A White Paper on SoLID (Solenoidal Large Intensity Device)

TL;DR

The paper proposes the SoLID spectrometer for Jefferson Lab, highlighting its large acceptance and high luminosity to enable advanced studies in nucleon structure, Standard Model tests, and non-perturbative QCD phenomena.

Contribution

It introduces the design and physics goals of the new SoLID device, emphasizing its unique capabilities and approved experiments for exploring nucleon structure and fundamental interactions.

Findings

SoLID enables precision measurements in semi-inclusive DIS.

It allows detailed studies of nucleon spin and momentum distributions.

The device is approved for multiple high-impact experiments.

Abstract

In order to fully exploit the physics potential of Jefferson Lab after 12 GeV energy upgrade, a new Solenoidal Large Acceptance Device (SoLID) is proposed. The SoLID spectrometer, with its unique capability of large acceptance and high luminosity, is ideal for precision measurements in semi-inclusive DIS to study transverse spin and transverse-momentum-dependent parton distributions of the nucleon, and for parity-violating Deep Inelastic Scattering (DIS) to perform precision tests of the Standard Model at low energy as well as addressing specific issues in nucleon structure including charge symmetry violation, d/u ratio and higher-twist effects due to di-quark. SoLID is also essential for precision measurements of J/\psi electroproduction in the threshold region to study non-perturbative gluon dynamics and interaction. Five highly rated SoLID experiments and two "run group" experiments have been approved by the JLab Physics Advisory Committee. The physics program is presented along with an overview of the SoLID instrumentation and its current status.