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arXiv · 2203.08039

The Present and Future Status of Heavy Neutral Leptons

Asli M. Abdullahi·Pablo Barham Alzas·Brian Batell·Alexey Boyarsky·Saneli Carbajal·Animesh Chatterjee·Jose I. Crespo-Anadon·Frank F. Deppisch·Albert De Roeck·Marco Drewes·Alberto Martin Gago·Rebeca Gonzalez Suarez·Evgueni Goudzovski·Athanasios Hatzikoutelis·Marco Hufnagel·Philip Ilten·Alexander Izmaylov·Kevin J. Kelly·Juraj Klaric·Joachim Kopp·Suchita Kulkarni·Mathieu Lamoureux·Gaia Lanfranchi·Jacobo Lopez-Pavon·Oleksii Mikulenko·Michael Mooney·Miha Nemevsek·Maksym Ovchynnikov·Silvia Pascoli·Ryan Plestid·Mohamed Rashad Darwish·Federico Leo Redi·Oleg Ruchayskiy·Richard Ruiz·Mikhail Shaposhnikov·Ian M. Shoemaker·Robert Shrock·Alex Sousa·Nick Van Remortel·Vsevolod Syvolap·Volodymyr Takhistov·Jean-Loup Tastet·Inar Timiryasov·Aaron C. Vincent·Jaehoon Yu
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Abstract

The existence of non-zero neutrino masses points to the likely existence of multiple SM neutral fermions. When such states are heavy enough that they cannot be produced in oscillations, they are referred to as Heavy Neutral Leptons (HNLs). In this white paper we discuss the present experimental status of HNLs including colliders, beta decay, accelerators, as well as astrophysical and cosmological impacts. We discuss the importance of continuing to search for HNLs, and its potential impact on our understanding on key fundamental questions, and additionally we outline the future prospects for next-generation future experiments or upcoming accelerator run scenarios.

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Asli M. Abdullahi, Pablo Barham Alzas, Brian Batell, Alexey Boyarsky, Saneli Carbajal, Animesh Chatterjee, Jose I. Crespo-Anadon, Frank F. Deppisch, Albert De Roeck, Marco Drewes, Alberto Martin Gago, Rebeca Gonzalez Suarez, Evgueni Goudzovski, Athanasios Hatzikoutelis, Marco Hufnagel, Philip Ilten, Alexander Izmaylov, Kevin J. Kelly, Juraj Klaric, Joachim Kopp, Suchita Kulkarni, Mathieu Lamoureux, Gaia Lanfranchi, Jacobo Lopez-Pavon, Oleksii Mikulenko, Michael Mooney, Miha Nemevsek, Maksym Ovchynnikov, Silvia Pascoli, Ryan Plestid, Mohamed Rashad Darwish, Federico Leo Redi, Oleg Ruchayskiy, Richard Ruiz, Mikhail Shaposhnikov, Ian M. Shoemaker, Robert Shrock, Alex Sousa, Nick Van Remortel, Vsevolod Syvolap, Volodymyr Takhistov, Jean-Loup Tastet, Inar Timiryasov, Aaron C. Vincent, Jaehoon Yu. 2022-03-15. The Present and Future Status of Heavy Neutral Leptons. https://doi.org/10.1088/1361-6471/ac98f9

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