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Neutral and charged current deep inelastic ep scattering with longitudinally polarised lepton beams has been studied with the H1 and ZEUS detectors at HERA. The differential cross sections were measured in the range of four-momentum…

High Energy Physics - Experiment · Physics 2013-05-22 Aleksander Filip Zarnecki

The precise measurement of parity-violating asymmetries in parity-violating electron scattering experiments is a powerful tool for probing new physics beyond the Standard Model. Achieving the expected precision requires both experimental…

High Energy Physics - Phenomenology · Physics 2025-03-06 Elham Gorgannejad , Wouter Deconinck , David S. Armstrong

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

We report measurements of the parity-conserving beam-normal single-spin elastic scattering asymmetries $B_n$ on $^{12}$C and $^{27}$Al, obtained with an electron beam polarized transverse to its momentum direction. These measurements add an…

The impact of atomic parity violation experiments on determination of the weak mixing parameter $\sin^2 \theta$ and the Peskin-Takeuchi parameters $S$ and $T$ is reassessed in the light of recent electroweak measurements at LEP, SLAC, and…

High Energy Physics - Phenomenology · Physics 2016-08-24 Jonathan L. Rosner

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

The MOLLER experiment will measure the weak charge of the electron, $Q^e_W = 1 - 4\sin^2\theta_W$, with a precision of 2.3% by measuring the parity-violating asymmetry in electron-electron (M\oller) scattering. This measurement will provide…

High Energy Physics - Experiment · Physics 2019-08-17 Juliette Mammei

The physics case and an experimental overview of the MOLLER (Measurement Of a Lepton Lepton Electroweak Reaction) experiment at the 12 GeV upgraded Jefferson Lab are presented. A highlight of the Fundamental Symmetries subfield of the 2007…

Nuclear Experiment · Physics 2014-12-04 MOLLER Collaboration , J. Benesch , P. Brindza , R. D. Carlini , J-P. Chen , E. Chudakov , S. Covrig , M. M. Dalton , A. Deur , D. Gaskell , A. Gavalya , J. Gomez , D. W. Higinbotham , C. Keppel , D. Meekins , R. Michaels , B. Moffit , Y. Roblin , R. Suleiman , R. Wines , B. Wojtsekhowski , G. Cates , D. Crabb , D. Day , K. Gnanvo , D. Keller , N. Liyanage , V. V. Nelyubin , H. Nguyen , B. Norum , K. Paschke , V. Sulkosky , J. Zhang , X. Zheng , J. Birchall , P. Blunden , M. T. W. Gericke , W. R. Falk , L. Lee , J. Mammei , S. A. Page , W. T. H. van Oers , K. Dehmelt , A. Deshpande , N. Feege , T. K. Hemmick , K. S. Kumar , T. Kutz , R. Miskimen , M. J. Ramsey-Musolf , S. Riordan , N. Hirlinger Saylor , J. Bessuille , E. Ihloff , J. Kelsey , S. Kowalski , R. Silwal , G. De Cataldo , R. De Leo , D. Di Bari , L. Lagamba , E. NappiV. Bellini , F. Mammoliti , F. Noto , M. L. Sperduto , C. M. Sutera , P. Cole , T. A. Forest , M. Khandekar , D. McNulty , K. Aulenbacher , S. Baunack , F. Maas , V. Tioukine , R. Gilman , K. Myers , R. Ransome , A. Tadepalli , R. Beniniwattha , R. Holmes , P. Souder , D. S. Armstrong , T. D. Averett , W. Deconinck , W. Duvall , A. Lee , M. L. Pitt , J. A. Dunne , D. Dutta , L. El Fassi , F. De Persio , F. Meddi , G. M. Urciuoli , E. Cisbani , C. Fanelli , F. Garibaldi , K. Johnston , N. Simicevic , S. Wells , P. M. King , J. Roche , J. Arrington , P. E. Reimer , G. Franklin , B. Quinn , A. Ahmidouch , S. Danagoulian , O. Glamazdin , R. Pomatsalyuk , R. Mammei , J. W. Martin , T. Holmstrom , J. Erler , Yu. G. Kolomensky , J. Napolitano , K. A. Aniol , W. D. Ramsay , E. Korkmaz , D. T. Spayde , F. Benmokhtar , A. Del Dotto , R. Perrino , S. Barkanova , A. Aleksejevs , J. Singh

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…

In a global analysis of the latest parity-violating electron scattering measurements on nuclear targets, we demonstrate a significant improvement in the experimental knowledge of the weak neutral-current lepton-quark interactions at low…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. D. Young , R. D. Carlini , A. W. Thomas , J. Roche

Jefferson Lab experiment E08-007 measured the proton elastic form factor ratio $\mu_pG_E/G_M$ in the range of $Q^2=0.3-0.7(\mathrm{GeV}/c)^2$ by recoil polarimetry. Data were taken in 2008 at the Thomas Jefferson National Accelerator…

Nuclear Experiment · Physics 2011-08-25 Xiaohui Zhan

The GEp-III and GEp-2$\gamma$ experiments were carried out in Jefferson Lab's (JLab's) Hall C from 2007-2008, to extend the knowledge of $G_E^p/G_M^p$ to the highest practically achievable $Q^2$ and to search for effects beyond the Born…

Using the deep inelastic e^+p and e^-p charged and neutral current scattering cross sections previously published, a combined electroweak and QCD analysis is performed to determine electroweak parameters accounting for their correlation…

High Energy Physics - Experiment · Physics 2012-08-27 H1 Collaboration

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…

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…

Nuclear Experiment · Physics 2015-06-16 C. J. Horowitz , K. S. Kumar , R. Michaels

The high precision parity violating electron scattering experiments PREX and QWEAK are sensitive to radiative corrections. In this paper we introduce the PREX experiment that measures the neutron radius of $^{208}$Pb and discuss coulomb…

Nuclear Theory · Physics 2022-03-02 C. J. Horowitz

Parity-violating elastic electron-nucleon scattering at low momentum transfer allows one to access the nucleon's weak charge, the vector coupling of the $Z$-boson to the nucleon. In the Standard Model and at tree level, the weak charge of…

Nuclear Theory · Physics 2016-11-23 Mikhail Gorchtein , Hubert Spiesberger

Quasi-elastic scattering on $^{12}$C$(e,e'p)$ was measured in Hall C at Jefferson Lab for space-like 4-momentum transfer squared $Q^2$ in the range of 8--14.2\,(GeV/$c$)$^2$ with proton momenta up to 8.3\,GeV/$c$. The experiment was carried…

Low-energy neutral-current couplings arising in the Standard Model of electroweak interactions can be constrained in lepton scattering off hydrogen or a nuclear fixed target. Recent polarized electron scattering experiments at Jefferson Lab…

Nuclear Experiment · Physics 2023-01-11 Xiaochao Zheng , Jens Erler , Qishan Liu , Huber Spiesberger

To probe CP violation in the leptonic sector using GeV energy neutrino beams in current and future experiments using argon detectors, precise models of the complex underlying neutrino and antineutrino interactions are needed. The E12-14-012…