Talk:Type Ia supernova

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Good article Type Ia supernova has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do. If it no longer meets these criteria, you can delist it, or ask for a reassessment.
May 25, 2007 Good article nominee Listed
WikiProject Astronomy This article is within the scope of WikiProject Astronomy, which collaborates on articles related to astronomy, and WikiProject Astronomical Objects, which collaborates on articles related to astronomical objects, and WikiProject Physics, which collaborates on articles related to physics.
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Contents

[edit] Supernova

The seed for this article came from the FA'd supernova page. The later had reached 88 Kb, so material needed to be split off. The Type Ia section on the supernova article will be written summary-style. — RJH (talk) 19:39, 1 May 2007 (UTC)

Summary-style rewrite completed. — RJH (talk) 18:47, 25 May 2007 (UTC)

[edit] Remnant

In the "Consensus model" page it first stated that the star is unbound. But a subsequent addition said that:

As a general rule, the system will remain bound if the remnant is heavier than one half of the original total system mass. If not, the companion will evolve into a runaway star.[1]

So this is contradictory to me. This reference states that the most favored scenario is the "complete disintegration of a CO white dwarf". Was this a confusion with core-collapse supernovae? — RJH (talk) 15:54, 24 May 2007 (UTC)

[edit] GA on hold

I have reviewed this article according to the GA criteria and have put the article on hold at this time until the following issues are addressed.

  1. "The current view is that this limit is never actually attained, however, so that collapse is never initiated." What is the current view? From a particular group? Generally accepted by all astronomers? Specify a little here.
    • I specified that this is the viewpoint among astronomers who model these explosions. Also I added in an approximate mass and another reference.
  2. "Regardless of the exact details of nuclear burning, it is generally accepted that a substantial fraction of the carbon and oxygen in the white dwarf is burned into heavier elements within a period of only a few seconds,[7] raising the internal temperature to billions of degrees." Either expand on this or incorporate it into another paragraph. Single sentences shouldn't stand alone.
    • Merged.
  3. "A second possible, but much less likely, mechanism for triggering a Type Ia supernova is the merger of two white dwarfs, with the combined mass exceding the Chandrasekhar limit." Exceeding is spelled wrong.
    • Fixed.
  4. "The white dwarf companion could also accrete matter from other types of companions, including a main sequence star (if the orbit is sufficiently close)." Again, expand or incorporate into another paragraph.
    • Done.
  5. Somewhere in the article, maybe in its own section, include the differences between a Ia supernova and a Type II supernova. Also add Type II supernova to the See Also section.
    • I added a sentence about core-collapse supernovae, but really the supernova article is where the two are compared.
  6. See if there are any other external links that are relevant and informative that could be added. Make sure they comply with WP:EL.
    • Seems a bit of a stretch, but I added two more. :-)

This isn't too much to fix, and I'll leave the article on hold for up to seven days. If you have any questions or when you are done addressing the above issues, let me know on my talk page and I'll get back to you as soon as I can. --Nehrams2020 18:41, 23 May 2007 (UTC)

Thank you for the review. I've attempted to address the outstanding issues. — RJH (talk) 18:40, 25 May 2007 (UTC)

[edit] GA passed

I have reviewed this article according to the GA criteria and have passed this article. Good work on addressing the above issues so quickly. The article is very informative and it was interesting read. I'll probably let another editor review Type II supernova just so there is a difference of opinion in the reviews. Make sure that the article maintains its high quality, and ensure than all new information is properly sourced. As a side note, are there any WikiProjects that this article falls under? If so, please add them to the top, as I'm sure they want to keep track of their GA articles. If you get the chance, please consider helping with the current drive to remove the backlog at GAC. Even if you review just one or two articles, the review waiting time will be reduced for new candidates. Keep up the good work, and I hope you continue to improve the quality of articles on Wikipedia! --Nehrams2020 18:50, 25 May 2007 (UTC)

Thanks again. — RJH (talk) 16:09, 26 May 2007 (UTC)

[edit] Supernova via IMBH

The following article discusses an unusual mechanism for igniting Type 1a supernovae through tidal disruption by an IMBH in a globular cluster.

It should be interesting to see if this is observationally confirmed.—RJH (talk) 19:47, 30 January 2008 (UTC)

[edit] Inconsistency in source of max light output?

Under "Light curve", the text says that "Near the time of maximum luminosity, the spectrum contains lines of intermediate-mass elements from oxygen to calcium" while "The radioactive decay of nickel-56 through cobalt-56 to iron-56 produces high-energy photons which dominate the energy output of the ejecta at intermediate to late times." However the picture says "The peak is primarily due to the decay of Nickel (Ni), while the later stage is powered by Cobalt (Co)." This seems contradictory to me regarding the role of Nickel---or at least confusing enough to warrant clarification. -- Spireguy (talk) 14:20, 30 April 2008 (UTC)

Are you confused about how the "intermediate to late times" statement relates to the graph curve? Otherwise, the first statement shows that the Ni-56 decay produces Co-56, which then decays. Hence they are consistent chronologically.—RJH (talk) 16:21, 30 April 2008 (UTC)

I'll clarify: the confusion is about what generates the peak energy. The text seems to say that elements from Oxygen to Calcium are responsible for the emissions near the peak. The picture says that the peak is due to Nickel. That would be contradictory. Perhaps the Oxygen through Calcium lines are absorption lines, due to the outer layers filtering the Nickel-generated emissions? Or maybe they are emission lines, so that they are contributing to the output, but the Nickel-generated emissions are still predominant? Either would make sense logically, but whatever is going on, I think it needs to be spelled out. -- Spireguy (talk) 03:09, 1 May 2008 (UTC)