Measurement of the helicity asymmetry E for the γ⃗ p⃗ → pπ 0 reaction in the resonance region
DOI
10.48550/arXiv.2305.08616
Abstract
The double-spin-polarization observable 𝔼 for γ⃗p⃗→pπ0 has been measured with the CEBAF Large Acceptance Spectrometer (CLAS) at photon beam energies Eγ from 0.367 to 2.173 GeV (corresponding to center-of-mass energies from 1.240 to 2.200 GeV) for pion center-of-mass angles, cosθc.m.π0, between -0.86 and 0.82. These new CLAS measurements cover a broader energy range and have smaller uncertainties compared to previous CBELSA data and provide an important independent check on systematics. These measurements are compared to predictions as well as new global fits from The George Washington University, Mainz, and Bonn-Gatchina groups. Their inclusion in multipole analyses will refine our understanding of the single-pion production contribution to the Gerasimov-Drell-Hearn sum rule and improve the determination of resonance properties.
Document Type
Article
Publication Date
5-15-2023
Recommended Citation
Kim, C. W., others (2023). Measurement of the helicity asymmetry E for the γ⃗ p⃗ → pπ 0 reaction in the resonance region. Eur. Phys. J. A, 59(9), article 217.
