MBuzaTalk2.ppt

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Neutron Stars
By: Matthew Buza
Star Power
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Importance of Stars and their role
in the universe.
Overview of all stars, and basic
characteristics.
Stellar Evolution: Start  finish
Path to a Neutron Star.
Further work being done.
Stars?
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Star Characteristics are given by:
 Luminosity
 Ave. Mass
 Ave. Diameter
Which all determines Main
Sequence Time.
 Ex. The sun is a
G2(spectoral class) and
has a main sequence time
of 12 billion years.
Stellar Evolution
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Laws same here as they are on other
planets, stars, universe.
Gravity is the same thing that keeps
you on the ground, and the earth going
around the sun.
We are chemically the same material
as planets, stars.
Important to understand the world
around us.
Exploring here on earth workings of
stars we understand better the cosmos
and ourselves.
Understand the basic principles that
govern our world and us.
Nothing Wrong With Second Best
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Not just the stars we should study, but the by products of them.
Basically, we are looking at the competition of Gravity vs. everything
else( kinetic effects, nuclear forces, degeneracy's, electro-magnetic)
Normal stars are fighting with Hydrodynamic pressure, and radiation
pressure.
But in by-products we see both electron and neutron degeneracy’s,
along with neutrino pressures. Where density is the dominating
factor.
Mainly, White Dwarfs, Neutron Stars, and Black holes.
The Touch of God
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Supernova
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Star begins to fuse iron, which
eats up energy.
Causes the star to contract,
gravity taking over
Varying densities causes pressure
build up, and then the ‘bounce’
(degenerate core), the star
violently ejects large amounts of
the star into space.
Small Stellar objects are left
behind, depending on the core
that is left (mass).
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This dictates the finally product,
governed by the Chandrasekar
limit (1.44 sol) , which is the
maximum mass of a white dwarf
star.
Neutron Stars are generally 1.4-3
solar masses.
Neutron Stars
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From massive White
Dwarf stars to Neutron
stars
Cooling of the WDS, forms a
Fe lattice, with intermittent
heavier elements spread
throughout.
 Supported by Electron
degeneracy, has a completely
free degenerate electron gas
If Fermi energy exceeds the
Neutron-Proton mass difference,
new exothermic reaction occurs,
Reverse Beta-Decay
e + p  n + ve
Supported by Neutron Degeneracy.
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Neutron Stars
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From White Dwarf star to Neutron
star
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Density from 1000 tons per cubic
inch to 10 billion tons per cubic
inch.
From 10,000 miles in diameter to
about 10 miles.
What is being worked on?
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‘Pasta’ simulations here at FSU.
 Studying multiple
densities, running
simulations and looking for
‘clumping’ of the protons.
 Exploring these
characteristics could help
to describe many of the
characteristics of the
neutron stars
 Surface features,
starquakes, spinning up or
down of the star (pulsars).
 We hope that this could
open up some explanation
for why things happen.
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