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arXiv · 1706.10160

A Radial Time Projection Chamber for $\alpha$ detection in CLAS at JLab

R. Dupré·S. Stepanyan·M. Hattawy·N. Baltzell·K. Hafidi·M. Battaglieri·S. Bueltmann·A. Celentano·R. De Vita·A. El Alaoui·L. El Fassi·H. Fenker·K. Kosheleva·S. Kuhn·P. Musico·S. Minutoli·M. Oliver·Y. Perrin·B. Torayev·E. Voutier
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Abstract

A new Radial Time Projection Chamber (RTPC) was developed at the Jefferson Laboratory to track low-energy nuclear recoils for the purpose of measuring exclusive nuclear reactions, such as coherent Deeply Virtual Compton Scattering and coherent meson production off $^4$He. In such processes, the $^4$He nucleus remains intact in the final state, however the CEBAF Large Acceptance Spectrometer (CLAS) cannot track the low energy $\alpha$ particles. In 2009, we carried out measurements using the CLAS spectrometer supplemented by the RTPC positioned directly around a gaseous $^4$He target, allowing a detection threshold as low as 12$\sim$MeV for $^4$He. This article discusses the design, principle of operation, calibration methods and the performances of this RTPC.

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R. Dupré, S. Stepanyan, M. Hattawy, N. Baltzell, K. Hafidi, M. Battaglieri, S. Bueltmann, A. Celentano, R. De Vita, A. El Alaoui, L. El Fassi, H. Fenker, K. Kosheleva, S. Kuhn, P. Musico, S. Minutoli, M. Oliver, Y. Perrin, B. Torayev, E. Voutier. 2017-06-30. A Radial Time Projection Chamber for $\alpha$ detection in CLAS at JLab. https://doi.org/10.1016/j.nima.2018.04.052

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