Measurement of the 3He spin-structure functions and of neutron (3He) spin-dependent sum rules at 0.035 ≤ Q2 ≤ 0.24 GeV2

Nucleon Polarizabilities and Compton Scattering as Playground for Chiral Perturbation Theory

“…A prominent example is the longitudinal-transverse polarizability of the proton (upper panel of Figure 4 and left panel of Figure 5), where the δ-and -expansion BχPT calculations are different by about a factor of 2. This "δ LT puzzle" could soon receive an experimental resolution, when the long-promised data from Jefferson Lab "Spin Physics Program" [102,129,135] on the proton spin structure function g 2 will be published [119]. Besides the polarizabilities, the Gerasimov-Drell-Hearn sum rule for the neutron will be verified by the E97-110 experiment using a helium-3 target [136].…”

“…In 1 , and polarized VVCS [45], related to δ LT , γ 0 , andγ 0 . The latter could be compared to new results from the Jefferson Lab "Spin Physics Program" for the proton spin structure functions g 1 and g 2 , see for instance the E08-027 experiment [102] and the E97-110 experiment [129]. Note that the HBχPT predictions for M (4) 1 and α L shown in Figures 11 and 13 were extracted from the VVCS amplitudes presented in Ref.…”

Nucleon Polarizabilities and Compton Scattering as a Playground for Chiral Perturbation Theory

“…In Figures 6, 8, 9, 10 and 11, one can see updated results from the recent O(p 4 /∆) BχPT prediction of unpolarized VVCS [28], related to α L and M (4) 1 , and polarized VVCS [29], related to δ LT , γ 0 and γ0 . The latter could be compared to new results from the Jefferson Lab "Spin Physics Program" for the proton spin structure functions g 1 and g 2 , see for instance the E08-027 experiment [100] and the E97-110 experiment [101].…”

Neutron spin structure from e-3He scattering with double spectator tagging at the electron-ion collider

“…While stable particles such as hydrogen are readily available for studies of the proton structure, the neutron, with its short half-life, cannot be used as a standalone fixed target for high luminosity scattering experiments. Instead, physicists have made use of deuterium and 3 He targets as effective neutron targets in order to extract unpolarized nucleon structure functions F 1 and F 2 [7,8] as well as polarized spin structure functions g 1 and g 2 [9,10].…”

“…Unfortunately, this same technique has never been done with fixed target polarized 3 He targets, where the low momentum recoil protons would need to pass through the glass of the target cell walls in order to be detected. Thus, to date, the neutron structure functions are extracted from 3 He measurements and require large model dependent corrections from the measured cross sections and asymmetries to extract the quantities of interest [10,13]. In Fig.…”