Prediction for the He i λ10830 Å absorption wing in the coming event of η Carinae

Amit Kashi*, Noam Soker

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


We propose an explanation for the puzzling appearance of a wide blue absorption wing in the He i λ10830 Å P Cygni profile of the massive binary star η Car several months before periastron passage. Our basic assumption is that the colliding winds region is responsible for the blue wing absorption. By fitting observations, we find that the maximum outflow velocity of this absorbing material is ∼2300 km s-1. We also assume that the secondary star is towards the observer at periastron passage. With a toy model, we achieve two significant results. (1) We show that the semimajor axis orientation we use can account for the appearance and evolution of the wide blue wing under our basic assumption. (2) We predict that the Doppler shift (the edge of the absorption profile) will reach a maximum 0-3 weeks before periastron passage, and not necessarily exactly at periastron passage or after periastron passage.

Original languageEnglish
Pages (from-to)923-928
Number of pages6
JournalMonthly Notices of the Royal Astronomical Society
Issue number2
StatePublished - Apr 2009
Externally publishedYes


  • Binaries: general
  • Stars: individual: η Car
  • Stars: mass-loss
  • Stars: winds, outflows

Fingerprint Dive into the research topics of 'Prediction for the He i λ10830 Å absorption wing in the coming event of η Carinae'. Together they form a unique fingerprint.

Cite this