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arXiv · 2303.14185

First Direct Observation of Collider Neutrinos with FASER at the LHC

FASER Collaboration·Henso Abreu·John Anders·Claire Antel·Akitaka Ariga·Tomoko Ariga·Jeremy Atkinson·Florian U. Bernlochner·Tobias Blesgen·Tobias Boeckh·Jamie Boyd·Lydia Brenner·Franck Cadoux·David W. Casper·Charlotte Cavanagh·Xin Chen·Andrea Coccaro·Ansh Desai·Sergey Dmitrievsky·Monica D'Onofrio·Yannick Favre·Deion Fellers·Jonathan L. Feng·Carlo Alberto Fenoglio·Didier Ferrere·Stephen Gibson·Sergio Gonzalez-Sevilla·Yuri Gornushkin·Carl Gwilliam·Daiki Hayakawa·Shih-Chieh Hsu·Zhen Hu·Giuseppe Iacobucci·Tomohiro Inada·Sune Jakobsen·Hans Joos·Enrique Kajomovitz·Hiroaki Kawahara·Alex Keyken·Felix Kling·Daniela Köck·Umut Kose·Rafaella Kotitsa·Susanne Kuehn·Helena Lefebvre·Lorne Levinson·Ke Li·Jinfeng Liu·Jack MacDonald·Chiara Magliocca·Fulvio Martinelli·Josh McFayden·Matteo Milanesio·Dimitar Mladenov·Théo Moretti·Magdalena Munker·Mitsuhiro Nakamura·Toshiyuki Nakano·Marzio Nessi·Friedemann Neuhaus·Laurie Nevay·Hidetoshi Otono·Hao Pang·Lorenzo Paolozzi·Brian Petersen·Francesco Pietropaolo·Markus Prim·Michaela Queitsch-Maitland·Filippo Resnati·Hiroki Rokujo·Elisa Ruiz-Choliz·Jorge Sabater-Iglesias·Osamu Sato·Paola Scampoli·Kristof Schmieden·Matthias Schott·Anna Sfyrla·Savannah Shively·Yosuke Takubo·Noshin Tarannum·Ondrej Theiner·Eric Torrence·Serhan Tufanli·Svetlana Vasina·Benedikt Vormwald·Di Wang·Eli Welch·Stefano Zambito
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Abstract

We report the first direct observation of neutrino interactions at a particle collider experiment. Neutrino candidate events are identified in a 13.6 TeV center-of-mass energy $pp$ collision data set of 35.4 fb${}^{-1}$ using the active electronic components of the FASER detector at the Large Hadron Collider. The candidates are required to have a track propagating through the entire length of the FASER detector and be consistent with a muon neutrino charged-current interaction. We infer $153^{+12}_{-13}$ neutrino interactions with a significance of 16 standard deviations above the background-only hypothesis. These events are consistent with the characteristics expected from neutrino interactions in terms of secondary particle production and spatial distribution, and they imply the observation of both neutrinos and anti-neutrinos with an incident neutrino energy of significantly above 200 GeV.

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FASER Collaboration, Henso Abreu, John Anders, Claire Antel, Akitaka Ariga, Tomoko Ariga, Jeremy Atkinson, Florian U. Bernlochner, Tobias Blesgen, Tobias Boeckh, Jamie Boyd, Lydia Brenner, Franck Cadoux, David W. Casper, Charlotte Cavanagh, Xin Chen, Andrea Coccaro, Ansh Desai, Sergey Dmitrievsky, Monica D'Onofrio, Yannick Favre, Deion Fellers, Jonathan L. Feng, Carlo Alberto Fenoglio, Didier Ferrere, Stephen Gibson, Sergio Gonzalez-Sevilla, Yuri Gornushkin, Carl Gwilliam, Daiki Hayakawa, Shih-Chieh Hsu, Zhen Hu, Giuseppe Iacobucci, Tomohiro Inada, Sune Jakobsen, Hans Joos, Enrique Kajomovitz, Hiroaki Kawahara, Alex Keyken, Felix Kling, Daniela Köck, Umut Kose, Rafaella Kotitsa, Susanne Kuehn, Helena Lefebvre, Lorne Levinson, Ke Li, Jinfeng Liu, Jack MacDonald, Chiara Magliocca, Fulvio Martinelli, Josh McFayden, Matteo Milanesio, Dimitar Mladenov, Théo Moretti, Magdalena Munker, Mitsuhiro Nakamura, Toshiyuki Nakano, Marzio Nessi, Friedemann Neuhaus, Laurie Nevay, Hidetoshi Otono, Hao Pang, Lorenzo Paolozzi, Brian Petersen, Francesco Pietropaolo, Markus Prim, Michaela Queitsch-Maitland, Filippo Resnati, Hiroki Rokujo, Elisa Ruiz-Choliz, Jorge Sabater-Iglesias, Osamu Sato, Paola Scampoli, Kristof Schmieden, Matthias Schott, Anna Sfyrla, Savannah Shively, Yosuke Takubo, Noshin Tarannum, Ondrej Theiner, Eric Torrence, Serhan Tufanli, Svetlana Vasina, Benedikt Vormwald, Di Wang, Eli Welch, Stefano Zambito. 2023-03-24. First Direct Observation of Collider Neutrinos with FASER at the LHC. https://doi.org/10.1103/physrevlett.131.031801

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