Supernovae

Hello.
Where I can search a good descrition of the supernovae phenomena (type I and
II)?
Thank

"Marco Siso" wrote in message
...
Hello.
Where I can search a good descrition of the supernovae phenomena (type I
and
II)?
Thank


Hi,

If my translate module (left of my menu) could help you translating my
French pages, try this
http://www.astrosurf.com/lombry/diversite-etoiles3.htm

Thierry

"Marco Siso" wrote in message
...
Hello.
Where I can search a good descrition of the supernovae phenomena (type I
and
II)?
Thank


Hi,

If my translate module (left of my menu) could help you translating my
French pages, try this
http://www.astrosurf.com/lombry/diversite-etoiles3.htm

Thierry

Marco Siso wrote:

Hello.
Where I can search a good descrition of the supernovae phenomena (type I and
II)?

See: http://www.google.com/search?q=supernovae+types

Marco Siso wrote:

Hello.
Where I can search a good descrition of the supernovae phenomena (type I and
II)?

See: http://www.google.com/search?q=supernovae+types

Marco Siso wrote:

Hello.
Where I can search a good descrition of the supernovae phenomena (type I and
II)?
Thank

Supernovae--No quick answers without making blunders.

o Type Ia -- little or hydrogen in the spectra
o Type Ia -- matter falling onto a white dwarf
mass exceeding Chandrasekhar Limit

o Type II -- significant hydrogen in the spectra
o Type II -- involves core collase of massive stars
core mass exceeding Chandrasekhar Limit

For some resource material see:
http://www.edu-observatory.org/eo/white_dwarfs.html
http://www.edu-observatory.org/eo/black_holes.html

When looking at the Universe about us:

o We find mostly hydrogen and helium. Why--we have compelling
evidence drawn from many corners of astronomy and physics that
the universe evolved from a hotter dense state. When one models
the hotter denser state of about the first few hundred seconds,
particle physics predicts that roughly 75% hydrogen and 24%
helium will be formed from the primordial soup. Observation
confirms these abundance's.

o We have a good understanding of nucleosynthesis of elements
through the iron group, including carbon, nitrogen and oxygen.
I refer you to to Lang (1999), "Astronomical Formulae Vol. I",
Sec 4.4, "Nucleosynthesis of the Elements", pp 402-432.

o We have some understanding of creation of elements with atomic
number greater than the iron group. The computing power and
detail during the relativistic collapse of stellar structures
is a tough problem for details... no hint whatsoever that these
processes are incorrect for the nucleosynthesis of the observed
heavier elements.

Ref: "Astronomical Formulae" Lang 1998 pg 103

"We now realize that elements heavier than iron cannot be
produced in successive static burning stages within stars.
This is because any nuclear reaction involving the iron
group of nuclei, with atomic weight A ~ 56, cannot provide
fuel for the thermonuclear fires that support a star and make
it shine. Instead, the iron-group elements act like seeds for
the synthesis of heavier elements by neutron capture. Such
processes were first suggested by George Gamow for nonequilibrium
nucleosynthesis during the early stages of the expansion of
the Universe (Gamow, 1948; Alpher, Bethe and Gamow, 1948), and
applied to the later stages of stellar evolution by Burbidge,
Burbidge, Fowler and Hoyle (1957), often called B²FH, and
independently by Cameron (1957)".

"Double-peaked features in the abundance curves Relative Abundance
vs Atomic Weight] (Fig. 5.27) indicate that two neutron capture
processes, called the r-process and the s-process, must synthesize
elements with atomic weights A greater than 60. The rapid (r- process)
neutron capture occurs on time scales of about 100 seconds, which
is rapid (r) compared to electron beta decay in the synthesis
networks, while the s-process is much slower (s), occurring over
scales of 10² to 10^5 years. All naturally occurring radioactive
elements with A 209, including the long-lived uranium, U, and
thorium, Th, parents, 238U, 235U and 232Th, require the r-process,
which builds beyond mass 238 to nuclei that decay back to these
radioactive parents. The r-process probably occurs during stellar
explosions, called supernovae, that rapidly provide a large neutron
flux with a short duration".

Marco Siso wrote:

Hello.
Where I can search a good descrition of the supernovae phenomena (type I and
II)?
Thank

Supernovae--No quick answers without making blunders.

o Type Ia -- little or hydrogen in the spectra
o Type Ia -- matter falling onto a white dwarf
mass exceeding Chandrasekhar Limit

o Type II -- significant hydrogen in the spectra
o Type II -- involves core collase of massive stars
core mass exceeding Chandrasekhar Limit

For some resource material see:
http://www.edu-observatory.org/eo/white_dwarfs.html
http://www.edu-observatory.org/eo/black_holes.html

When looking at the Universe about us:

o We find mostly hydrogen and helium. Why--we have compelling
evidence drawn from many corners of astronomy and physics that
the universe evolved from a hotter dense state. When one models
the hotter denser state of about the first few hundred seconds,
particle physics predicts that roughly 75% hydrogen and 24%
helium will be formed from the primordial soup. Observation
confirms these abundance's.

o We have a good understanding of nucleosynthesis of elements
through the iron group, including carbon, nitrogen and oxygen.
I refer you to to Lang (1999), "Astronomical Formulae Vol. I",
Sec 4.4, "Nucleosynthesis of the Elements", pp 402-432.

o We have some understanding of creation of elements with atomic
number greater than the iron group. The computing power and
detail during the relativistic collapse of stellar structures
is a tough problem for details... no hint whatsoever that these
processes are incorrect for the nucleosynthesis of the observed
heavier elements.

Ref: "Astronomical Formulae" Lang 1998 pg 103

"We now realize that elements heavier than iron cannot be
produced in successive static burning stages within stars.
This is because any nuclear reaction involving the iron
group of nuclei, with atomic weight A ~ 56, cannot provide
fuel for the thermonuclear fires that support a star and make
it shine. Instead, the iron-group elements act like seeds for
the synthesis of heavier elements by neutron capture. Such
processes were first suggested by George Gamow for nonequilibrium
nucleosynthesis during the early stages of the expansion of
the Universe (Gamow, 1948; Alpher, Bethe and Gamow, 1948), and
applied to the later stages of stellar evolution by Burbidge,
Burbidge, Fowler and Hoyle (1957), often called B²FH, and
independently by Cameron (1957)".

"Double-peaked features in the abundance curves Relative Abundance
vs Atomic Weight] (Fig. 5.27) indicate that two neutron capture
processes, called the r-process and the s-process, must synthesize
elements with atomic weights A greater than 60. The rapid (r- process)
neutron capture occurs on time scales of about 100 seconds, which
is rapid (r) compared to electron beta decay in the synthesis
networks, while the s-process is much slower (s), occurring over
scales of 10² to 10^5 years. All naturally occurring radioactive
elements with A 209, including the long-lived uranium, U, and
thorium, Th, parents, 238U, 235U and 232Th, require the r-process,
which builds beyond mass 238 to nuclei that decay back to these
radioactive parents. The r-process probably occurs during stellar
explosions, called supernovae, that rapidly provide a large neutron
flux with a short duration".

On Wed, 18 Feb 2004 19:37:14 GMT, "Marco Siso" wrote:

Hello.
Where I can search a good descrition of the supernovae phenomena (type I and
II)?
Thank

Look for a book called Extreme Stars author is James Kaler and it's
published by Cambridge University Press in 2001.
It covers the developement of all star types and has some very interesting
chapters on Novas and Wolf-Rayet type stars.

On Wed, 18 Feb 2004 19:37:14 GMT, "Marco Siso" wrote:

Hello.
Where I can search a good descrition of the supernovae phenomena (type I and
II)?
Thank

Look for a book called Extreme Stars author is James Kaler and it's
published by Cambridge University Press in 2001.
It covers the developement of all star types and has some very interesting
chapters on Novas and Wolf-Rayet type stars.

"Marco Siso" wrote:

Where I can search a good descrition of the supernovae
phenomena (type I and II)?

Well, I happen to know that there isn't one to be found at
www.google.com (you must have checked already too). Nor will you find
a normal astronomy textbook any good (some will dispute this of
course, but we know better, don't we?).

Maybe at Tiffany's? http://www.tiffany.com/ Ignore the jewellery
stuff: thats just the cover story for the high-end astrophysical
research carried out in the back rooms.