Measurement of Compton scattering at MAMI for the extraction of the electric and magnetic polarizabilities of the proton

Mornacchi, E. et al. (2022) Measurement of Compton scattering at MAMI for the extraction of the electric and magnetic polarizabilities of the proton. Physical Review Letters, 128(13), 132503. (doi: 10.1103/PhysRevLett.128.132503)

Abstract

A precise measurement of the differential cross sections d σ / d Ω and the linearly polarized photon beam asymmetry Σ 3 for Compton scattering on the proton below pion threshold has been performed with a tagged photon beam and almost 4 π detector at the Mainz Microtron. The incident photons were produced by the recently upgraded Glasgow-Mainz photon tagging facility and impinged on a cryogenic liquid hydrogen target, with the scattered photons detected in the Crystal Ball/TAPS setup. Using the highest statistics Compton scattering data ever measured on the proton along with two effective field theories (both covariant baryon and heavy-baryon) and one fixed- t dispersion relation model, constraining the fits with the Baldin sum rule, we have obtained the proton electric and magnetic polarizabilities with unprecedented precision: α E 1 = 10.99 ± 0.16 ± 0.47 ± 0.17 ± 0.34 , β M 1 = 3.14 ± 0.21 ± 0.24 ± 0.20 ± 0.35 ; in units of 10 − 4     fm 3 where the errors are statistical, systematic, spin polarizability dependent, and model dependent.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: MacGregor, Professor Douglas and Livingston, Dr Kenneth and Gardner, Mr Simon and Annand, Dr John and MULLEN, CHRISTOPHER and Glazier, Dr Derek and Powell, Ms Abby
• Authors: Mornacchi, E., Martel, P. P., Abt, S., Achenbach, P., Adlarson, P., Afzal, F., Ahmed, Z., Annand, J. R. M., Arends, H. J., Bashkanov, M., Beck, R., Biroth, M., Borisov, N., Braghieri, A., Briscoe, W. J., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dolzhikov, A. S., Downie, E. J., Drexler, P., Fegan, S., Gardner, S., Ghosal, D., Glazier, D. I., Gorodnov, I., Gradl, W., Günther, M., Gurevich, D., Heijkenskjöld, L., Hornidge, D., Huber, G. M., Käser, A., Kashevarov, V. L., Kay, S. J. D., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I. J. D., Manley, D. M., Miskimen, R., Mocanu, M., Mullen, C., Neganov, A., Neiser, A., Ostrick, M., Paudyal, D., Pedroni, P., Powell, A., Rostomyan, T., Sokhoyan, V., Spieker, K., Steffen, O., Strakovsky, I., Strub, T., Thiel, M., Thomas, A., Usov, Y. A., Wagner, S., Watts, D. P., Werthmüller, D., Wettig, J., Wolfes, M., and Zachariou, N.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Physical Review Letters
• Publisher: American Physical Society
• ISSN: 0031-9007
• ISSN (Online): 1079-7114
• Copyright Holders: Copyright © 2022 American Physical Society
• First Published: First published in Physical Review Letters 128(13): 132503
• Publisher Policy: Reproduced in accordance with the publisher copyright policy

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
170610		Glasgow nuclear physics consolidated grant	David Ireland	Science and Technology Facilities Council (STFC)	ST/L005719/1	P&S - Physics & Astronomy
301379		Nuclear Physics Consolidated Grant	David Ireland	Science and Technology Facilities Council (STFC)	ST/P004458/1	P&S - Physics & Astronomy