TY  - JOUR
A1  - Martinez-Nunez, Silvia
A1  - Sander, Angelika
A1  - Gimenez-Garcia, Angel
A1  - Gonzalez-Galan, Ana
A1  - Torrejon, Jose Miguel
A1  - Gonzalez-Fernandez, Carlos
A1  - Hamann, Wolf-Rainer
T1  - The donor star of the X-ray pulsar X1908+075
T2  - Astronomy and astrophysics : an international weekly journal
N2  - High-mass X-ray binaries consist of a massive donor star and a compact object. While several of those systems have been well studied in X-rays, little is known for most of the donor stars as they are often heavily obscured in the optical and ultraviolet regime. There is an opportunity to observe them at infrared wavelengths, however. The goal of this study is to obtain the stellar and wind parameters of the donor star in the X1908+075 high-mass X-ray binary system with a stellar atmosphere model to check whether previous studies from X-ray observations and spectral morphology lead to a sufficient description of the donor star. We obtained H-and K-band spectra of X1908+075 and analysed them with the Potsdam Wolf-Rayet (PoWR) model atmosphere code. For the first time, we calculated a stellar atmosphere model for the donor star, whose main parameters are: M-spec = 15 +/- 6 M-circle dot, T-* = 23(-3)(+6) kK, log g(eff) = 3.0 +/- 0.2 and log L/L-circle dot = 4.81 +/- 0.25. The obtained parameters point towards an early B-type (B0-B3) star, probably in a supergiant phase. Moreover we determined a more accurate distance to the system of 4.85 +/- 0.50 kpc than the previously reported value.
KW  - binaries: close
KW  - stars: individual: X1908+075
KW  - stars: massive
KW  - stars: winds
KW  - outflows
KW  - X-rays: binaries
Y1  - 2015
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/38851
SN  - 0004-6361
SN  - 1432-0746
VL  - 578
PB  - EDP Sciences
CY  - Les Ulis
ER  -