Giants in the globular cluster ω Centauri: dust production, mass-loss and distance

Received date; accepted date We present spectral energy distribution modelling of 6875 stars in ω Centauri, obtaining stellar luminosities and temperatures by fitting literature photometry to stateof-the-art marcs stellar models. By comparison to four different sets of isochrones, we provide a new distance estimate to the cluster of 4850 ± 200 (random error) ±120 (systematic error) pc, a reddening of E(B − V) = 0.08 ± 0.02 (random) ±0.02 (systematic) mag and a differential reddening of ∆E(B − V) < 0.02 mag for an age of 12 Gyr. Several new post-early-AGB candidates are also found. Infra-red excesses of stars were used to measure total mass-loss rates for individual stars down to ∼ 7×10 −8 M⊙ yr−1. We find a total dust mass-loss rate from the cluster of 1.3 ± 0.8 0.5 ×10−9 M ⊙ yr−1, with the total gas mass-loss rate being> 1.2 ± 0.6 0.5 ×10−6 M ⊙ yr−1. Half of the cluster’s dust production and 30 % of its gas production comes from the two most extreme stars