English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Formation of circumstellar lines of Na I and Ca II in type Ia supernovae isstudied for the case, when supernova explodes in a binary system with a redgiant. The model suggests a spherically-symmetric wind and takes into accountionization and heating of the wind by X-rays from the shock wave and bygamma-quanta of ^{56}Ni radioactive decay. For the wind density typical of thered giant the expected optical depth of the wind in Na I lines turnes out toolow (\tau<0.001}) to detect the absorption. For the same wind densities thepredicted optical depth of Ca II 3934 \AA is sufficient for the detection(\tau>0.1). I conclude that the absorption lines detected in SN 2006X cannotform in the red giant wind; they are rather related to clouds at distanceslarger than the dust evaporation radius (r>10^{17} cm). From the absence in SN2006X of Ca II absorption lines not related with the similar Na I components Iderive the upper limit of the mass loss rate by the wind with velocity u:\dot{M}<10^{-8}(u/10 km/s) M_{\odot} yr^{-1}.

Circumstellar Na I and Ca II lines of type Ia supernovae in symbiotic scenario