A new direct detection electron scattering experiment to search for the X17 particle

• DOI: 10.48550/arxiv.2301.08768
• Publication Date: 2023-01-01
• Authors: D. Dutta; H. Gao; A. Gasparian; T. J. Hague; N. Liyanage; R. Paremuzyan; C. Peng; W. Xiong; P. Achenbach; A. Ahmidouch; S. Ali; H. Avakian; C. Ayerbe-Gayoso; X. Bai; M. Battaglieri; H. Bhatt; A. Bianconi; J. Boyd; Danae Byer; P. L. Cole; G. Costantini; S. Davis; M. De Napoli; R. De Vita; B. Devkota; B. Dharmasena; J. Dunne; L. El Fassi; V. Gamage; L. Gan; K. Gnanvo; G. Gosta; D. Higinbotham; Colin Howell; S. Jeffas; Siyu Jian; A. Karki; B. Karki; V. Khachatryan; M. Khandaker; V. Kubarovsky; I. Larin; M. Leali; V. Mascagna; G. Matousek; S. Migliorati; R. Miskimen; P. Mohanmurthy; H. Nguyen; E. Pasyuk; A. Rathnayake; Jennifer Rittenho...; A. Shahinyan; A. Smith; S. Stepanyan; E. van Nieuwenhuizen; L. Venturelli; B. Yu; Z. Zhao; J. Zhou
• Keywords: Hidden sector; Tracking (education)

A new electron scattering experiment (E12-21-003) to verify and understand the nature of hidden sector particles, with particular emphasis on so-called X17 particle, has been approved at Jefferson Lab. The search for these particles is motivated by models introduced account a variety experimental observational puzzles: excess in $e^+e^-$ pairs observed multiple nuclear transitions, 4.2$\sigma$ disagreement between experiments standard model prediction muon anomalous magnetic moment, small-scale structure puzzle cosmological simulations. aforementioned particle hypothesized from $^8$Be M1, $^4$He M0, and, most recently, $^{12}$C E1 transitions their ground states ATOMKI group. This will use high resolution electromagnetic calorimeter or set limits production rate other $3 - 60$ MeV mass range via decay (or $\gamma\gamma$ limited tracking). In models, $1 100$ particularly well-motivated lower part this still remains unexplored. Our proposed direct detection magnetic-spectrometer-free setup (the PRad apparatus) detect all three final state visible an effective control background cover single setting. well-demonstrated allows essentially ready-to-run uniquely cost-effective sensitivity 8.9$\times$10$^{-8}$ 5.8$\times$10$^{-9}$ $\epsilon^2$, square kinetic mixing interaction constant sectors.