TY - JOUR
T1 - X-ray detection of astrospheres around three main-sequence stars and their mass-loss rates
AU - Kislyakova, Kristina
AU - Guedel, Manuel
AU - Koutroumpa, Dimitra
AU - Carter, Jennifer
AU - Lisse, Carey
AU - Saikia, Sudeshna Boro
N1 - Publisher Copyright:
© The Author(s), under exclusive licence to Springer Nature Limited 2024.
PY - 2024/5
Y1 - 2024/5
N2 - Stellar winds of cool main-sequence stars are difficult to constrain observationally. One way to measure stellar mass-loss rates is to detect the soft X-ray emission from stellar astrospheres produced by charge exchange between heavy ions of the stellar wind and cold neutrals of the interstellar medium surrounding the stars. Here we report detections of charge-exchange-induced X-ray emission from the extended astrospheres of three main-sequence stars, 70 Ophiuchi, ϵ Eridani and 61 Cygni, based on the analysis of XMM-Newton observations. We estimate the corresponding mass-loss rates to be 66.5 ± 11.1, 15.6 ± 4.4 and 9.6 ± 4.1 times the solar mass-loss rate for 70 Ophiuchi, ϵ Eridani and 61 Cygni, respectively, and compare our results with the alternative 'hydrogen wall' method. We also place upper limits on the mass-loss rates of several other main-sequence stars. This method has potential utility for determining the mass-loss rates from X-ray observations showing spatial extension beyond a coronal point source.
AB - Stellar winds of cool main-sequence stars are difficult to constrain observationally. One way to measure stellar mass-loss rates is to detect the soft X-ray emission from stellar astrospheres produced by charge exchange between heavy ions of the stellar wind and cold neutrals of the interstellar medium surrounding the stars. Here we report detections of charge-exchange-induced X-ray emission from the extended astrospheres of three main-sequence stars, 70 Ophiuchi, ϵ Eridani and 61 Cygni, based on the analysis of XMM-Newton observations. We estimate the corresponding mass-loss rates to be 66.5 ± 11.1, 15.6 ± 4.4 and 9.6 ± 4.1 times the solar mass-loss rate for 70 Ophiuchi, ϵ Eridani and 61 Cygni, respectively, and compare our results with the alternative 'hydrogen wall' method. We also place upper limits on the mass-loss rates of several other main-sequence stars. This method has potential utility for determining the mass-loss rates from X-ray observations showing spatial extension beyond a coronal point source.
UR - http://www.scopus.com/inward/record.url?scp=85190122458&partnerID=8YFLogxK
U2 - 10.1038/s41550-024-02222-x
DO - 10.1038/s41550-024-02222-x
M3 - Article
SN - 2397-3366
VL - 8
SP - 596
EP - 605
JO - Nature Astronomy
JF - Nature Astronomy
IS - 5
ER -