Two Winds

Two Winds

In today’s paper, Rezzolla and Kumar present a solution to the x-ray afterglow problem for the short gamma ray burst model. They show that x-rays can glow steadily for hours after the initial gamma ray emission due to the interactions of a slow and a fast wind.

Making Lanthanide Metals…or Not

Making Lanthanide Metals…or Not

There aren’t many places in the universe that you can find a bunch of free neutrons not already trapped inside a nucleus—except in neutron stars. Luckily, neutron stars in violent mergers with other neutron stars, or with black holes, tend to disperse a little bit of their matter into the interstellar medium. Tidal forces eject some matter as the two objects swing around each other in their final orbits. Then, if an accretion disk forms, winds blown off the surface of the disk disperse even more matter. Surman and her colleagues look at the nucleosynthesis that occurs in this latter process, and find something surprising.