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Updated: Jun 22, 2026
In vivo Quantification of G Protein Coupled Receptor Interactions using Spectrally Resolved Two-photon Microscopy
Published on: January 19, 2011
Measurements of H-->D-->(gamma-->,pi) and implications for the convergence of the Gerasimov-Drell-Hern integral
S Hoblit1, A M Sandorfi, K Ardashev
1Department of Physics, University of Virginia, Charlottesville, Virginia 22901, USA. hoblit@bnl.gov
Abstract:
We report new measurements of inclusive pi production from frozen-spin HD for polarized photon beams covering the Delta(1232) resonance. These provide data simultaneously on both H and D with nearly complete angular distributions of the spin-difference cross sections entering the Gerasimov-Drell-Hearn (GDH) sum rule. Recent results from Mainz and Bonn exceed the GDH prediction for the proton by 22 microb, suggesting as yet unmeasured high-energy components. Our pi0 data reveal a different angular dependence than assumed in Mainz analyses and integrate to a value that is 18 microb lower, suggesting a more rapid convergence. Our results for deuterium are somewhat lower than published data, considerably more precise, and generally lower than available calculations.
