nucleus: =1.2*10^14 gm cm^-3
mass: 1.4 Msun=2.8*10^33 gm
Therefore, volume: 2.3*10^19 cm^3, and radius=1.8*10^6cm = 18 km
Pressure is immense
Discovery in 1968
Unobservable, as they have no atmosphere
In hindsight, they should have realized this was false, neutron stars have large B field.
Therefore 10^10 Bsun ~10^12 gauss
Will be rotating rapidly
Electron at surface
if 10 rotations per second
v=10 * 2pR cm s^-1 = 1.2*10^8 cm s^-1=0.004c
E + 0.0004 * 10^12 = 0
E= 4* 10^9 e=4.8 * 10^-12
Fe >> Fg therefore rips particles from surface
This magnetosphere emits radio radiation from charged particles getting thrown around
We dont see all pulsars because we miss their beams
Crab Pulsar Shows
Slows down because radiation supplies energy
Glitches speed up suddenly "star quakes"
Neutron stars X-ray mass transfer
companion collapsed also
Laboratory for general relativity
gravitational radiation will cause system to spiral in
Recent studies first proof of gravitiational waves.
Mass Tansfer Binaries
What happens when stars get close together and one is a collapsed object? A lot!
From Keplers law:
P ~ R3/2
When stars get close enough to touch an orbit takes 3 hours to a few days
Formation of an accretion disk
Two things run the mass transfer: giant radius and mass loss, spiral together.