English

Spiral Structure in WZ Sagittae around the 2001 Outburst Maximum

Astrophysics 2015-06-24 v1

Abstract

Intermediate resolution phase-resolved spectra of WZ Sge were obtained on five consecutive nights (July 23 -- 27) covering the initial stage of the 2001 superoutburst. Double-peaked emission lines of He\textsc{II} at 4686 \AA, which were absent on July 23, emerged on July 24 together with emission lines of C\textsc{III} / N\textsc{III} Bowen blend. Analyses of the He\textsc{II} emission lines using the Doppler tomography revealed an asymmetric spiral structure on the accretion disk. This finding demonstrates that spiral shocks with a very short orbital period can arise during the initial stage of an outburst and may be present in all SU UMa stars.

Keywords

Cite

@article{arxiv.astro-ph/0112374,
  title  = {Spiral Structure in WZ Sagittae around the 2001 Outburst Maximum},
  author = {Hajime Baba and Kozo Sadakane and Yuji Norimoto and Kazuya Ayani and Masayuki Ioroi and Katsura Matsumoto and Daisaku Nogami and Makoto Makita and Taichi Kato},
  journal= {arXiv preprint arXiv:astro-ph/0112374},
  year   = {2015}
}

Comments

5 pages, 8 figures, accepted for publication in PASJ