mean final stellar mass and evolutionary age of the [WR] CS sample are 0.595 ± 0.13 M ⊙ and 9449 ± 2437 yr, respectively, with a mean nebular dynamical age of 7270 ± 1380 yr. In addition, we recognize that the color of the majority (∼85%) of [WR] CSs tends to be red rather than their genuine blue color. The analysis indicates that two-thirds of the apparent red color of most [WR]s is attributed to the interstellar extinction whereas the other one-third is due to the PN self-extinction effect.