Related papers: Redesigning the Jefferson Lab Hall A Beam Line for…
A new precision measurement of the parity violating analyzing power in longitudinally polarized electron scattering from the proton at very low Q^2 at an incident energy of 1.16 GeV is in the final stages of preparation for execution at…
Characterization of the minute cosmic microwave background polarization signature requires multi-frequency, high-throughput precision instrument systems. We have previously described the detector fabrication of a 40 GHz focal plane and now…
Constancy and anisotropy of vacuum refractive index serves as a strong way to probe the predictions of theories beyond the standard model (BSM), especially those that predict breaking of local Lorentz and CPT symmetries. For photons of…
We report a high precision measurement of electron beam polarization using Compton polarimetry. The measurement was made in experimental Hall A at Jefferson Lab during the CREX experiment in 2020. A total uncertainty of dP/P=0.36% was…
Meson photoproduction is an important tool in the study of baryon resonances. The spectrum of broad and overlapping nucleon excitations can be greatly clarified by use of polarization observables. The N* program at Jefferson Lab with the…
As compared to electron storage rings, one advantage of recirculating linear accelerators is that the beam properties at target are no longer dominated by the equilibrium between quantum radiative diffusion and radiation damping because new…
Polarimetry with permille-level precision is essential for future electron-positron linear colliders. Compton polarimeters can reach negligible statistical uncertainties within seconds of measurement time. The dominating systematic…
In our previous studies on the development of a new type of matching section for dielectric-loaded accelerating (DLA) structures, a significant discrepancy was found between measurements and simulations [Y. Wei, et al., Phys. Rev. Accel.…
Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental program at the next generation of lepton accelerators. In the context of the Hadronic Physics program at the Jefferson Laboratory…
APEX is an experiment at Thomas Jefferson National Accelerator Facility (JLab) in Virginia, USA, that searches for a new gauge boson ($A^\prime$) with sub-GeV mass and coupling to ordinary matter of $g^\prime \sim (10^{-6} - 10^{-2}) e$.…
A cylindrical GEM tracker is under construction in order to replace and improve the inner tracking system of the BESIII experiment. Tests with planar chamber prototypes were carried out on the H4 beam line of SPS (CERN) with muons of 150…
We report on the highest precision yet achieved in the measurement of the polarization of a low energy, $\mathcal{O}$(1 GeV), electron beam, accomplished using a new polarimeter based on electron-photon scattering, in Hall~C at Jefferson…
Since May 1999 the BABAR detector has been taking data at the PEP-II asymmetric electron-positron collider at the Stanford Linear Accelerator Center, California. This experiment requires a very large data sample and the PEP-II accelerator…
A new Compton longitudinal polarimeter currently under construction for HERA is presented. The key component of the polarimeter is a Fabry-Perot cavity located around the electron beam pipe. With such an optical cavity, a continuous laser…
A new tagged photon beam facility is being constructed in experimental Hall-D at Jefferson Lab as a part of the 12 GeV upgrade program. The 9 GeV linearly-polarized photon beam will be produced via coherent Bremsstrahlung using the CEBAF…
The ALPHA Collaboration, based at the CERN Antiproton Decelerator, has recently implemented a novel beamline for low-energy ($\lesssim$ 100 eV) positron and antiproton transport between cylindrical Penning traps that have strong axial…
We present a preliminary analysis of the photon beam asymmetry observable (Sigma) from the photoproduction reaction channel gamma+ n -> p + pi-. This new data was obtained using the near-4pi CEBAF Large Acceptance Spectrometer (CLAS) at…
A subset of results from the recently completed Jefferson Lab Qweak experiment are reported. This experiment, sensitive to physics beyond the Standard Model, exploits the small parity-violating asymmetry in elastic ep scattering to provide…
Many advanced techniques have been developed, tested and implemented in the last decades in almost all circular accelerators across the world to measure the linear optics. However, the greater availability and accuracy of beam diagnostics…
A new electromagnetic calorimeter (ECAL) consisting of 1596 lead tungstate PbWO$_{\rm 4}$ scintillating crystals has been fabricated and installed in the experimental Hall D at Jefferson Lab (JLab). The high-granularity, high-resolution…