Document Type
Article
Publication Date
2025
DOI
10.1016/j.physletb.2025.139368
Publication Title
Physics Letters B
Volume
863
Pages
139368 (1-11)
Abstract
We measure the spin-density matrix elements (SDMEs) of the Δ⁺⁺ (1232) in the photoproduction reaction 𝛾p→π−Δ⁺⁺(1232) with the GlueX experiment in Hall D at Jefferson Lab. The measurement uses a linearly–polarized photon beam with energies from 8.2 to 8.8 GeV and the statistical precision of the SDMEs exceeds the previous measurement by three orders of magnitude for the momentum transfer squared region below 1.4 GeV². The data are sensitive to the previously undetermined relative sign between couplings in existing Regge-exchange models. Linear combinations of the extracted SDMEs allow for a decomposition into natural and unnatural–exchange amplitudes. We find that the unnatural exchange plays an important role in the low momentum transfer region.
Rights
© 2025 The Authors.
Published under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License.
Data Availability
Article states: "The data is available on HEPdata [26].
Original Publication Citation
Afzal, F., Akondi, C. S., Albrecht, M., Amaryan, M., Arrigo, S., Arroyave, V., Asaturyan, A., Austregesilo, A., Baldwin, Z., Barbosa, F., Barlow, J., Barriga, E., Barsotti, R., Barton, D., Baturin, V., Berdnikov, V. V., Black, T., Boeglin, W., Boer, M.,…Zihlmann, B. (2025). Measurement of spin-density matrix elements in δ++(1232) photoproduction. Physics Letters B, 863, 1-11, Article 139368. https://doi.org/10.1016/j.physletb.2025.139368
ORCID
0000-0002-5648-0256 (Amaryan), 0009-0003-5562-6465 (Viducic)
Repository Citation
Ayzal, F.; Akondi, C. S.; Albrecht, M.; Amaryan, M.; Arrigo, S.; Arroyave, V.; Asaturyan, A.; Austregesilo, A.; Baldwin, Z.; Barbosa, F.; Barlow, J.; Barringa, E.; Barsotti, R.; Barton, D.; Baturin, V.; Berdnikov, V. V.; Black, T.; Boeglin, W.; Boer, M.; Briscoe, W. J.; Britton, T.; Cao, S.; Chudakov, E.; Chung, G.; Cole, P. L.; Cortes, O.; Crede, V.; Dalton, M. M.; Darulis, D.; Deur, A.; Dobbs, S.; Dolgolenko, A.; Dugger, M.; Dzhygadlo, R.; Ebersole, D.; Edo, M.; Egiyan, H.; Erbora, T.; Eugenio, P.; Fabrizi, A.; Fanelli, C.; Fang, S.; Fitches, J.; Foda, A. M.; Furletov, S.; Gan, L.; Gao, H.; Gardener, A.; Gasparian, A.; Glazier, D. I.; Gleason, C.; Goryachev, V. S.; Grube, B.; Guo, J.; Guo, L.; Hernandez, J.; Hernandez, K.; Hoffman, N. D.; Hornidge, D.; Hou, G.; Hurck, P.; Hurley, A.; Imoehl, W.; Ireland, D. G.; Ito, M. M.; Jaegle, I.; Jarvis, N. S.; Jeske, T.; Jing, M.; Jones, R. T.; Kakoyan, V.; Kalicy, G.; Khachatryan, V.; Kourkoumelis, C.; LaDuke, A.; Larin, I.; Lawrence, D.; Lersch, D. I.; Li, H.; Liu, B.; Livingston, K.; Lolos, G. J.; Lorenti, L.; Lyubovitskij, V.; Ma, R.; Mack, D.; Mahmood, A.; Marukyan, H.; Matveev, V.; McCaughan, M.; McCracken, M.; Meyer, C. A.; Miskimen, R.; Mitchell, R. E.; Mizutani, K.; Neelamana, V.; Ng, L.; Nissen, E.; Oreśić, S.; Ostrovidov, A. I.; Papandreou, Z.; Paudel, C.; Pedroni, R.; Pentchev, L.; Peters, K. J.; Prathr, E.; Rakshit, S.; Reinhold, J.; Remington, A.; Ritchie, B. G.; Ritman, J.; Rodriguez, G.; Romanov, D.; Saldana, K.; Salgado, C.; Schadmand, S.; Schertz, A. M.; Scheuer, K.; Schick, A.; Schmidt, A.; Schumacher, R. A.; Schwiening, J.; Septian, N.; Sharp, P.; Shen, X.; Shepherd, M. R.; Sikes, J.; Smith, A.; Smith, E. S.; Sober, D. I.; Somov, A.; Somov, S.; Stevens, J. R.; Strakovsky, I. I.; Sumner, B.; Suresh, K.; Tarasov, V.V.; Taylor, S.; Teymurazyan, A.; Thiel, A.; Viducic, T.; Whitlatch, T.; Wickramaarachchi, N.; Wunderlich, Y.; Yu, B.; Zarling, J.; Zhang, Z.; Zhou, X.; and Zihlmann, B., "Measurement of Spin-Density Matrix Elements in Δ⁺⁺ (1232) Photoproduction" (2025). Physics Faculty Publications. 937.
https://digitalcommons.odu.edu/physics_fac_pubs/937