compact objects Flashcards
1
Q
white dwarfs
A
- remaining core of low mass stars
- hot and faint
- supported by electron degeneracy pressure
- cool and dim with time
2
Q
what is thermal pressure
A
- like air in ballon
- porp to heat
3
Q
what is elec degeneracy pressure
A
- electrons pushed into their lowest energy states
4
Q
size of white dwarf thats mass of sun
A
earth
more mass = more dense = smaller
5
Q
mass limit of white dwarf
A
1.4 mass of sun, because of speed of electrons
6
Q
2 types of supernova
A
- massive star
- white dwarf
7
Q
massive star supernova
A
iron core reaches WD limit and collapses
8
Q
WD super nova
A
carbon fusion begins as WD in binary system reaches limit
9
Q
nova vs supernova
A
nova = WD left intact
supernova = 100x more bright
10
Q
what is neutron star
A
- ball of neutrons left by a supernova
- size of small city
- discovered by radio tele
11
Q
what is pulsar
A
- spining neutron star
- beas radiation along mag axis (not algined with rot. axis)
12
Q
what is a black hole
A
- presure fails to stop grav collapse
- all mass crushed to tiny poiint
13
Q
what is the singularity
A
the single point where all matter is crushed to
14
Q
how do we measure grav waves
A
laser inferometry
15
Q
what happens when black holes or neutron stars merge
A
produces grav waves
