WHITE DWARFS IN NOVALIKE VARIABLES Edward M Sion
WHITE DWARFS IN NOVALIKE VARIABLES Edward M. Sion Department of Astronomy & Astrophysics, Villanova University
Collaborators • Patrick Godon, Villanova University • Al Linnell, University of Washington • Paula Szkody, University of Washington • Ivan Hubeny, University of Arizona • Current and Former Villanova Students Ryan Hamilton, Joel Urban, Trisha Mizusawa, Ronald-Louis Ballouz
Detection of WDs in Nova-Likes • • Systems (except BK Lyn) Above the Gap Luminous Disks Outflowing Wind Low states relatively rare & shorter than high states Many nova-likes are viewed at high inclination (obscures WD and BL) Low Inclination NLs (WD hidden? )
CENSUS of WDs in Nova-Likes V 794 Aql {BK Lyn } {V 442 Oph} {KR Aur} IX Vel {V 3885 Sgr} VY Scl {BB Dor} MV Lyr DW UMa TT Ari
RW Tri (Mizusawa et al. 2009, PASP in preparation) d = 341 + 38/-41 pc M_wd = 0. 4 Msun, Mdot = 6. 3 x 10^-9 Msun/yr 7 Archival IUE Spectra from Feb. 1980 to Aug. 1982
KR Aur Mizusawa et al. 2009, PASP, in prep.
V 442 Oph Ballouz & Sion, 2009, Ap. J, in press
BB Dor Mdot = 1 x 10^-9 Msun/yr T_wd ~ 32000 K (T_wd =37, 000 K) i = 8 degrees (80 degrees) Godon et al. 2008, Ap. J, 687, 532
BK Lyn • • • VY Scl-type Nova-Like Variable Only Nova-Like below the Period Gap P_orb = 108 min i < 80 degrees; i > 20 degrees M_wd = 0. 3 +0. 35 /- 0. 12 Msun (Dobrzycka & Howell 1992) d = 116 to 1. 5 kpc? HST STIS G 140 L Obs (4/13/03) B. Gaensicke, PI No P Cygni features, strong emission, sharp Ly. A Spectroscopic Twin of V 794 Aql (P_orb = 221 min)
BK Lyn Ballouz, Sion, Gaensicke, Long, 2009, in preparation
BK Lyn Disk Fitting Results (Ballouz et al. 2009, in preparation) Mwd Mdot i chi^2 d (pc) 1. 2 -9/-9. 5 75 -81 1. 84 -1. 9 300 -550 1. 0 -9. 0 75 -81 1. 94 400 -700 0. 8 -8. 5 75 -81 1. 97 560 -940 0. 55 -8. 0 75 -81 1. 97 -2. 00 730 -1220 0. 40 -8. 0 75 2. 07 860
V 3885 Sgr • • UX UMa-type Nova-Like P_orb = Luminous Disk, Wind Mdot = 5 x 10^-9 Msun/yr M_wd = 0. 8 Msun i = 40 – 60 degrees d = 500 pc
V 3885 Sgr T_wd = 57, 000 +/- 5000 K Linnell et al. 2009, Ap. J, submitted
Conclusions • # of NL WDs with Teff’s slowly increasing • All (so far) have Teff > 30, 000 K • All are hottest WDs at their P_orb • V 3885 Sgr has T_wd = 57, 000 +/- 5000 K • We must have TOO program with HST to Catch NL Systems in Low States
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