The DarkLight Experiment: A Precision Search for New Physics at Low Energies

J. Balewski; J. Bernauer; J. Bessuille; R. Corliss; R. Cowan; C. Epstein; P. Fisher; D. Hasell; E. Ihloff; Y. Kahn; J. Kelsey; R. Milner; S. Steadman; J. Thaler; C. Tschalaer; C. Vidal; S. Benson; J. Boyce; D. Douglas; P. Evtushenko; C. Hernandez-Garcia; C. Keith; C. Tennant; S. Zhang; R. Alarcon; D. Blyth; R. Dipert; L. Ice; G. Randall; B. Dongwi; N. Kalantarians; M. Kohl; A. Liyanage; J. Nazeer; M. Garcon; R. Cervantes; K. Dehmelt; A. Deshpande; N. Feege; B. Surrow

arXiv · 1412.4717

The DarkLight Experiment: A Precision Search for New Physics at Low Energies

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Abstract

We describe the current status of the DarkLight experiment at Jefferson Laboratory. DarkLight is motivated by the possibility that a dark photon in the mass range 10 to 100 MeV/c$^2$ could couple the dark sector to the Standard Model. DarkLight will precisely measure electron proton scattering using the 100 MeV electron beam of intensity 5 mA at the Jefferson Laboratory energy recovering linac incident on a windowless gas target of molecular hydrogen. The complete final state including scattered electron, recoil proton, and e+e- pair will be detected. A phase-I experiment has been funded and is expected to take data in the next eighteen months. The complete phase-II experiment is under final design and could run within two years after phase-I is completed. The DarkLight experiment drives development of new technology for beam, target, and detector and provides a new means to carry out electron scattering experiments at low momentum transfers.

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J. Balewski, J. Bernauer, J. Bessuille, R. Corliss, R. Cowan, C. Epstein, P. Fisher, D. Hasell, E. Ihloff, Y. Kahn, J. Kelsey, R. Milner, S. Steadman, J. Thaler, C. Tschalaer, C. Vidal, S. Benson, J. Boyce, D. Douglas, P. Evtushenko, C. Hernandez-Garcia, C. Keith, C. Tennant, S. Zhang, R. Alarcon, D. Blyth, R. Dipert, L. Ice, G. Randall, B. Dongwi, N. Kalantarians, M. Kohl, A. Liyanage, J. Nazeer, M. Garcon, R. Cervantes, K. Dehmelt, A. Deshpande, N. Feege, B. Surrow. 2014-12-15. The DarkLight Experiment: A Precision Search for New Physics at Low Energies. https://arxiv.org/abs/1412.4717

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