NRQED and next-to-leading hyperfine splitting in positronium

Jun, 1997
23 pages
Published in:
  • Phys.Rev.D 56 (1997) 8053-8061
e-Print:
Report number:
  • MCGILL-97-10

Citations per year

1997200420112018202501234567
Abstract:
We compute the next-to-leading, O(m alpha^5), contribution to the hyperfine splitting in positronium within the framework of NRQED. When applied to the ground state, our calculation reproduces known results, providing a further test of NRQED techniques. Besides providing a very simple method of calculation of the standard result, we also obtain new expressions for excited states of positronium with negligible additional effort. Our calculation requires the complete next-to-leading matching of the lowest-dimension NRQED four-fermi couplings, which we publish here for the first time.
  • 31.30.Jv
  • 31.15.Md
  • 12.20.Ds
  • 11.10.St
  • positronium: energy levels
  • positronium: hyperfine structure
  • positronium: excited state
  • quantum electrodynamics: nonrelativistic
  • effective Lagrangian
  • Feynman graph: higher-order