Brandon Manley

Physics Research Building, M2041

191 West Woodruff Ave

Columbus, OH 43210

Hi, I’m Brandon Manley, and I’m a theoretical physicist. I smash subatomic particles together on paper. I’m a PhD student and I currently work with Yuri Kovchegov. On this site, you can see my research works and cv.

My research is currently centered around the proton spin puzzle. I am mainly interested in the small Bjorken (x\,) behavior of the helicity parton distribution functions and the orbital angular momentum distributions. My research will help us understand what we should see from the Electron Ion Collider . My past research interests include dark matter production at the Large Hadron Collider (with the MilliQan collaboration), and CMS detector design.

selected publications

2023

Orbital Angular Momentum at Small \(x\,\)Revisited

Yuri V. Kovchegov, and Brandon Manley

Oct 2023

Abs arXiv

We revisit the problem of the small Bjorken-\(x\,\)asymptotics of the quark and gluon orbital angular momentum (OAM) distributions in the proton utilizing the revised small-\(x\,\)helicity evolution derived recently. We relate the quark and gluon OAM distributions at small \(x\,\)to the polarized dipole amplitudes and their (first) impact-parameter moments. To obtain the OAM distributions, we derive novel small-\(x\,\)evolution equations for the impact-parameter moments of the polarized dipole amplitudes in the double-logarithmic approximation (summing powers of \(\alpha_s \ln^2(1/x) \)with \(\alpha_s\,\)the strong coupling constant). We solve these evolution equations numerically and extract the leading large-\(N_c\), small-\(x\,\)asymptotics of the quark and gluon OAM distributions, which we determine to be in agreement with the existing results in the literature within the precision of our numerical evaluation. (Here \(N_c\,\)is the number of quark colors.) We also investigate the ratios of the quark and gluon OAM distributions to their helicity distribution counterparts in the small-\(x\,\)region.