Electroweak Measurements of Neutron Densities in CREX and PREX at JLab, USA

Journal Article · Sat Feb 01 00:00:00 EST 2014 · Eur.Phys.J. A

DOI:https://doi.org/10.1140/epja/i2014-14048-3· OSTI ID:1149582

Horowitz, Charles J. ^[1]; Kumar, Krishna S. ^[2]; Michaels, Robert W. ^[3]

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1. Indiana U.
2. UMass
3. JLAB

Measurement of the parity-violating electron scattering asymmetry is an established technique at Jefferson Lab and provides a new opportunity to measure the weak charge distribution and hence pin down the neutron radius in nuclei in a relatively clean and model-independent way. This is because the Z boson of the weak interaction couples primarily to neutrons. We will describe the PREX and CREX experiments on $${}^{208}$$Pb and $${}^{48}$$Ca respectively; these are both doubly-magic nuclei whose first excited state can be discriminated by the high resolution spectrometers at JLab. The heavier lead nucleus, with a neutron excess, provides an interpretation of the neutron skin thickness in terms of properties of bulk neutron matter. For the lighter $${}^{48}$$Ca nucleus, which is also rich in neutrons, microscopic nuclear theory calculations are feasible and are sensitive to poorly constrained 3-neutron forces.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1149582
• Report Number(s): JLAB-PHY-13-1809; DOE/OR/23177-2792; arXiv:1307.3572; FG02-88R40415- A018; FG02-87ER40365
• Journal Information: Eur.Phys.J. A, Vol. 50
• Country of Publication: United States
• Language: English