TY  - JOUR
A1  - Reindl, Nicole
A1  - Geier, Stephan
A1  - Ostensen, R. H.
T1  - Discovery of two bright DO-type white dwarfs
JF  - Monthly notices of the Royal Astronomical Society
N2  - We discovered two bright DO-type white dwarfs, GALEXJ053628.3+544854 (J0536+5448) and GALEXJ231128.0+292935(J2311+2929), which rank among the eight brightest DO-type white dwarfs known. Our non-LTE model atmosphere analysis reveals effective temperatures and surface gravities of T-eff = 80000 +/- 4600K and log g = 8.25 +/- 0.15 for J0536+5448 and T-eff = 69400 +/- 900K and log g = 7.80 +/- 0.06 for J2311+2929. The latter shows a significant amount of carbon in its atmosphere (C = 0.003(-0.002)(+0.005), by mass), while for J0536+5448 we could derive only an upper limit of C < 0.003. Furthermore, we calculated spectroscopic distances for the two stars and found a good agreement with the distances derived from the Gaia parallaxes.
KW  - stars: abundances
KW  - stars: atmospheres
KW  - white dwarfs
Y1  - 2018
U6  - https://doi.org/10.1093/mnras/sty1875
SN  - 0035-8711
SN  - 1365-2966
VL  - 480
IS  - 1
SP  - 1211
EP  - 1217
PB  - Oxford Univ. Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Reindl, Nicole
A1  - Finch, Nicolle L.
A1  - Schaffenroth, Veronika
A1  - Barstow, Martin A.
A1  - Casewell, Sarah L.
A1  - Geier, Stephan
A1  - Bertolami Miller, Marcelo Miguel
A1  - Taubenberger, Stefan
T1  - Revealing the true nature of Hen 2-428
JF  - Galaxies
N2  - The nucleus of Hen 2-428 is a short orbital period (4.2 h) spectroscopic binary, whose status as potential supernovae type Ia progenitor has raised some controversy in the literature. We present preliminary results of a thorough analysis of this interesting system, which combines quantitative non-local thermodynamic (non-LTE) equilibrium spectral modelling, radial velocity analysis, multi-band light curve fitting, and state-of-the art stellar evolutionary calculations. Importantly, we find that the dynamical system mass that is derived by using all available He II lines does not exceed the Chandrasekhar mass limit. Furthermore, the individual masses of the two central stars are too small to lead to an SN Ia in case of a dynamical explosion during the merger process.
KW  - binaries: spectroscopic
KW  - stars: atmospheres
KW  - stars: abundances
KW  - supernovae
Y1  - 2018
U6  - https://doi.org/10.3390/galaxies6030088
SN  - 2075-4434
VL  - 6
IS  - 3
ER  - 
TY  - GEN
A1  - Reindl, Nicole
A1  - Finch, Nicolle L.
A1  - Schaffenroth, Veronika
A1  - Barstow, Martin A.
A1  - Casewell, Sarah L.
A1  - Geier, Stephan
A1  - Bertolami Miller, Marcelo Miguel
A1  - Taubenberger, Stefan
T1  - Revealing the true nature of Hen2-428
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - The nucleus of Hen 2-428 is a short orbital period (4.2 h) spectroscopic binary, whose status as potential supernovae type Ia progenitor has raised some controversy in the literature. We present preliminary results of a thorough analysis of this interesting system, which combines quantitative non-local thermodynamic (non-LTE) equilibrium spectral modelling, radial velocity analysis, multi-band light curve fitting, and state-of-the art stellar evolutionary calculations. Importantly, we find that the dynamical system mass that is derived by using all available He II lines does not exceed the Chandrasekhar mass limit. Furthermore, the individual masses of the two central stars are too small to lead to an SN Ia in case of a dynamical explosion during the merger process.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1129 
KW  - binaries: spectroscopic
KW  - stars: atmospheres
KW  - stars: abundances
KW  - Supernovae
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-459703
SN  - 1866-8372
IS  - 1129
ER  -