New answers tagged

3

You may want to look at "Stellar Structure and Evolution" by Kippenhahn, Weigert and Weiss. Paragraph 36.3.1 "Simple collapse solutions" contains just what you are looking for. In particular, figure 36.5 shows the velocity profile as a function of the radial mass coordinate. I have reproduced the figure here: The reasoning is more or ...


18

Two things. The abundance of oxygen is a difficult thing to measure in optical spectra - much harder than Mg, Ca, and Si. So these latter are usually used to represent "the alpha elements". There is a strong OI triplet at 777 nm and a much weaker OI forbidden line at 630 nm. But these often give contrary results because they are blended with other ...


3

In a nova, a layer of hydrogen is pulled from a regular star, forming a kind of dense atmosphere around the white dwarf. This atmosphere is heated by the white dwarf, until a critical temperature is reached, and fusion begins in the atmosphere. The white dwarf is rather unaffected by this, and the process of forming a hydrogen atmosphere can restart. ...


Top 50 recent answers are included