English

Which Hydrogen Balmer Lines Are Most Reliable for Determining White Dwarf Atmospheric Parameters?

Solar and Stellar Astrophysics 2014-10-17 v1

Abstract

Our preliminary results from laboratory experiments studying white dwarf (WD) photospheres show a systematic difference between experimental plasma conditions inferred from measured Hβ\beta absorption line profiles versus those from Hγ\gamma. One hypothesis for this discrepancy is an inaccuracy in the relative theoretical line profiles of these two transitions. This is intriguing because atmospheric parameters inferred from H Balmer lines in observed WD spectra show systematic trends such that inferred surface gravities decrease with increasing principal quantum number, nn. If conditions inferred from lower-nn Balmer lines are indeed more accurate, this suggests that spectroscopically determined DA WD masses may be greater than previously thought and in better agreement with the mean mass determined from gravitational redshifts.

Keywords

Cite

@article{arxiv.1410.4215,
  title  = {Which Hydrogen Balmer Lines Are Most Reliable for Determining White Dwarf Atmospheric Parameters?},
  author = {Ross E. Falcon and G. A. Rochau and J. E. Bailey and T. A. Gomez and M. H. Montgomery and D. E. Winget and T. Nagayama},
  journal= {arXiv preprint arXiv:1410.4215},
  year   = {2014}
}

Comments

To appear in the proceedings of the 19th European White Dwarf Workshop held August 11-15, 2014 in Montreal, Canada