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Search for progenitors of supnernovae type Ia with SPY

R. Napiwotzki·N. Christlieb·H. Drechsel·H. -J. Hagen·U. Heber·D. Homeier·C. Karl·D. Koester·B. Leibundgut·T. R. Marsh·S. Moehler·G. Nelemans·E. -M. Pauli·D. Reimers·A. Renzini·L. Yungelson
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Abstract

We have started 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 surveY - SPY). About 400 white dwarfs were checked for radial velocity variations during the first 15 months of this project, twice the number of white dwarfs investigated during the last 20 years. We give an overview of the SPY project and present first results Fifty four new DDs have been discovered, seven of them double lined (only 18 and 6 objects of these groups were known before, respectively). The final sample is expected to contain 150 to 200 DDs. Eight new pre-cataclysmic binaries were also detected. SPY is the first DD survey which encompasses also non-DA white dwarfs. SPY produces an immense, unique sample of very high resolution white dwarf spectra, which provides a lot of spin-off opportunities. We describe our projects to exploit the SPY sample for the determination of basic parameters, kinematics, and rotational velocities of white dwarfs. A catalogue with a first subset of our white dwarf data has already been published by Koester et al. 2001.

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R. Napiwotzki, N. Christlieb, H. Drechsel, H. -J. Hagen, U. Heber, D. Homeier, C. Karl, D. Koester, B. Leibundgut, T. R. Marsh, S. Moehler, G. Nelemans, E. -M. Pauli, D. Reimers, A. Renzini, L. Yungelson. 2002-03-09. Search for progenitors of supnernovae type Ia with SPY. https://doi.org/10.1002/1521-3994(200112)322%3A5%2F6%3C411%3A%3Aaid-asna411%3E3.0.co%3B2-i

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