ASTRONOMICAL SOCIETY OF THE PACIFICCONFERENCE SERIES

Volume 334

14T H EUROPEAN WORKSHOP ON WHITE DWARFS

Proceedings of a workshop held inKiel, Germany19-23 July 2004

Edited by

D. KoesterInstitutfur Theoretische Physik und Astrophysik

Universitdt Kiel, 24098 Kiel, Germany

and

S. MoehlerInstitutfur Theoretische Physik und Astrophysik

Universitdt Kiel, 24098 Kiel, Germany

Contents

Preface xvi

Participants xvii

Conference Photograph .< xxvii

Part 1. White Dwarf Structure, Evolution, and Galactic Distribution

The White Dwarf Luminosity Function: The Shape of Things toCome 4. 3T. von Hippel, M. Kilic, J. A. Munn, H. HC. arris, K. A. Williams,J. Liebert, D. E. Winget, T. S. Metcalfe, H. L. Shipman, M. A. Wood,T. D. Oswalt, S. J. Kleinman, and A. Nitta

Initial Results From the Lick-Arizona White Dwarf Survey . . 8

K. A. Williams and M. BolteSpectroscopy of Faint White Dwarfs - The DA/DB Ratio

and the Initial-Final Mass Relation 9J. S. Kalirai, H. B. Richer, D. Reitzel, B. M. S. Hansen, R. M. Rich,G. G. Fahlman, B. K. Gibson, and T. von Hippel

On Supermassive White Dwarfs \.. . . . 15

V. WeidemannFaint Blue Objects in the Hubble Deep Field North . 21

M. Kilic, T. von Hippel, R. A. Mendez, and D. E. Winget

A Detailed Photometric Analysis of Halo White DwarfCandidates 27P. Bergeron, M.-T. Ruiz, M. Hamuy, S. K. Leggett, M. J. Currie,C.-P. Lajoie, and P. Dufour

Prospects for Observing White Dwarfs with SIM: the SpaceInterferometry Mission 33H. L. Shipman and J. L. Provencal

Estimating White Dwarf Luminosity Functions 37E. Garcia-Berro, E.M. Geijo, S. Torres, and J. Isern

White Dwarfs and Metal Abundances 43J. Isern, E. Garcia-Berro, I. Domiguez, M. SaJaris, and O. Straniero

v

vi Contents

Carbon in Hot DB White Dwarfs: A New Challenge for theTheory of the Spectral Evolution of White Dwarfs 49

G. Fontaine and P. Brassard

White Dwarfs in LJ Centauri: Preliminary Evidence 55G. Bono, M. Monelli, P. B. Stetson, P. G. Prada Moroni, R. Buonanno, 'A. Calamida, I. Ferraro, G. Iannicola, C. E. Corsi, and L. Pulone

Formation and Evolution of Hydrogen-Deficient post-AGBWhite Dwarfs 61L. Althaus, J. Panei, A. Corsico, E. Garcia-Berro, and C. Scoccola

Determination of a Modern Equation of State for theLiquid/Solid Core of White Dwarf Stars 65A. Kitsikis, G. Fontaine, and P. Brassard

White Dwarf Cooling by Means of Heat Waves 69N. Falcon

Successors of White Dwarfs - Blue Hook Stars and the Late HotFlasher Scenario 73S. Moehler, A. V. Sweigart, W. B. Landsman, N. J. Hammer, andS. Dreizler

White Dwarfs in Open Clusters: Calibrating the Clock 77T. von Hippel, D. E. Winget, W. H. Jefferys, and J. G. Scott

3D-Kinematics of White Dwarfs from the SPY-Project 81E.-M. Pauli, U. Heber, R. Napiwotzki, M. Altmann, and M. Odenkirchen

Spatially Varying IMFs and Halo White Dwarfs 85S. Torres, E. Garcia-Berro, and J. Isern

Mass Determination of DA White Dwarfs from the SloanDigital Sky Survey 89O. Giovannini, A. F. M. da Costa, B. G. Castanheira, and S. O. Kepler

A Model of the Local WD Population 93K.-P. Schroder, R. Napiwotzki, and E.-M. Pauli \

Part 2. Large Surveys

Doubling the Number of White Dwarf Stars: The First SDSSWhite Dwarf Catalog 99

S. J. Kleinman

New High-Proper Motion White Dwarfs in the NLTTCatalog and Sloan Digital Sky Survey 101A. Kawka and S. Venues

Masses, Radii, and Bolometric Luminosities of DA WhiteDwarfs in the First Data Release of the Sloan DigitalSky Survey 107M. Nalezyty, J. Madej, and L. G. Althaus

Contents vii

Cool White Dwarfs from the SuperCOSMOS and Sloan DigitalSky Surveys 113N. C. Hambly, A. P. Digby, and B. R. Oppenheimer

The Use and the Efficiency of the DDO51 Filter for

Identification of Cool White Dwarfs 119

M. Kilic, D. E. Winget, T. von Hippel, and C. F. Claver

How Many Hot Subdwarf Stars Were Rejected from the PGSurvey? 123R. A. Wade, M. A. Stark, and R. F. Green

Sloan Digital Sky Survey: Proper Motion Systems ContainingWhite Dwarfs 127J. A. Smith, N. M. Silvestri, T. D. Oswalt, H. C. Harris, S. J. Kleinman,J. A. Munn, A. Nitta, and M. A. Rudkin

Discovery of 282 Cool White Dwarfs (Tef[ <̂ 8000 K) in theSloan Digital Sky Survey 131M. Kilic, J. A. Munn, H. C. Harris, J. Liebert, T. von Hippel,K. A. Williams, T. S. Metcalfe, and D. E. Winget

The GSC2 Survey of Cool White Dwarfs 135D. Carollo, A. Spagna, M. G. Lattanzi, R.L. Smart, B. Bucciarelli,L. Terranegra, S. T. Hodgkin, and B. McLean

4

Analysis of DA White Dwarfs from the McCook & Sion Catalog 139A. Gianninas, P: Bergeron, and P. Dufour

Searching for White and Brown Dwarfs in the Frame of theMUSYC/CYDER Survey 143M. Altmann, R. A. Mendez, M.-T. Ruiz, W. van Altena, E. Gawiser,J. Maza, and P. van Dokkum

White Dwarfs in the ALHAMBRA Survey 147S. CataMn, J. Isern, E. Garcia-Berro, S. Torres, and the ALHAMBRATeam >

Part 3. Atmospheres, Abundances, Magnetic Fields

Fossil Fields in Magnetic White Dwarfs 153D. T. Wickramasinghe and L. Ferrario

K i l o - G a u s s M a g n e t i c F i e l d s i n T h r e e D A W h i t e D w a r f s . . . . 1 5 9R. Aznar Cuadrado, S. Jordan, R. Napiwotzki, H. M. Schmid,S. K. Solanki, and G. Mathys

On Possible Oxygen/Neon White Dwarfs: H1504+65 and theWhite Dwarf Donors in Ultracompact X-ray Binaries . . 165

K. Werner, JV. J. Hammer, T. Nagel, T. Rauch, and S. Dreizler

Twenty Years of Studies on H1504+65 171

M. S. Sliwinski and L.I. Sliwinska

viii Contents

HST Observations of the Sirius B Baimer Lines 175M. A. Barstow, M. R. Burleigh, J. B. Holberg, I. Hubeny, H. E. Bond,and D. Koester

Is the Distribution of Nitrogen in the Atmospheres of Hot DAWhite Dwarfs Inhomogeneous? 181

P. Chayer, S. Venues, and J. Dupuis

Lyman Line Spectroscopy of Hot Hydrogen-Rich White DwarfsRevisited 185

S. Vennes, P. Chayer, J. Dupuis, and T. Lanz

Results from a FUSE Survey of Hot White Dwarfs 191J. Dupuis, P. Chayer, S. Vennes, J. W. Kruk, L. M. Torres, andP. J. Sanchez

Detailed Spectroscopic and Photometric Analysis of DQ WhiteDwarfs 197

P. Dufour, P. Bergeron, and G. Fontaine

Non-Ideal Equation of State, Refraction and Opacities in VeryCool, Helium-Rich White Dwarf Atmospheres 203

P. M. Kowalski, D. Saumon, and S. Mazevet

Modelling Alkali Line Absorption and Molecular Bands in CoolDAZs - 209D. Homeier, N. Allard, F. Allard, P. H. Hauschildt, A. Schweitzer,P. C. Stencil, and P. F. Week

DAZ White Dwarfs in the SPY Sample 215D. Koester, K. Rollenhagen, R. Napiwotzki, B. Voss, N. Christlieb,D. Homeier, and D. Reimers

Identification of a DO White Dwarf and a PG1159 Star in theESO SN la Progenitor Survey (SPY) 221K. Werner, T. Rauch, R. Napiwotzki, N. Christlieb, D. Reimers, andC.A. Karl

FUSE spectroscopy of PG 1159 Stars )• 225

E. Reiff, T. Rauch, K. Werner, and J. W. Kruk

Deposing the Cool Corona of KPD 0005+5106 229

K. Werner and J. J. Drake

Spectral Analyses of DO White Dwarfs and PG1159 Stars fromthe Sloan Digital Sky Survey 233S. D. Hiigelmeyer, S. Dreizler, K. Werner, A. Nitta, S. J. Kleinman, andJ. Krzesinski

Metal Abundances in Hot DA White Dwarfs 237

S. Schuh, M. A. Barstow, and S. Dreizler

Rotation Velocities of DA White Dwarfs with ConvectiveAtmospheres 241C. Karl, U. Heber, R. Napiwotzki, S. Dreizler, D. Koester, and I. N. Reid

Contents ix

The Discovery of Oxygen Rich Chromospheres in Two MassiveDQ White Dwarfs 245

J. L. Provencal, H. L. Shipman, and J. MacDonald

Comparison of White Dwarf Mass Determinations 249

S. Boudreault and P. Bergeron

Model Atmospheres for Hot Evolved Stars: Revising the

Treatment of Continuous Opacities 253

JV. Behara and C. S. Jeffery

Discovery of Magnetic Fields in CPNs 257

S. Jordan, K. Werner, and S. J. O'Toole

Discovery of Magnetic Fields in Hot Subdwarfs 261

S. J. O'Toole, S. Jordan, S. Friedrich, and UHeber

Constraining Gravitational Theories by Observing MagneticWhite Dwarfs 265

O. Preuss, S. Jordan, M. P. Haugan, and S. K. Solanki

Surface Magnetic Field Distributions of the White Dwarfs PG1015+014 and HE 1045-0908 269

F. Euchner, S. Jordan, K. Reinsch, K. Beuermann, and B. T. Gansicke

Do Magnetic Fields Prevent Hydrogen from Accreting onto CoolMetal-line White Dwarf Stars? 273

S. Friedrich, S. Jordan, and D. Koester

Heterogeneous Magnetospheres of Accretion-Induced Collapsing

White Dwarfs 277

V. Kryvdyk and A. Agapitov

Magnetic Fields and Rotation of Compact Stars 281

L. Ferrario and D. T. Wickramasinghe

I r r a d i a t i o n E f f e c t s i n C l o s e D e g e n e r a t e B i n a r y S y s t e m s , . . . . 2 8 5

T. Palma and R. D. Rohrmann

Part 4. White Dwarf Progenitors: CSPNe, SDBs, SDOs

Spectroscopic Analyses of Helium-rich Subdwarf B Stars . .'••. . 291

A. Ahmad and C. S. Jeffery

The Upward Diffusion of Hydrogen in Helium-Rich SubdwarfB Stars 297

K. Unglaub

Subdwarf B Stars from the ESO Supernova la ProgenitorSurvey - Observation versus Theory 303T. Lisker, U. Heber, R. Napiwotzki, N. Christlieb, Z. Han, D. Homeier,and D. Reimers

x Contents

Subluminous O Stars from the ESO Supernova ProgenitorSurvey - Observation versus Theory 309

A. Stroer, U. Heber, T. Lisker, R. Napiwotzki, and S. Dreizler

Metal Abundances in sdBs from UV Spectroscopy 315S. J. O'Toole

Iron Abundance in Hydrogen-Rich CentralStars of Planetary Nebulae 321A. I. D. Hoffmann, I. Traulsen, T. Rauch, K. Werner, S. Dreizler, andJ. W. Kruk

HST and FUSE Spectroscopy of Hot Hydrogen-Rich CentralStars of Planetary Nebulae 325I. Traulsen, A. I. D. Hoffmann, T. Rauch, K. Werner, S. Dreizler, andJ. W. Kruk

Spectral Analysis of Central Stars of PNe Interacting with theInterstellar Medium 329

T. Rauch and F. KerberSubdwarf B Binaries from the Edinburgh-Cape Survey 333

L. Morales-Rueda, P. F. L. Maxted, T. R. Marsh, D. Kilkenny, andD. O'Donoghue

Mass-Loss and Multicomponent Flow from Central Stars ofPlanetary Nebulae . < 337

J. Krticka and J. KubatHydrogen-Deficient Stars in Pre-WD Stages 341

W.-R. Hamann and G. GrafenerLMC-N66: A Potential SN la Progenitor? 345

W.-R. Hamann, M. Pena, and G. Grafener

Part 5. White Dwarf and Progenitors in Binaries

Subdwarf B Binaries as an Important Progenitor Channel forCataclysmic Variables 351

K. SchenkerThe Mass of the sdB Primary of the Binary HS 2333+3927 . 357

U. Heber, H. Drechsel, C. Karl, R. Qstensen, S. Folkes, R. Napiwotzki,M. Altmann, O. Cordes, J.-E. Solheim, B. Voss and D. Koester

The Secondary Companions in Short-Period sdB Binaries . . . 363

E. M. Green, B.-Q. For, and E. A. Hyde

Subdwarf B Binaries from the SPY Project 369C. Karl, U. Heber, and R. Napiwotzki

New Results from the Supernova la Progenitor Survey 375R. Napiwotzki, C. A. Karl, G. Nelemans, L. Yungelson, N. Christlieb,H. Drechsel, U. Heber, D. Homeier, D. Koester, J. Kruk, B. Leibundgut,T. R. Marsh, S. Moehler, A. Renzini, and D. Reimers X

Contents xi

Observations of Ultra-short Period Double-degenerate WDBinary Candidates 381

K. Reinsch

The White Dwarfs in AM CVn Systems - Candidates for SNla? 387J.-E. Solheim and L. R. Yungelson

Ultraviolet Observations of the Young Pre-IP CandidateHS1136+6646 393D. K. Sing, J. B. Holberg, S. Howell, M. Burleigh, S. Good, andM. Barstow

Two Ultracool Degenerate Companions 398

J. Farihi

NLTE Analysis of the Ultra-short Period White-Dwarf BinaryRX J0806.3+1527 T 399J. Steiper, K. Reinsch, and S. Dreizler

The Solution of the Radiative Transfer Equation in AccretionDiscs of Cataclysmic Variables 403

D. Korcakova, J. Kubat, and A. Kawka

A Search for Unresolved Double Degenerates Using IUE Archives 407C.-P. Lajoie and P. Bergeron"

C a n W h i t e D w a r f s i n I n t e r m e d i a t e P o l a r s b e U n v e i l e d ? . . . . 4 1 1D. de Martino, M. Mouchet, J.-M. Bonnet-Bidaud, B. T. Gansicke, andF. Haberl

Spectropolarimetry of Magnetic Cataclysmic Variables and WhiteDwarfs with the SALT 415D. A. H. Buckley, D. O'Donoghue, S. B. Potter, and K. H. Nordsieck

Finding the Cool Companions of the PG DA White Dwarfs . 419J. B. Holberg and K. Magargal

Spectral Analysis of Super Soft X-ray Sources: V4743 Sagittarii 423T. Rauch, M. Orio, R. Gonzales-Riestra, and M. Still

Mixed Hydrogen-Helium White Dwarfs in Short Period X-rayBinaries : 427A. M. Teodorescu, F. D'Antona, and P. Ventura

A NICMOS Direct Imaging Search for Giant Planets around theSingle White Dwarfs in the Hyades 431S. Friedrich, H. Zinnecker, W. Brandner, S. Correia, andM. McCaughrean

Resolving sdB Binary Systems with Adaptive Optics 435

R. 0stensen, U. Heber, and P. Maxted

Disentangling Composite Spectrum Hot Subdwarfs 439

M. A. Stark and R. A. Wade

xii Contents

SDSS J1240-01: A New AM CVn Star with a 37-MinuteOrbital Period 443G. H. A. Roelofs, P. J. Groot, T. R. Marsh, D. Steeghs, and G. Nelemans

Spin- Up and Spin-Down of Magnetic White Dwarfs inCataclysmic Variables: Theory vs Long-Term Monitoring 447

I. L. Andronov

Part 6. Variable White Dwarfs and Progenitors

Non-Radial Oscillations in CV Primaries 453

B. Warner and P. A. Woudt

Questioning the Purity of the ZZ Ceti Instability Strip 459A. S. Mukadam, D. E. Winget, T. von Hippel, M. H. Montgomery,S. O. Kepler, and A. F. M. Costa

The Crystal Method: Asteroseismology of BPM 37093 465

T. S. Metcalfe, M. H. Montgomery, and A. Kanaan

Time-Series Spectroscopy of DAVs 471S. E. Thompson, J. C. Clemens, and D. Koester

Whole Earth Telescope Observations of the ZZ Ceti StarHLTau76 477G. Vaudair et aJ. (the WET collaboration)

White Dwarf Lightcurves: Constraining Convection and ModeIdentification Using Non-sinusoidal Lightcurves 483M. H. Montgomery

Exploring Uncharted Territory in Particle Physics UsingPulsating White Dwarfs: Prospects 489A. Kim, D. E. Winget, M. H. Montgomery, and D. J. Sullivan •

EC 20058-5234: A DBV White Dwarf and a Possible PlasmonNeutrino Detector 495

D. J. Sullivan

Measuring Evolutionary Rates 501S. O. Kepler, J. E. S. Costa, A. Mukadam, F. Mullally, D. E. Winget,R. E. Nather, and D. Sullivan

Distances to Selected Variable White Dwarf Stars 506

F. Mullally and M. de Graff

I n v e s t i g a t i o n o f t h e S p e c t r a l V a r i a b i l i t y o f P G 1 1 5 9 - 0 3 5 . . . . 5 1 2

S. Dreizler, K. Werner, and T. Stann

The Domains of Instability for the Pulsating PG 1159 Stars . 518P.-O. Quirion, G. Fontaine, P. Brassard, and F. Herwig

Contents xiii

High Sensitivity Observations and Detailed AsteroseismologicalAnalysis of the EC14026 Star Feige 48 524

S. Charpinet, G. Fontaine, P. Brassard, M. Billeres, E. M. Green, andP. Chayer

Discovery of a Long-Period Photometric Variation in theV361Hya Star HS 0702+6043 530S. Schuh, J. Huber, E. M. Green, S. J. O'Toole, S. Dreizler, U. Heber,and G. Fontaine

Mode Identification in Pulsating sdB Stars from ULTRACAM

Observations 536

C. S Jeffery, V. S. Dhillon, T. R. Marsh, and B. Ramachandran

The Effects of Crystallization on the Pulsational Properties of

Massive ZZ Ceti Stars 537

A. H. Corsico, L. G. Althaus, M. H. Montgomery, and E. Garcia-Berro

High Speed Photometry of White Dwarfs with Small Telescopes 541

J. L. Provencal, H. L. Shipman, D. Childers, and A. Nitta

T h e S p e c t r a l V a r i a b i l i t y of P u l s a t i n g S t a r s : P G 1 1 5 9 - 0 3 5 . . . 5 4 5

T. Stain, S. Dreizler, and K. Werner

HST Observations of the Pulsating White Dwarf GD 358 . . . 549

B. G. Castanheira, S. O. Kepler, A. Nitta, D. E. Winget, and D. Koester

The Vibrating String Analogy and Mode Trapping 553

M. H. Montgomery

Revisiting the DBs Instability Strip Using UV Spectra 557

B. G. Castanheira, S. O. Kepler, D. Koester, and G. Handler

Analysis of HST and IUE Data of the DBV Star PG1351+489 561

V. M. Alves, J. E. S. Costa, S. O. Kepler, and D. Koester

Asteroseismology of the Crystallized ZZ Ceti Star BPM 37093:A Different View (Part II) 565

G. Fontaine and P. Brassard \T h e P u l s a t i n g D A W h i t e D w a r f S t a r E C 1 4 0 1 2 - 1 4 4 6 . : . . . . 5 6 9

G. Handler and E. Romero-ColmeneroConstraints on the Structure of HL Tau 76 Derived from

Asteroseismology 573

D. Pech, G. Vaudair, and N: Dolez

Asteroseismic Results for GD 154 • • 577

D. 6. Hiirkal, G. Handler, B. A. Steininger, and M. D. Reed

Eleven New DAVs from the Sloan Survey 581F. Mullally, S. E. Thompson, B. G. Castanheira, D. E. Winget,S. O. Kepler, D. J. Eisenstein, S. J. Kleinman, and A. Nitta

New DBVs from the SDSS 585A. Nitta, S. J. Kleinman, J. Krzesinski, A. S. Mukadam, F. Mullally,R. E. Nather, D. J. Sullivan, S. E. Thompson, D. E. Winget, andM. A. Wood

xiv Contents

Search for IR Excess in White Dwarf Stars 589A. Nitta, J. L. Provencal, M. Kilic, S. J. Kleinman, J. Liebert, andT. von Hippel

A Convective Model for Light Curves of ZZ Ceti Stars 593

N. Falcon •

White Dwarf Observations in Hungary 597

M. Papard, R. Szabo, and Z. Csubry

Analysis of a Sample of Candidate DAV Stars 601

B. Voss and D. KoesterProgress Report on the Search for Variability Among Cool White

Dwarfs 605

T. D. Oswalt, M. Rudkin, K. Johnston, J. Kissinger, and K. Menezes

Pulsating Subdwarf B Stars in Close Binaries 607

M. D. Reed and B. J. Brondel

New Observations of the Hot PNNV Sanduleak 3 611B. Steininger, M. Pretorius, M. Breger, and R. R. Shobbrook

Fundamental Parameters of the sdB Pulsator PG 1219+534'-The Importance of High Sensitivity Observations forDetailed Asteroseismology of EC 14026 Stars 615

S. Charpinet, G. Fontaine, P. Brassard, E. M. Green, and P. Chayer

The Asteroseismic Analysis of the EC14O26 Star PG 0014+067Revisited 619S. Charpinet, G. Fontaine, P. Brassard, M. Billeres, E. M. Green, andP. Chayer

PB8783 Revisited 623

M. VucJcovic, S. Hostler, S. D. Kawaler, and B. Behera

Searching for Pulsations among sdOs 627C. Rodriguez-Lopez, A. Ulla, R. Garrido, M. Manteiga, V. Casanova,A. Sota, R. 0stensen, and R. Oreiro

Balloon09010001: Towards the White Dwarf Stage? 631R. Oreiro, A. Ulla, F. Perez, Hernandez, J. MacDonald, R. 0stensen, andC. Rodriguez Lopez

An Asteroseismological Analysis of the Short-Period PulsatingsdB star EC 05217-3914 635

M. Billeres and G. Fontaine

A New Computer Code for Analyzing the Light Curves ofEclipsing Pre-Cataclysmic Binaries (PCBs): Applicationto UU Sge and V477 Lyr 639

V.-V. Pustynski and I. Pustylnik

Photometric Variability in the Faint Sky Variability Survey . . 643L. Moraies-Rueda, P. J. Groot, T. Augusteijn, G. Nelemans,P. M. Vreeswijk, and E. J. M. van den Besselaar

Contents xv

Detection of Pulsations in the Newly Discovered PGil59 StarHE 1429-1209 647T. JVagei and K. Werner

Two New ZZ Ceti Pulsators from the HS and HE Surveys . . 651R. Silvotti, B. Voss, D. Koester, and I. Bruni

Analysis of High Resolution White Dwarf Spectra from the ESOSNIa Progenitor Survey (SPY) 655B. Voss, D. Koester, and the SPY consortium

ACF Analysis of Irregularly Spaced Observations of theAccretion Structures near White Dwarfs 659

I. L. Andronov and L. L. Chinarova

Author Index .^. 663