566 citations · 587 across the 6 of their papers we have counts for
13 papers
Nucleosynthetic signatures of the first stars
Anna Frebel, Wako Aoki, Norbert Christlieb +16
The chemically most primitive stars provide constraints on the nature of the first stellar objects that formed in the Universe; elements other than hydrogen, helium and traces of l…
Identification of a DO white dwarf and a PG1159 star in the ESO SN Ia progenitor survey (SPY)
K. Werner, T. Rauch, R. Napiwotzki +3
We present high-resolution VLT spectra of a new helium-rich DO white dwarf and a new PG1159 star, which we identified in the ESO SPY survey. We performed NLTE model atmosphere anal…
Double degenerates and progenitors of supernovae type Ia
R. Napiwotzki, L. Yungelson, G. Nelemans +12
We report on systematic radial velocity surveys for white dwarf - white dwarf binaries (double degenerates - DDs) including SPY (ESO Supernovae Ia progenitor survey) recently carri…
HE0241-0155 - Evidence for a large scale homogeneous field in a highly magnetic white dwarf
Dieter Reimers, Stefan Jordan, Norbert Christlieb
In the course of the Hamburg/ESO survey we have discovered a white dwarf whose spectrum exhibits many similarities with the prototype of magnetic white dwarfs Grw+708247.…
Search for double degenerate progenitors of supernovae type Ia with SPY
R. Napiwotzki, H. Drechsel, U. Heber +13
We report on a large survey for double degenerate (DD) binaries as potential progenitors of type Ia supernovae with the UVES spectrograph at the ESO VLT (ESO SN Ia Progenitor surve…
Double degenerates from the supernova Ia progenitor survey (SPY)
C. Karl, R. Napiwotzki, U. Heber +4
We report on follow-up observations of double degenerate (DD) white dwarfs from the Supernovae Ia Progenitor Survey (SPY). Orbital parameters of four systems, including a massive s…