Progress in plasma wakefield acceleration for positrons

Three new studies show the promise and challenge of using plasma wakefield acceleration to build a future electron-positron collider. Matter is known to exist in four different states: solid, liquid, gas or--under circumstances such as very high temperatures--plasma. A plasma is an ionized gas, a gas with enough energy that some of its atoms have lost their electrons, and those negatively charged electrons are floating along with the now positively charged nuclei they left behind. If you send tw...