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Updated: Jan 6, 2026
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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
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Most Stringent Bound on Electron Neutrino Mass Obtained with a Scalable Low-Temperature Microcalorimeter Array
B K Alpert1, M Balata2, D T Becker3
1National Institute of Standards and Technology (NIST), Boulder, Colorado, USA.
Physical Review Letters
|October 19, 2025
Summary
Researchers set a new record for the most stringent upper bound on neutrino mass using electron capture decay measurements. The HOLMES experiment achieved a limit of less than 27 eV/c², advancing direct neutrino mass measurements.
Area of Science:
- Particle Physics
- Cosmology
- Nuclear Physics
Background:
- Determining the absolute neutrino mass scale is crucial for the Standard Model and cosmology.
- Direct kinematic measurements offer a model-independent approach to neutrino mass determination.
Purpose of the Study:
- To establish the most stringent upper bound on the effective electron neutrino mass.
- To validate the feasibility of ^{163}Ho calorimetry for future neutrino mass experiments.
Main Methods:
- Utilized the HOLMES experiment with ion-implanted transition-edge sensor (TES) microcalorimeters.
- Recorded 7×10⁷ electron capture decay events of ^{163}Ho over two months.
- Employed a Bayesian statistical analysis with high-resolution calorimetry (6 eV FWHM).
Main Results:
- Achieved the most stringent upper bound on the effective electron neutrino mass: m_β < 27 eV/c² at 90% credibility.
- Demonstrated the capability of TES microcalorimeters for precise calorimetric measurements.
Conclusions:
- The ^{163}Ho calorimetric technique is validated for next-generation neutrino mass experiments.
- Scalable TES-based microcalorimetry shows potential to significantly improve neutrino mass sensitivity.
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