English
Related papers

Related papers: The Qweak High Performance LH2 Target

200 papers

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…

The g2p/GEp experiments used a solid NH3 polarized target, where the polarization of the target is sensitive to temperature and radiation. The beam current was limited to 5-100 nA during the experiment to avoid too much depolarization of…

Instrumentation and Detectors · Physics 2016-06-28 Pengjia Zhu

The GEp-III and GEp-2$\gamma$ experiments, carried out in Jefferson Lab's Hall C from 2007-2008, consisted of measurements of polarization transfer in elastic electron-proton scattering at momentum transfers of $Q^2 = 2.5, 5.2, 6.8,$ and…

We present an overview of the electroweak physics program of the SLD experiment at the Stanford Linear Accelerator Center (SLAC). A data sample of 550K Z0 decays has been collected. This experiment utilizes a highly polarized electron beam,…

High Energy Physics - Experiment · Physics 2007-05-23 M. Woods

The physics program in Hall A at Jefferson Lab commenced in the summer of 1997 with a detailed investigation of the 16O(e,e'p) reaction in quasielastic, constant (q,w) kinematics at Q^2 ~ 0.8 (GeV/c)^2, q ~ 1 GeV/c, and w ~ 445 MeV. Use of…

Nuclear Experiment · Physics 2008-11-26 K. G. Fissum

The P2 experiment aims at high-precision measurements of the parity-violating asymmetry in elastic electron-proton and electron-$^{12}$C scatterings with longitudinally polarized electrons. We discuss here the sensitivity of P2 to…

High Energy Physics - Phenomenology · Physics 2022-05-23 Ingolf Bischer , P. S. Bhupal Dev , Werner Rodejohann , Xun-Jie Xu , Yongchao Zhang

We report the most precise measurement to date of a parity-violating asymmetry in elastic electron-proton scattering. The measurement was carried out with a beam energy of 3.03 GeV and a scattering angle <theta_lab>=6 degrees, with the…

Nuclear Experiment · Physics 2012-08-27 The HAPPEX Collaboration

We study the possibility to measure sin^2 theta_W by neutrino-electron scattering at a value of the momentum transfer Q ~ 30 MeV with a precision of 0.24% which is only a factor three below the one obtained by LEP-I at the Z-pole. The…

High Energy Physics - Phenomenology · Physics 2011-08-29 Sanjib Kumar Agarwalla , Patrick Huber

Systematic studies on metastability exchange optical pumping of $^3$He nuclei have been performed at Jefferson Lab using a 1-torr sealed cell at magnetic fields from 2 to 4 T. The effects of the discharge intensity, pump laser power, and…

Instrumentation and Detectors · Physics 2024-03-01 X. Li , J. D. Maxwell , D. Nguyen , J. Brock , C. D. Keith , R. G. Milner , X. Wei

The E12-14-012 experiment, performed in Jefferson Lab Hall A, has collected exclusive electron-scattering data (e,e$^\prime$p) in parallel kinematics using natural argon and natural titanium targets. Here, we report the first results of the…

The stopping power of antiprotons in atomic and molecular hydrogen as well as helium was calculated in an impact-energy range from 1 keV to 6.4 MeV. In the case of H2 and He the targets were described with a single-active electron model…

Atomic Physics · Physics 2015-05-13 Armin Lühr , Alejandro Saenz

We demonstrated a 967 nm diode end-pumped Er:GSGG laser operated at 2.794 Micrometer with spectrum width 3.6 nm in the continuous wave(CW) mode. The maximum output power of 440 mW is obtained at an incident pumping power of 3.4 W, which…

Optics · Physics 2015-06-12 Z. H. Wu , D. L. Sun , S. Z. Wang , J. Q. Luo , X. L. Li , L. Huang , A. L. Hu , Y. Q. Tang , Q. Guo

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from the proton. The kinematic point (theta_lab = 12.3 degrees and Q^2=0.48 (GeV/c)^2) is chosen to provide sensitivity, at a level…

Nuclear Experiment · Physics 2010-05-27 HAPPEX Collaboration , K. A. Aniol

The Large Hadron-Electron Collider (LHeC) will operate at $\sqrt{s}$ = 1.2 TeV and accumulate about 1/ab of integrated electron-proton luminosity. Novel studies of high energy photon-photon interactions at the LHeC, at the $\gamma\gamma$…

High Energy Physics - Experiment · Physics 2021-09-24 Krzysztof Piotrzkowski , Yuji Yamazaki

The cross section of atomic electron Compton scattering $\gamma + e \rightarrow \gamma^\prime + e^\prime $ was measured in the 4.40--5.475 GeV photon beam energy region by the {\em PrimEx} collaboration at Jefferson Lab with an accuracy of…

A lead-glass hodoscope calorimeter that was constructed for use in the Jefferson Lab Real Compton Scattering experiment is described. The detector provides a measurement of the coordinates and the energy of scattered photons in the GeV…

Measurement of the parity-violating electron scattering asymmetry from ${}^{208}$Pb has demonstrated a new opportunity at Jefferson Lab to measure the weak charge distribution and hence pin down the neutron radius in nuclei in a relatively…

Nuclear Experiment · Physics 2015-10-21 Robert Michaels

Using an affordable ytterbium laser with sub-mJ of energy combined with a novel pulse compression technique, we demonstrate an extremely competitive state-of-the-art terahertz (THz) source with 53 mW of average power and 310 kV/cm at focus…

Optics · Physics 2022-05-25 L. Guiramand , J. E. Nkeck , X. Ropagnol , T. Ozaki , F. Blanchard

A multi-cell He gas-scintillator active target, designed for the measurement of photoreaction cross sections, is described. The target has four main chambers, giving an overall thickness of 0.103 $\mathrm{g/cm^{2}}$ at an operating pressure…

We present an experimental apparatus to control and visualize the response of a liquid target to a laser-induced vaporization. We use a millimeter-sized drop as target and present two liquid-dye solutions that allow a variation of the…

Instrumentation and Detectors · Physics 2017-09-11 Alexander L. Klein , Detlef Lohse , Michel Versluis , Hanneke Gelderblom