德国慕尼黑工业大学Christoph Wiesinger团队实现了基于259天KATRIN数据的直接中微子质量测量。2025年4月11日，《科学》杂志发表了这一成果。
中微子具有非衰减的静止质量，这证明了物理学超越了基本粒子的标准模型。它们的绝对质量在从粒子物理学到宇宙学的各个领域都具有相关性。
研究组报道了用KATRIN实验寻找有效电子反中微子质量的情况。KATRIN对接近运动学终点的氚β衰变进行精确光谱分析。在前五个测量活动的基础上，得出了m2v=-0.14 +0.13 -0.15 eV2的最佳拟合值，导致在90%置信水平下mν<0.45 eV的上限。由于在259个测量日内收集了3600万个电子，背景水平大幅降低，系统不确定性得到改善，这一结果使KATRIN之前的界限收紧了近两倍。
附：英文原文
Title: Direct neutrino-mass measurement based on 259 days of KATRIN data
Author: KATRIN Collaboration, Max Aker, Dominic Batzler, Armen Beglarian, Jan Behrens, Justus Beisenktter, Matteo Biassoni, Benedikt Bieringer, Yanina Biondi, Fabian Block, Steffen Bobien, Matthias Bttcher, Beate Bornschein, Lutz Bornschein, Tom S. Caldwell, Marco Carminati, Auttakit Chatrabhuti, Suren Chilingaryan, Byron A. Daniel, Karol Debowski, Martin Descher, Deseada Díaz Barrero, Peter J. Doe, Otokar Dragoun, Guido Drexlin, Frank Edzards, Klaus Eitel, Enrico Ellinger, Ralph Engel, Sanshiro Enomoto, Arne Felden, Caroline Fengler, Carlo Fiorini, Joseph A. Formaggio, Christian Forstner, Florian M. Frnkle, Kevin Gauda, Andrew S. Gavin, Woosik Gil, Ferenc Glück, Steffen Grohmann, Robin Grssle, Rainer Gumbsheimer, Nathanael Gutknecht, Volker Hannen, Leonard Hasselmann, Norman Haumann, Klaus Helbing, Hanna Henke, Svenja Heyns, Stephanie Hickford, Roman Hiller, David Hillesheimer, Dominic Hinz, Thomas Hhn, Anton Huber, Alexander Jansen, Christian Karl, Jonas Kellerer, Khanchai Khosonthongkee, Matthias Kleifges, Manuel Klein, Joshua Kohpei, Christoph Khler, Leonard Kllenberger, Andreas Kopmann, Neven Kova, Alojz Kovalík, Holger Krause, Luisa La Cascio, Thierry Lasserre, Joscha Lauer, Thanh-Long Le, Ondej Lebeda, Bjoern Lehnert, Gen Li, Alexey Lokhov, Moritz Machatschek, Martin Mark, Alexander Marsteller, Eric L. Martin, Christin Melzer, Susanne Mertens, Shailaja Mohanty, Jalal Mostafa, Klaus Müller, Andrea Nava, Holger Neumann, Simon Niemes, Anthony Onillon, Diana S. Parno, Maura Pavan, Udomsilp Pinsook, Alan W. P. Poon, Jose Manuel Lopez Poyato, Stefano Pozzi, Florian Priester, Jan Ráli, Shivani Ramachandran, R. G. Hamish Robertson, Caroline Rodenbeck, Marco Rllig, Carsten Rttele, Milos Ryavy, Rudolf Sack, Alejandro Saenz, Richard Salomon, Peter Schfer, Magnus Schlsser, Klaus Schlsser, Lisa Schlüter, Sonja Schneidewind, Ulrich Schnurr, Michael Schrank, Jannis Schürmann, Ann-Kathrin Schütz, Alessandro Schwemmer, Adrian Schwenck, Michal efík, Daniel Siegmann, Frank Simon, Felix Spanier, Daniela Spreng, Warintorn Sreethawong, Markus Steidl, Jaroslav torek, Xaver Stribl, Michael Sturm, Narumon Suwonjandee, Nicholas Tan Jerome, Helmut H. Telle, Larisa A. Thorne, Thomas Thümmler, Simon Tirolf, Nikita Titov, Igor Tkachev, Korbinian Urban, Kathrin Valerius, Drahoslav Vénos, Christian Weinheimer, Stefan Welte, Jürgen Wendel, Christoph Wiesinger, John F. Wilkerson, Joachim Wolf, Sascha Wüstling, Johanna Wydra, Weiran Xu, Sergey Zadorozhny, Genrich Zeller
Issue&Volume: 2025-04-11
Abstract: That neutrinos carry a nonvanishing rest mass is evidence of physics beyond the Standard Model of elementary particles. Their absolute mass holds relevance in fields from particle physics to cosmology. We report on the search for the effective electron antineutrino mass with the KATRIN experiment. KATRIN performs precision spectroscopy of the tritium β-decay close to the kinematic endpoint. On the basis of the first five measurement campaigns, we derived a best-fit value of m2v=-0.14 +0.13 -0.15 eV2, resulting in an upper limit of mν < 0.45 eV at 90% confidence level. Stemming from 36 million electrons collected in 259 measurement days, a substantial reduction of the background level, and improved systematic uncertainties, this result tightens KATRIN’s previous bound by a factor of almost two.
DOI: adq9592
Source: https://www.science.org/doi/10.1126/science.adq9592