Physicists Narrow Search for Solution to Proton Spin Puzzle
November 05, 2014
New RHIC results reveal that gluons make a significant contribution to spin, an important intrinsic particle property; transient sea quarks also play a role.
BNL press release at http://www.bnl.gov/newsroom/news.php?a=25112
How the spins of the building blocks of matter add up: Measurements from RHIC's STAR and PHENIX experiments reveal that gluons (yellow corkscrews) contribute about as much as quarks (red, green, and blue) to the overall spin of a proton. But there is still a mystery to explain what accounts for the rest of the "missing" spin.
Image/caption courtesy Brookhaven National Lab
BNL press release at http://www.bnl.gov/newsroom/news.php?a=25112
How the spins of the building blocks of matter add up: Measurements from RHIC's STAR and PHENIX experiments reveal that gluons (yellow corkscrews) contribute about as much as quarks (red, green, and blue) to the overall spin of a proton. But there is still a mystery to explain what accounts for the rest of the "missing" spin.
Image/caption courtesy Brookhaven National Lab