title: Measurement of Compton scattering from the deuteron and an improved extraction of the neutron electromagnetic polarizabilities.
abstract: The electromagnetic polarizabilities of the nucleon are fundamental properties that describe its response to external electric and magnetic fields. They can be extracted from Compton-scattering data-and have been, with good accuracy, in the case of the proton. In contradistinction, information for the neutron requires the use of Compton scattering from nuclear targets. Here, we report a new measurement of elastic photon scattering from deuterium using quasimonoenergetic tagged photons at the MAX IV Laboratory in Lund, Sweden. These first new data in more than a decade effectively double the world data set. Their energy range overlaps with previous experiments and extends it by 20 MeV to higher energies. An analysis using chiral effective field theory with dynamical Δ(1232) degrees of freedom shows the data are consistent with and within the world data set. After demonstrating that the fit is consistent with the Baldin sum rule, extracting values for the isoscalar nucleon polarizabilities, and combining them with a recent result for the proton, we obtain the neutron polarizabilities as αn=[11.55±1.25(stat)±0.2(BSR)±0.8(th)]×10(-4)  fm(3) and βn=[3.65∓1.25(stat)±0.2(BSR)∓0.8(th)]×10(-4)  fm(3), with χ(2)=45.2 for 44 degrees of freedom.
authors.affiliation: Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: L S
authors.initials: LS
authors.lastname: Myers
authors.affiliation: School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom.
authors.forename: J R M
authors.initials: JR
authors.lastname: Annand
authors.affiliation: MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Brudvik
authors.affiliation: Institute for Nuclear Studies, Department of Physics, The George Washington University, Washington, DC 20052, USA.
authors.forename: G
authors.initials: G
authors.lastname: Feldman
authors.affiliation: Department of Physics, Lund University, SE-221 00 Lund, Sweden.
authors.forename: K G
authors.initials: KG
authors.lastname: Fissum
authors.affiliation: Institute for Nuclear Studies, Department of Physics, The George Washington University, Washington, DC 20052, USA.
authors.forename: H W
authors.initials: HW
authors.lastname: Grießhammer
authors.affiliation: MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Hansen
authors.affiliation: Department of Physics, Duke University, Durham, North Carolina 27708, USA.
authors.forename: S S
authors.initials: SS
authors.lastname: Henshaw
authors.affiliation: MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Isaksson
authors.affiliation: School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom.
authors.forename: R
authors.initials: R
authors.lastname: Jebali
authors.affiliation: Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Kovash
authors.affiliation: MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Lundin
authors.affiliation: School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom.
authors.forename: J A
authors.initials: JA
authors.lastname: McGovern
authors.affiliation: Kepler Centre for Astro- and Particle Physics, Physikalisches Institut, Universität Tübingen, D-72076 Tübingen, Germany.
authors.forename: D G
authors.initials: DG
authors.lastname: Middleton
authors.affiliation: Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Nathan
authors.affiliation: Department of Physics and Astronomy and Institute of Nuclear and Particle Physics, Ohio University, Athens, Ohio 45701, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Phillips
authors.affiliation: MAX IV Laboratory, Lund University, SE-221 00 Lund, Sweden and Department of Physics, Lund University, SE-221 00 Lund, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Schröder
authors.affiliation: Department of Physics, Duke University, Durham, North Carolina 27708, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Stave