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White Dwarf and Hot Subdwarf Binaries As Possible Progenitors of Type I A

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White Dwarf and Hot Subdwarf Binaries As Possible Progenitors of Type I A White dwarf and hot sub dwarf binaries as p ossible progenitors of type I a Sup ernovae Christian Karl July White dwarf and hot sub dwarf binaries as p ossible progenitors of type I a Sup ernovae Den Naturwissenschaftlichen Fakultaten der FriedrichAlexanderUniversitatErlangenN urnberg zur Erlangung des Doktorgrades vorgelegt von Christian Karl aus Bamberg Als Dissertation genehmigt von den Naturwissenschaftlichen Fakultaten der UniversitatErlangenN urnberg Tag der m undlichen Pr ufung Aug Vositzender der Promotionskommission Prof Dr L Dahlenburg Erstb erichterstatter Prof Dr U Heb er Zweitberichterstatter Prof Dr K Werner Contents The SPY pro ject Selection of DB white dwarfs Color criteria Absorption line criteria Summary of the DB selection The UV Visual Echelle Sp ectrograph Instrumental setup UVES data reduction ESO pip elin e vs semiautomated pip eline Derivation of system parameters Denition of samples Radial velocity curves Followup observations Radial velocity measurements Power sp ectra and RV curves Gravitational redshift Quantitative sp ectroscopic analysis Stellar parameters of singleline d systems Stellar parameters of doubleline d systems Pro jected rotational velocities Metal abundances of sdB stars Doublelined white dwarfs Systems analyzed from their radial velocity curves alone WD HE WD Systems that cannot b e solved from their RV curves alone HE a system solved through an additional sp ectral analysis WD a system in need of an additional sp ectral analysis i ii CONTENTS White dwarfs with M dwarf companions WD alias RR Caeli WD HS HE Singlelined systems White dwarf primaries WD WD HS WD Sub dwarf B primary WD HE HE HE HE HE HE Sub dwarf O primary HE HE HE Peculiar ob jects PN G alias EGB a central star of a planetary nebula WD a white dwarf with a p eculiar H prole Stars with small RV amplitudes HE WD WD WD WD WD HS Conclusion and outlo ok Conclusion Outlo ok A Selected DB candidates from the Hamburg ESO Survey CONTENTS iii B Followup campaigns B Campaigns at the DSAZ m telescop e B Campaigns at the ESO NTT B Campaigns at the ESO VLT B Campaigns at the WHT and INT C Radial velocity measurements D Equivalent widths measurements E List of abbreviations List of Figures Sp ectrum of a type Ia Sup ernova Lightcurve of a type Ia Sup ernova Progenitors of type Ia Sup ernova Sample UVES sp ectrum of a hydrogenrich DA white dwarf White dwarf distribution SPY detection probability as a function of orbital p erio d DB selection Color criteria DB selection Signicance threshold DB selection Cuto criteria The UV Visual Echelle Sp ectrograph Sample UVES CCD exp osure UVES reduction pattern Order denition for UVES sp ectra Overlapping unblazed echelle orders The ripple problem Reduced UVES sp ectrum ESO pip eline vs our own semiautomated pip eline RV determination by means of MIDAS ts RV curves of a single and a double lined system Massradius relation for white dwarfs Evolutionary tracks for DA white dwarfs Evolutionary tracks for sdB stars Sample mo del ts of doublelined systems Analysis of a doublelined system WD Observed line prole WD Best t RV curve and p ower sp ectrum HE Best t RV curve and p ower sp ectrum WD Best t RV curve and p ower sp ectrum HE Line shift within one night HE Best t RV curve and p ower sp ectrum HE Sample mo del atmosphere ts WD Observed line proles WD Best t RV curve and p ower sp ectrum iv LIST OF FIGURES v Sample UVES sp ectrum of a white dwarf with an M dwarf companion WD Best t RV curve and p ower sp ectrum WD Emission lines WD Splitted Balmer lines WD Best t RV curve and p ower sp ectrum HS Best t RV curve and p ower sp ectrum HS Observed line proles HE Best t RV curve and p ower sp ectrum Analysis of singlelined systems WD Best t RV curve and p ower sp ectrum WD Best t RV curve and p ower sp ectrum .
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