Lecture #14

Plasma temperature limit

Below 15,000 or above 2 million K

Cygnus X1: black hole candidate

Small light travel time (~0.01s)

Large mass (>5.3 Solar masses)

X-ray stars

High mass: Wolfe-Rayet

Low mass: pulsars, Type Ia

X-ray objects lie in Galactic plane

Supernova classification scheme

Lecture #15

Gravity waves

The effect of gravity travel in waves propagating at the speed of light

Detection of gravity waves

Pulsars

Averaged spectrum is periodic

Lighthouse model

Material funneled down by B field

Produces bright spot on neutron star

Rotates so spot phases in & out of view

Lecture #16

Gamma Ray Bursts

Short peak (~1MeV, lasts seconds)

Short tail (lasts 20-50s)

Falls off quickly at high E (~10MeV)

Falls off slowly at low E

Even distribution: cosmological

Neutron stars sheared apart by black hole, forming an accretion disk

Large amounts of mass drops into the black hole, producing neutrinos that burst through envelope: GRB