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From: HVAC on 17 Mar 2010 09:12
An international team led by Yale University has, for the first time,
measured the mass of a type of supernova thought to belong to a unique
subclass and confirmed that it surpasses what was believed to be an
upper mass limit. Their findings, which appear online and will be
published in an upcoming issue of the Astrophysical Journal, could
affect the way cosmologists measure the expansion of the universe.

Cosmologists use Type Ia supernovae -- the violent explosions of dead
cores of stars called white dwarfs -- as a kind of cosmic ruler to
measure distances to the supernovae's host galaxies and, as such, to
understand the past and future expansion of the universe and explore
the nature of dark energy. Until recently, it was thought that white
dwarfs could not exceed what is known as the Chandrasekhar limit, a
critical mass equaling about 1.4 times that of the Sun, before
exploding in a supernova. This uniform limit is a key tool in
measuring distances to supernovae.

Since 2003, four supernovae have been discovered that were so bright,
cosmologists wondered whether their white dwarfs had surpassed the
Chandrasekhar limit. These supernovae have been dubbed the "super-
Chandrasekhar" supernovae.

Now Richard Scalzo of Yale, as part of a collaboration of American and
French physicists called the Nearby Supernova Factory, has measured
the mass of the white dwarf star that resulted in one of these rare
supernovae, called SN 2007if, and confirmed that it exceeded the
Chandrasekhar limit. They also discovered that the unusually bright
supernova had not only a central mass, but a shell of material that
was ejected during the explosion as well as a surrounding envelope of
pre-existing material. The team hopes this discovery will provide a
structural model with which to understand the other supermassive
supernovae.

Using observations from telescopes in Chile, Hawaii and California,
the team was able to measure the mass of the central star, the shell
and the envelope individually, providing the first conclusive evidence
that the star system itself did indeed surpass the Chandrasekhar
limit. They found that the star itself appears to have had a mass of
2.1 times the mass of the Sun (plus or minus 10 percent), putting it
well above the limit.

Being able to measure masses for all parts of the star system tells
the physicists about how the system may have evolved -- a process that
is currently poorly understood. "We don't really know much about the
stars that lead to these supernovae," Scalzo said. "We want to know
more about what kind of stars they were, and how they formed and
evolved over time."

Scalzo believes there's a good chance that SN 2007if resulted from the
merging of two white dwarfs, rather than the explosion of a single
white dwarf and hopes to study the other super-Chandrasekhar
supernovae to determine whether they, too, could have involved a
merger of two white dwarfs.

Theorists continue to explore how stars with masses above the
Chandrasekhar limit, which is based on a simplified star model, could
exist without collapsing under their own weight. Either way, a
subclass of supernovae governed by different physics could have a
dramatic effect on the way cosmologists use them to measure the
expansion of the universe.

"Supernovae are being used to make statements about the fate of the
universe and our theory of gravity," Scalzo said. "If our
understanding of supernovae changes, it could significantly impact of
our theories and predictions."
From: bert on 17 Mar 2010 09:29
On Mar 17, 9:12 am, HVAC <mr.h...(a)gmail.com> wrote:
> An international team led by Yale University has, for the first time,
> measured the mass of a type of supernova thought to belong to a unique
> subclass and confirmed that it surpasses what was believed to be an
> upper mass limit. Their findings, which appear online and will be
> published in an upcoming issue of the Astrophysical Journal, could
> affect the way cosmologists measure the expansion of the universe.
>
> Cosmologists use Type Ia supernovae -- the violent explosions of dead
> cores of stars called white dwarfs -- as a kind of cosmic ruler to
> measure distances to the supernovae's host galaxies and, as such, to
> understand the past and future expansion of the universe and explore
> the nature of dark energy. Until recently, it was thought that white
> dwarfs could not exceed what is known as the Chandrasekhar limit, a
> critical mass equaling about 1.4 times that of the Sun, before
> exploding in a supernova. This uniform limit is a key tool in
> measuring distances to supernovae.
>
> Since 2003, four supernovae have been discovered that were so bright,
> cosmologists wondered whether their white dwarfs had surpassed the
> Chandrasekhar limit. These supernovae have been dubbed the "super-
> Chandrasekhar" supernovae.
>
> Now Richard Scalzo of Yale, as part of a collaboration of American and
> French physicists called the Nearby Supernova Factory, has measured
> the mass of the white dwarf star that resulted in one of these rare
> supernovae, called SN 2007if, and confirmed that it exceeded the
> Chandrasekhar limit. They also discovered that the unusually bright
> supernova had not only a central mass, but a shell of material that
> was ejected during the explosion as well as a surrounding envelope of
> pre-existing material. The team hopes this discovery will provide a
> structural model with which to understand the other supermassive
> supernovae.
>
> Using observations from telescopes in Chile, Hawaii and California,
> the team was able to measure the mass of the central star, the shell
> and the envelope individually, providing the first conclusive evidence
> that the star system itself did indeed surpass the Chandrasekhar
> limit. They found that the star itself appears to have had a mass of
> 2.1 times the mass of the Sun (plus or minus 10 percent), putting it
> well above the limit.
>
> Being able to measure masses for all parts of the star system tells
> the physicists about how the system may have evolved -- a process that
> is currently poorly understood. "We don't really know much about the
> stars that lead to these supernovae," Scalzo said. "We want to know
> more about what kind of stars they were, and how they formed and
> evolved over time."
>
> Scalzo believes there's a good chance that SN 2007if resulted from the
> merging of two white dwarfs, rather than the explosion of a single
> white dwarf and hopes to study the other super-Chandrasekhar
> supernovae to determine whether they, too, could have involved a
> merger of two white dwarfs.
>
> Theorists continue to explore how stars with masses above the
> Chandrasekhar limit, which is based on a simplified star model, could
> exist without collapsing under their own weight. Either way, a
> subclass of supernovae governed by different physics could have a
> dramatic effect on the way cosmologists use them to measure the
> expansion of the universe.
>
> "Supernovae are being used to make statements about the fate of the
> universe and our theory of gravity," Scalzo said. "If our
> understanding of supernovae changes, it could significantly impact of
> our theories and predictions."

Over 25 years I have had my "credical mass theory" This finding my
theory predicts. So where is my Nobel?? TreBert
From: Sam Wormley on 17 Mar 2010 09:49
On 3/17/10 8:12 AM, HVAC wrote:
> Now Richard Scalzo of Yale

http://www.sciencedaily.com/releases/2010/03/100315162049.htm

"Scalzo believes there's a good chance that SN 2007if resulted from the
merging of two white dwarfs, rather than the explosion of a single white
dwarf and hopes to study the other super-Chandrasekhar supernovae to
determine whether they, too, could have involved a merger of two white
dwarfs".

From: HVAC on 17 Mar 2010 11:32

"bert" <herbertglazier79(a)msn.com> wrote in message
news:3556e025-d77a-4cf3-bd6d-779eddd4c8e9(a)g11g2000yqe.googlegroups.com...

Over 25 years I have had my "credical mass theory" This finding my
theory predicts. So where is my Nobel?? TreBert
~~~~~~~~~~~~~~~~~~~~~~~~~~~

What field do you want a Nobel in?

Spelling?


From: Hagar on 17 Mar 2010 11:28

"HVAC" <mr.hvac(a)gmail.com> wrote in message
news:hnqp5s$2ji$1(a)hvac.motzarella.org...
>
> "bert" <herbertglazier79(a)msn.com> wrote in message
> news:3556e025-d77a-4cf3-bd6d-779eddd4c8e9(a)g11g2000yqe.googlegroups.com...
>
> Over 25 years I have had my "credical mass theory" This finding my
> theory predicts. So where is my Nobel?? TreBert
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> What field do you want a Nobel in?
>
> Spelling?
>

Speeling


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