Direct neutrino-mass measurement with sub-electronvolt sensitivity

• Verfasst von: Aker, Max [VerfasserIn]
• Verfasst von: Rodejohann, Werner [VerfasserIn]
• Verfasst von: Spanier, Felix [VerfasserIn]
• Titel: Direct neutrino-mass measurement with sub-electronvolt sensitivity
• Körperschaft: KATRIN (Körperschaft) [VerfasserIn]
• Verf.angabe: the KATRIN collaboration
• E-Jahr: 2022
• Jahr: 14 February 2022
• Umfang: 7 S.
• Fussnoten: Das PDF enthält zusätzlich einen Anhang von 11 Seiten ; The KATRIN collaboration: M. Aker, F. Spanier, W. Rodejohann [und weitere 131 Verfasser] ; Gesehen am 23.03.2022
• Titel Quelle: Enthalten in: Nature physics
• Ort Quelle: Basingstoke : Nature Publishing Group, 2005
• Jahr Quelle: 2022
• Band/Heft Quelle: 18(2022), 2, Seite 160-166
• ISSN Quelle: 1745-2481
• DOI: doi:10.1038/s41567-021-01463-1
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Experimental nuclear physics
• Sach-SW: Experimental particle physics
• K10plus-PPN: 1796374334

Abstract

Since the discovery of neutrino oscillations, we know that neutrinos have non-zero mass. However, the absolute neutrino-mass scale remains unknown. Here we report the upper limits on effective electron anti-neutrino mass, mν, from the second physics run of the Karlsruhe Tritium Neutrino experiment. In this experiment, mν is probed via a high-precision measurement of the tritium β-decay spectrum close to its endpoint. This method is independent of any cosmological model and does not rely on assumptions whether the neutrino is a Dirac or Majorana particle. By increasing the source activity and reducing the background with respect to the first physics campaign, we reached a sensitivity on mν of 0.7 eV c-2 at a 90% confidence level (CL). The best fit to the spectral data yields $${{\mbox{}}}{m}_{\nu }^{2}{{\mbox{}}}$$ = (0.26 ± 0.34) eV2 c-4, resulting in an upper limit of mν < 0.9 eV c-2 at 90% CL. By combining this result with the first neutrino-mass campaign, we find an upper limit of mν < 0.8 eV c-2 at 90% CL.