학술논문
A new direct detection electron scattering experiment to search for the X17 particle
Document Type
Working Paper
Author
Dutta, D.; Gao, H.; Gasparian, A.; Hague, T. J.; Liyanage, N.; Paremuzyan, R.; Peng, C.; Xiong, W.; Achenbach, P.; Ahmidouch, A.; Ali, S.; Avakian, H.; Ayerbe-Gayoso, C.; Bai, X.; Battaglieri, M.; Bhatt, H.; Bianconi, A.; Boyd, J.; Byer, D.; Cole, P. L.; Costantini, G.; Davis, S.; De Napoli, M.; De Vita, R.; Devkota, B.; Dharmasena, B.; Dunne, J.; Fassi, L. El; Gamage, V.; Gan, L.; Gnanvo, K.; Gosta, G.; Higinbotham, D.; Howell, C.; Jeffas, S.; Jian, S.; Karki, A.; Karki, B.; Khachatryan, V.; Khandaker, M.; Kubarovsky, V.; Larin, I.; Leali, M.; Mascagna, V.; Matousek, G.; Migliorati, S.; Miskimen, R.; Mohanmurthy, P.; Nguyen, H.; Pasyuk, E.; Rathnayake, A.; West, J. Rittenhouse; Shahinyan, A.; Smith, A.; Stepanyan, S.; van Nieuwenhuizen, E.; Venturelli, L.; Yu, B.; Zhao, Z.; Zhou, J.
Source
Subject
Language
Abstract
A new electron scattering experiment (E12-21-003) to verify and understand the nature of hidden sector particles, with particular emphasis on the so-called X17 particle, has been approved at Jefferson Lab. The search for these particles is motivated by new hidden sector models introduced to account for a variety of experimental and observational puzzles: excess in $e^+e^-$ pairs observed in multiple nuclear transitions, the 4.2$\sigma$ disagreement between experiments and the standard model prediction for the muon anomalous magnetic moment, and the small-scale structure puzzle in cosmological simulations. The aforementioned X17 particle has been hypothesized to account for the excess in $e^+e^-$ pairs observed from the $^8$Be M1, $^4$He M0, and, most recently, $^{12}$C E1 nuclear transitions to their ground states observed by the ATOMKI group. This experiment will use a high resolution electromagnetic calorimeter to search for or set new limits on the production rate of the X17 and other hidden sector particles in the $3 - 60$ MeV mass range via their $e^+e^-$ decay (or $\gamma\gamma$ decay with limited tracking). In these models, the $1 - 100$ MeV mass range is particularly well-motivated and the lower part of this range still remains unexplored. Our proposed direct detection experiment will use a magnetic-spectrometer-free setup (the PRad apparatus) to detect all three final state particles in the visible decay of a hidden sector particle for an effective control of the background and will cover the proposed mass range in a single setting. The use of the well-demonstrated PRad setup allows for an essentially ready-to-run and uniquely cost-effective search for hidden sector particles in the $3 - 60$ MeV mass range with a sensitivity of 8.9$\times$10$^{-8}$ - 5.8$\times$10$^{-9}$ to $\epsilon^2$, the square of the kinetic mixing interaction constant between hidden and visible sectors.
Comment: 6 pages, 7 figures. arXiv admin note: substantial text overlap with arXiv:2108.13276
Comment: 6 pages, 7 figures. arXiv admin note: substantial text overlap with arXiv:2108.13276