ALPACA 2 (IMAGE) DOE/Princeton Plasma Physics Laboratory Caption A schematic drawing of ALPACA, a new plasma measurement instrument that observes the light of neutral atoms to determine their density. Credit David Mauzey Usage Restrictions N/A License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.