Quarks and Antiquarks in the Nucleon

My earliest research in physics was in a particle physics collaboration at FermiLab.  The idea of the experiment I worked on from 1994 to 1997 (FermiLab E866) was to study the nucleon sea—a tiny but turbulent region bubbling with quantum activity inside a proton or neutron, where quark-antiquark pairs can appear for an instant before annihilating each other.

In particular, we made a precise measurement of how often pairs of “up” quarks are produced, relative to how often “down” quarks are produced in the nucleon sea, and showed that there was a statistically significant difference which particle physics theory could not account for.


While I went on to more mathematical and theoretical work, I have colleagues who continued research along these lines, and it’s still nice to look in and see what’s going on in the area I started out in.

Fortunately for me, there’s a nice new review article on the subject of quark-antiquark pairs in the nucleon, written by two of my senior colleagues from E866, Don Geesaman and Paul Reimer:

D. F. Geesaman and P. E. Reimer, The Sea of Quarks and Antiquarks in the Nucleon: a Review, https://arxiv.org/abs/1812.10372

It’s nicely written, and explains the state of the art in sea quark physics from both the experimental and theoretical sides.

Tags: ,

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: