Two photon exchange with nuclei from $$e^+/e^-$$ e + / e - elastic cross section ratios
Abstract Hadronic box diagrams pose a significant source of radiative corrections to lepton scattering and $$\beta $$ β -decay measurements,...
| Main Authors: | , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
Springer Berlin Heidelberg
2022
|
| Online Access: | https://hdl.handle.net/1721.1/141028 |
| _version_ | 1811091659778162688 |
|---|---|
| author | Kutz, T. Schmidt, A. |
| author2 | Massachusetts Institute of Technology. Laboratory for Nuclear Science |
| author_facet | Massachusetts Institute of Technology. Laboratory for Nuclear Science Kutz, T. Schmidt, A. |
| author_sort | Kutz, T. |
| collection | MIT |
| description | Abstract
Hadronic box diagrams pose a significant source of radiative corrections to lepton scattering and
$$\beta $$
β
-decay measurements, yet their calculation remains highly model-dependent. Two-photon exchange is a box diagram generally relevant to most lepton scattering experiments, and is directly detectable via multiple observables. Single-spin asymmetries (SSA) are sensitive to the imaginary part of the TPE amplitude, while the ratio of
$$e^+/e^-$$
e
+
/
e
-
elastic scattering cross sections is sensitive to the real part of the TPE amplitude. While SSA measurements have been reported for several complex nuclei, measurements of the
$$e^+/e^-$$
e
+
/
e
-
ratio exist only for the proton. Proposed here is a measurement of the
$$e^+/e^-$$
e
+
/
e
-
ratio on
$$^4$$
4
He, a feasible nuclear target for which the ratio’s deviation from unity due to TPE is expected to be on order of 1–2%. Choosing a low Z nucleus minimizes Coulomb distortions, which could greatly overwhelm TPE for heavier nuclei. The proposed 19-day program, including measurements at three kinematic settings between
$$0.3< Q^2 < 0.4$$
0.3
<
Q
2
<
0.4
GeV
$$^2$$
2
, would be made possible by the addition of a positron source at Jefferson Lab. |
| first_indexed | 2024-09-23T15:05:54Z |
| format | Article |
| id | mit-1721.1/141028 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T15:05:54Z |
| publishDate | 2022 |
| publisher | Springer Berlin Heidelberg |
| record_format | dspace |
| spelling | mit-1721.1/1410282023-01-20T16:51:46Z Two photon exchange with nuclei from $$e^+/e^-$$ e + / e - elastic cross section ratios Kutz, T. Schmidt, A. Massachusetts Institute of Technology. Laboratory for Nuclear Science Abstract Hadronic box diagrams pose a significant source of radiative corrections to lepton scattering and $$\beta $$ β -decay measurements, yet their calculation remains highly model-dependent. Two-photon exchange is a box diagram generally relevant to most lepton scattering experiments, and is directly detectable via multiple observables. Single-spin asymmetries (SSA) are sensitive to the imaginary part of the TPE amplitude, while the ratio of $$e^+/e^-$$ e + / e - elastic scattering cross sections is sensitive to the real part of the TPE amplitude. While SSA measurements have been reported for several complex nuclei, measurements of the $$e^+/e^-$$ e + / e - ratio exist only for the proton. Proposed here is a measurement of the $$e^+/e^-$$ e + / e - ratio on $$^4$$ 4 He, a feasible nuclear target for which the ratio’s deviation from unity due to TPE is expected to be on order of 1–2%. Choosing a low Z nucleus minimizes Coulomb distortions, which could greatly overwhelm TPE for heavier nuclei. The proposed 19-day program, including measurements at three kinematic settings between $$0.3< Q^2 < 0.4$$ 0.3 < Q 2 < 0.4 GeV $$^2$$ 2 , would be made possible by the addition of a positron source at Jefferson Lab. 2022-03-07T14:13:53Z 2022-03-07T14:13:53Z 2022-02-28 2022-03-06T04:10:54Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/141028 The European Physical Journal A. 2022 Feb 28;58(3):36 PUBLISHER_CC en https://doi.org/10.1140/epja/s10050-022-00682-1 Creative Commons Attribution https://creativecommons.org/licenses/by/4.0/ The Author(s) application/pdf Springer Berlin Heidelberg Springer Berlin Heidelberg |
| spellingShingle | Kutz, T. Schmidt, A. Two photon exchange with nuclei from $$e^+/e^-$$ e + / e - elastic cross section ratios |
| title | Two photon exchange with nuclei from $$e^+/e^-$$ e + / e - elastic cross section ratios |
| title_full | Two photon exchange with nuclei from $$e^+/e^-$$ e + / e - elastic cross section ratios |
| title_fullStr | Two photon exchange with nuclei from $$e^+/e^-$$ e + / e - elastic cross section ratios |
| title_full_unstemmed | Two photon exchange with nuclei from $$e^+/e^-$$ e + / e - elastic cross section ratios |
| title_short | Two photon exchange with nuclei from $$e^+/e^-$$ e + / e - elastic cross section ratios |
| title_sort | two photon exchange with nuclei from e e e e elastic cross section ratios |
| url | https://hdl.handle.net/1721.1/141028 |
| work_keys_str_mv | AT kutzt twophotonexchangewithnucleifromeeeeelasticcrosssectionratios AT schmidta twophotonexchangewithnucleifromeeeeelasticcrosssectionratios |