My research is focused on the development and application of effective field theories to quantum chromodynamics, with the ultimate goal of achieving a deeper understanding of the strong interactions that
underlie nuclear physics. Measurements of QCD made by contemporary nuclear and particle experiments are often complicated by the presence of multiple disparate energy scales which obscure the relevant physics. The effective theories I develop and work with provide a powerful organizing tool for systematically separating different scales,
resulting in a simpler and more predictive framework. I have worked on non-relativistic effective theories of the strong interactions (NRQCD), an effective theory of heavy nucleons coupled to pions, heavy-quark effective theory (HQET), and soft collinear effective theory (SCET). Broadly I focus on the development and application of effective field theories (EFTs) to quantum chromodynamics (QCD), with the ultimate goal of achieving a deeper understanding of the strong interactions. My work spans a broad spectrum of the strong interactions. Highlights of my past achievements include using nonrelativistic QCD (NRQCD) to study the production of bound states of an heavy quark and an heavy antiquark (quarkonium) at high energy colliders; using an EFT of two nucleon systems with perturbative pions (aka KSW) to compute scattering phase shifts to NNLO in a chiral expansion; developing soft collinear effective theory (SCET) as a tool to sum Sudakov logarithms and to factorize high energy hadronic collisions; developing X-EFT to study molecular states near threshold.
My current research, as well as my plans for the next couple of years are heavily focused on using SCET in a variety of contexts. A major portion of my current research effort is related to the generalized structure of the nucleon. In addition,
I have returned to my roots to take a second look at quarkonium production in high energy hadronic collisions, and I continue to work on the X(3872) using X-EFT.
OJI award 2005
Bauer, C.W., Fleming, S., Pirjol, D., Stewart, I.W. An Effective field theory for collinear and soft gluons: Heavy to light decays. Phys. Rev. D63 (2001) 114020.
Fleming, S., Kusunoki, M., Mehen, T., van Kolck, U. Pion interactions in the X(3872). Phys. Rev. D76 (2007) 034006.
Fleming, S., Leibovich, A.K., Mehen, T., Rothstein, I.Z. The Systematics of Quarkonium Production at the LHC and Double Parton Fragmentation. Phys.Rev. D86 (2012) 094012.
Fleming, S., Zhang, O. Rapidity Divergences and Deep Inelastic Scattering in the Endpoint Region. e-Print: arXiv:1210.1508 [hep-ph]
Fleming, S. The role of Glauber Exchange in Soft Collinear Effective Theory and the Balitsky-Fadin-Kuraev-Lipatov Equation. Phys. Lett. B 735, 266 (2014).