Term
white dwarf
neutron star
black hole |
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Definition
0.1-1.4Mo electron degeneracy
1.4-2.0Mo neutron degeneracy
2.0Mo+ no relativity |
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Term
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Definition
| surface where time goes to inifinity |
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Term
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Definition
| spinning neutron star with a magnetic field |
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Term
| List the basic fusion cycles and how they work. |
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Definition
p-p(proton-proton) 4H->He+energy
3a(triple alpha) 3He->C+energy
CNO(cardon-nitrogen-oxygen) C+4H->C+He |
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Term
define type 1 nova
define type 2 nova |
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Definition
a nova associated with 1.4Mo stars
a nova associated with high mass stars |
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Term
define population 1
define population 2 |
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Definition
stars with high elemental abundance
stars with low elemental abundance |
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Term
| What will kill you in even horizon? |
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Definition
-differential gravity-gravity near even horizon is very strong
-tidal effect-blood rushes in one direction
-time dilation-time goes to infinity |
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Term
| Discuss why white holes are needed. |
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Definition
| So that a blackhole's infinite depth pops out back into the real space through a white hole |
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Term
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Definition
| when several fusion cycles are operating at the same time |
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Term
| Discuss what happens in a type 2 nova. |
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Definition
| The outgoing pressure wave is conatined until it equal the gravity pressure. Once the gravity pressure is exceded all fusion/fission stops. This allows atoms of all values to be expelled into space. This explains the variation of elemental abundance in stars. |
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Term
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Definition
| when a binary pair exchanges mass causing multiple novae |
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Term
| Discuss how millisec pulsars form. |
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Definition
| I1w1=I2w2 Thus a star goes grom aprox 100,000 miles to aprox 10 miles. This gives a velocity=millisec. If the star has a magnetic field it also increases. Observations show that the pulsar slows as predicted. |
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Term
| Discuss how pulsars confims relativity. |
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Definition
| Pulsars are verty accurate clocks. A binary pulsar ticks at rates based on their distance from eachother the variation is exactly as predicted by relativity. |
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Term
| Heisenberg uncertainty principle |
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Definition
| deltaE*deltat>=h for something to be observable |
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Term
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Definition
| something with a deltaE*deltat |
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Term
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Definition
| the energy that should be observed by virtual particles near an event horizon |
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Term
| Find the maximum size of a virtual electron pair |
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Definition
| 2mec^2deltat<2 2mec/h=1/d |
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Term
| Draw the light curve of a type 2 nova and explain. |
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Definition
| The total light cirve is the sum of the thermal and radioactive energy. Since Ni56 decays quickly you get a kink as the light curve becomes 100% thermal |
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Term
| Discuss how a type 2 nova explodes. |
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Definition
| Once an Fe core forms both fusion and fission cycles absorb energy. Thus the core cools and upper levels fall inward. The upper layers fall into the high temperature core. There is an explosion. The outgoing pressure wave hits the in falling fuel thus producing a massive energy output. |
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Term
| Draw a diagram and explain one version of type 1 novae found in binary pairs. |
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Definition
| The white dward takes mass from the red giant. At 1.4Mo the chandrasaker limit is reached and the star nova. |
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Term
| Draw a diagram and explain pulsars. |
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Definition
| The spinning magnetic field accelerates charged particles and they radiate |
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Term
| How does a Neutron star form? |
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Definition
| When a medium-size star runs out of fuel (hydrogen to fuse into helium), it will collapse on itself. It has a large enough mass that it can push past the resistance from electron degeneracy pressure. When it collapses more, it will get stopped by neutron degeneracy pressure. It will settle at a star that is about 20 kilometers in diameter. The star fuses protons with electrons, and these form neutrons |
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Term
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Definition
| A standard candle is a class of astrophysical objects, such as supernovae or variable stars, which have known luminosity due to some characteristic quality possessed by the entire class of objects. Thus, if an extremely distant object can be identified as a standard candle then the absolute magnitude M (luminosity) of that object is known. Knowing the absolute magnitude, the distance D (in cm) can be calculated from the apparent magnitude m as shown in the formula below. |
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Term
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Definition
| (carbon-nitrogen-oxygen) C+4H->C+He |
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