dorsal/arxiv
View SchemaNucleon-nucleon bremsstrahlung: An example of the impossibility of measuring off-shell amplitudes
| Authors | Harold W. Fearing |
|---|---|
| Categories | |
| ArXiv ID | nucl-th/9710061 |
| URL | https://arxiv.org/abs/nucl-th/9710061 |
| DOI | 10.1103/PhysRevLett.81.758 |
| Journal | Phys. Rev. Lett. 81 (1998) 758 |
Abstract
For nearly fifty years theoretical and experimental efforts in nucleon-nucleon bremsstrahlung (NN$\gamma$) have been devoted to measuring off-shell amplitudes and distinguishing among various NN potentials on the basis of their off-shell behavior. New experiments are underway, designed specifically to attain kinematics further off shell than in the past, and thus to be more sensitive to the off-shell behavior. This letter shows that, contrary to these expectations, and due to the invariance of the S-matrix under transformations of the fields, the off-shell NN amplitude is as a matter of principle an unmeasurable quantity in NN$\gamma$.
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"abstract": "For nearly fifty years theoretical and experimental efforts in\nnucleon-nucleon bremsstrahlung (NN$\\gamma$) have been devoted to measuring\noff-shell amplitudes and distinguishing among various NN potentials on the\nbasis of their off-shell behavior. New experiments are underway, designed\nspecifically to attain kinematics further off shell than in the past, and thus\nto be more sensitive to the off-shell behavior. This letter shows that,\ncontrary to these expectations, and due to the invariance of the S-matrix under\ntransformations of the fields, the off-shell NN amplitude is as a matter of\nprinciple an unmeasurable quantity in NN$\\gamma$.",
"arxiv_id": "nucl-th/9710061",
"authors": [
"Harold W. Fearing"
],
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"nucl-th",
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"doi": "10.1103/PhysRevLett.81.758",
"journal_ref": "Phys. Rev. Lett. 81 (1998) 758",
"title": "Nucleon-nucleon bremsstrahlung: An example of the impossibility of measuring off-shell amplitudes",
"url": "https://arxiv.org/abs/nucl-th/9710061"
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