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  • HUBBLE SPACE TELESCOPE FAR ...
    Godon, Patrick; Sion, Edward M; Starrfield, Sumner; Livio, Mario; Williams, Robert E; Woodward, Charles E; Kuin, Paul; Page, Kim L

    Astrophysical journal. Letters, 04/2014, Letnik: 784, Številka: No 2
    Journal Article

    With six recorded nova outbursts, the prototypical recurrent nova T Pyxidis (T Pyx) is the ideal cataclysmic variable system to assess the net change of the white dwarf mass within a nova cycle. Recent estimates of the mass ejected in the 2011 outburst ranged from a few ~10 to 3.3 × 10 , and assuming a mass accretion rate of 10 -10 yr for 44 yr, it has been concluded that the white dwarf in T Pyx is actually losing mass. Using NLTE disk modeling spectra to fit our recently obtained COS and STIS spectra, we find a mass accretion rate of up to two orders of magnitude larger than previously estimated. Our larger mass accretion rate is due mainly to the newly derived distance of T Pyx (4.8 kpc, larger than the previous 3.5 kpc estimate), our derived reddening of ( - ) = 0.35 (based on combined and spectra), and NLTE disk modeling (compared to blackbody and raw flux estimates in earlier works). We find that for most values of the reddening (0.25 ≤ ( - ) ≤ 0.50) and white dwarf mass (0.70 ≤ ≤ 1.35 ) the accreted mass is larger than the ejected mass. Only for a low reddening (~0.25 and smaller) a large white dwarf mass (0.9 and larger) is the ejected mass larger than the accreted one. However, the best results are obtained for a larger value of reddening.