Schematic representation of the setup of the KATRIN experiment. Credit: Leonard Köllenberger for the KATRIN partnership
Comprehensive Data Analysis: First Push into the Range below 1 eV
Thorough analysis of these data represented a huge challenge for the worldwide group led by the two planners Dr. Magnus Schlösser, KIT, and Professor Susanne Mertens, Max Planck Institute for Physics and Technical University of Munich: Each and every result on the neutrino mass, no matter how small, had actually to be investigated in information. “This elaborate and laborious work was the only way to leave out an organized predisposition of our result due to misshaping procedures. We are especially pleased with our analysis team that accepted this substantial difficulty with fantastic dedication and succeeded,” Schlösser and Mertens state. The speculative data from the first year of measurements and modeling based upon a vanishingly little neutrino mass matched completely: It enabled them to determine a new ceiling of 0.8 eV for the neutrino mass, the researchers explain. This is the very first time that a direct neutrino mass experiment has gone into the sub-eV mass range that is of high relevance to cosmology and particle physics, as it is here where the fundamental mass scale of neutrinos is assumed to lie. “The particle physics neighborhood is delighted that the 1-eV barrier has actually been broken by KATRIN,” remarks neutrino professional John Wilkerson, University of North Carolina, who chairs the KATRIN Executive Board.
” The success was based decisively on the reality that the ramp-up of the source to nominal source strengths at the Karlsruhe Tritium Laboratory and the operation of the cryoinfrastructure, spectrometer, and detector went smoothly. This was because of the expert commitment of our extremely motivated personnel which supported this massive experiment,” Schlösser emphasizes.
Further Measurements to Improve Sensitivity
The researchers included in the KATRIN project describe their next objectives: “Further measurements of the neutrino mass will continue up until the end of 2024. From 2025, it will enable KATRIN to embark on a search for “sterilized” neutrinos with masses in the keV variety.
For more on this research study, see New World Record: “Ghost Particle” Experiment Limits Neutrino Mass With Unprecedented Precision.
Referral: “Direct neutrino-mass measurement with sub-eV level of sensitivity” by The KATRIN Collaboration, 14 February 2022, Nature Physics.DOI: 10.1038/ s41567-021-01463-1.
View into the primary spectrometer of the KATRIN experiment to figure out the mass of the neutrino on Campus North of KIT Credit: Markus Breig, KIT.
Brand-new world record: Neutrinos are lighter than 0.8 electron volts.
Neutrinos are perhaps the most remarkable primary particles in our universe. In cosmology they play an important function in the formation of large-scale structures, while in particle physics their very small mass sets them apart, indicating brand-new physics phenomena beyond our existing theories. Without a measurement of the mass of neutrinos, our understanding of the universe will stay incomplete.
This is the difficulty taken by the global KArlsruhe TRItium Neutrino (KATRIN) experiment at KIT as the worlds most delicate scale for neutrinos. Partners from six nations are included. KATRIN uses the beta decay of tritium, an unstable hydrogen isotope, to identify the mass of the neutrino by means of the energy distribution of electrons released in the decay process. This requires a major technological effort: The 70 m long experiment homes the world ´ s most intense tritium source in addition to a giant spectrometer to measure the energies of decay electrons with unmatched accuracy. After starting clinical measurements in 2019, the high quality of the data has been continually improved over the last 2 years. “KATRIN as an explore the highest technological requirements is now running like an ideal clockwork,” states Professor Guido Drexlin from KIT, the job leader and one of the two co-spokespersons of the experiment. Teacher Christian Weinheimer, University of Münster, the other co-spokesperson, adds: “Reduction of the background rate and increase in the signal rate were decisive for the new outcome.”
KATRIN utilizes the beta decay of tritium, an unstable hydrogen isotope, to figure out the mass of the neutrino by means of the energy distribution of electrons launched in the decay procedure. The experimental data from the very first year of measurements and modeling based on a vanishingly little neutrino mass matched perfectly: It allowed them to determine a brand-new upper limitation of 0.8 eV for the neutrino mass, the researchers point out. This is the very first time that a direct neutrino mass experiment has actually gone into the sub-eV mass range that is of high relevance to cosmology and particle physics, as it is here where the essential mass scale of neutrinos is assumed to lie. The scientists included in the KATRIN task explain their next objectives: “Further measurements of the neutrino mass will continue till the end of 2024. From 2025, it will permit KATRIN to embark on a search for “sterile” neutrinos with masses in the keV variety.
