An upper limit on the

Barate, R.

doi:10.1007/s100520050149

Cited by 52 publications

(4 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The observation of neutrino oscillations demonstrated the existence of non-zero neutrino masses, allowing the π 0 → νν decay via Z-boson exchange. The direct experimental limit on the tau neutrino mass, m ντ < 18.2 MeV/c 2 at 95% confidence level (CL) [3], corresponds to a branching ratio (BR) for π 0 → νν below 5 × 10 −10 at 90% CL. A more stringent limit is set by cosmological constraints on the sum of the neutrino masses: Σm ν 1 eV/c 2 , implying BR(π 0 → νν) < 10 −24 , which is well below the current experimental sensitivity.…”

Section: Introductionmentioning

confidence: 99%

Search for π0 decays to invisible particles

Gil¹,

Kleimenova²,

Minucci³

et al. 2021

J. High Energ. Phys.

View full text Add to dashboard Cite

The NA62 experiment at the CERN SPS reports a study of a sample of 4 × 109 tagged π0 mesons from K+ → π+π0(γ), searching for the decay of the π0 to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of 4.4 × 10−9 is set on the branching ratio at 90% confidence level, improving on previous results by a factor of 60. This result can also be interpreted as a model- independent upper limit on the branching ratio for the decay K+ → π+X, where X is a particle escaping detection with mass in the range 0.110–0.155 GeV/c2 and rest lifetime greater than 100 ps. Model-dependent upper limits are obtained assuming X to be an axion-like particle with dominant fermion couplings or a dark scalar mixing with the Standard Model Higgs boson.

show abstract

Section: Introductionmentioning

confidence: 99%

Search for π0 decays to invisible particles

Gil¹,

Kleimenova²,

Minucci³

et al. 2021

J. High Energ. Phys.

View full text Add to dashboard Cite

show abstract

“…The upper limit for the mass of the lightest neutrino flavor v e was obtained from experiments for measurement of the high-energy part of the tritium βspectrum and recent experiments yield 2 eV upper limit (Weinheimer et al, 1999;Lobashev et al, 1999). As a result of the recent experiments, the upper mass limits of v µ and v τ were found to be 170 KeV (Assamagan et al, 1996) and 18.2 MeV (Barate et al, 1998), respectively. The Solar and atmospheric neutrino experiments allow to find the square mass differences 2 2 2 12 2 1 m m m ∆ = − and 2 2 2 23 3 2 m m m ∆ = − , but not the absolute values of the neutrino masses.…”

Section: Introductionmentioning

confidence: 99%

Estimations of Neutrino and Graviton Masses by a Phenomenological Mass Relation for Stable Particles

Valev¹

2015

Physics International

View full text Add to dashboard Cite

The ratio between the proton and electron masses was shown to be close to the ratio between the shortest lifetimes of particles, decaying by the electromagnetic and strong interactions. The inherent property of each fundamental interaction is defined, namely the Minimal Lifetime of the Interaction (MLTI). The rest mass of the Lightest Free Massive Stable Particle (LFMSP), acted upon by a particular interaction, is shown to be inversely proportional to MLTI. The found mass relation unifies the masses of four stable particles of completely different kinds (proton, electron, electron neutrino and graviton) and covers an extremely wide range of values, exceeding 40 orders of magnitude. On the basis of this mass relation, the electron neutrino and graviton masses have been approximately estimated to 6.5×10 −4 eV and ħH/c 2 ≈ 1.5×10 −33 eV, respectively. Besides, the last value has been obtained independently by dimensional analysis by means of three fundamental constants, namely the speed of light in vacuum (c), reduced Planck constant (ħ) and Hubble constant (H). The presence of an exceptionally small, yet nonzero mass of the graviton implies Yukawa potential of the gravitational field and a finite range of the gravity close to the Hubble distance cH −1. Therefore, the graviton mass determines a finite size of gravitationally connected (observable) universe for an arbitrary observer. It was shown that the rest energy of LFMSP, acted upon by a particular interaction, is close to Breit-Wigner's energy width of the shortest living state, decaying by the respective interaction.

show abstract

“…The most sensitive bounds on the mass of the ν τ can be derived from the analysis of the invariant-mass spectrum of semi-hadronic τ decays, e.g. the present best limit of m ν τ < 18.2 MeV=c 2 (95% confidence level) was based on the kinematics of 2939 (52) events of τ − → 2π − π þ ν τ (τ − → 3π − 2π þ ðπ − Þν τ ) [8]. This method depends on a determination of the kinematic end point of the mass spectrum; thus high precision on m τ is needed.…”

Section: Introductionmentioning

confidence: 99%

Precision measurement of the mass of theτlepton

Ablikim¹,

Ачасов

Ai³

et al. 2014

Phys. Rev. D

View full text Add to dashboard Cite

An energy scan near the τ pair production threshold has been performed using the BESIII detector. About 24 pb −1 of data, distributed over four scan points, were collected. This analysis is based on τ pair decays to ee, eμ, eh, μμ, μh, hh, eρ, μρ and πρ final states, where h denotes a charged π or K. The mass of the τ lepton is measured from a maximum likelihood fit to the τ pair production cross-section data to be m τ ¼ ð1776.91 AE 0.12 þ0.10 −0.13 Þ MeV=c 2 , which is currently the most precise value in a single measurement.

show abstract

An upper limit on the

Cited by 52 publications

References 11 publications

Search for π0 decays to invisible particles

Search for π0 decays to invisible particles

Estimations of Neutrino and Graviton Masses by a Phenomenological Mass Relation for Stable Particles

Precision measurement of the mass of theτlepton

Contact Info

Product

Resources

About