Tritium beta decay with additional emission of new light bosons

Arcadi, Giorgio; Heeck, Julian; Heizmann, F.; Mertens, S.; Queiroz, Farinaldo S.; Rodejohann, Werner; Slezák, M.; Valerius, K.

doi:10.1007/jhep01(2019)206

Cited by 27 publications

(19 citation statements)

References 94 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In other models of neutrino interaction, the structure of the coupling matrix could be more arbitrary. In all cases though, g ij is subject to important flavor-dependent bounds [103][104][105] arising from meson, tritium, and gauge boson decay kinematics.…”

Section: Neutrino Interaction Modelmentioning

confidence: 99%

Neutrino puzzle: Anomalies, interactions, and cosmological tensions

2020

View full text Add to dashboard Cite

New physics in the neutrino sector might be necessary to address anomalies between different neutrino oscillation experiments. Intriguingly, it also offers a possible solution to the discrepant cosmological measurements of H0 and σ8. We show here that delaying the onset of neutrino freestreaming until close to the epoch of matter-radiation equality can naturally accommodate a larger value for the Hubble constant H0 = 72.3 ± 1.4 km s −1 Mpc −1 and a lower value of the matter fluctuations σ8 = 0.786 ± 0.020, while not degrading the fit to the cosmic microwave background (CMB) damping tail. We achieve this by introducing neutrino self-interactions in the presence of a nonvanishing sum of neutrino masses. Without explicitly incorporating additional neutrino species, this strongly interacting neutrino cosmology prefers N eff = 4.02 ± 0.29, which has interesting implications for particle model-building and neutrino oscillation anomalies. We show that the absence of the neutrino free-streaming phase shift on the CMB can be compensated by shifting the value of several cosmological parameters, hence providing an important caveat to the detections made in the literature. Due to their impact on the evolution of the gravitational potential at early times, self-interacting neutrinos and their subsequent decoupling leave a rich structure on the matter power spectrum. In particular, we point out the existence of a novel localized feature appearing on scales entering the horizon at the onset of neutrino free-streaming. While the interacting neutrino cosmology provides a better global fit to current cosmological data, we find that traditional Bayesian analyses penalize the model as compared to the standard cosmological scenario due to the relatively narrow range of neutrino interaction strengths that is favored by the data. Our analysis shows that it is possible to find radically different cosmological models that nonetheless provide excellent fits to the data, hence providing an impetus to thoroughly explore alternate cosmological scenarios.

show abstract

Section: Neutrino Interaction Modelmentioning

confidence: 99%

Neutrino puzzle: Anomalies, interactions, and cosmological tensions

2020

View full text Add to dashboard Cite

show abstract

“…The resulting constraints are at the level of f, f 100 keV [93][94][95][96][97]. There are also bounds on the couplings of neutrinos to Goldstone bosons from laboratory experiments, such as neutrinoless double beta decay [98,99], meson decays [93,100], charged lepton decays [101] and tritium decay [102]. These constraints arise from corrections to the energy spectrum of the visible final states due to Goldstone boson emission.…”

Section: Jhep04(2020)020mentioning

confidence: 99%

Cosmological limits on the neutrino mass and lifetime

Chacko

Dev

et al. 2020

J. High Energ. Phys.

117

View full text Add to dashboard Cite

At present, the strongest upper limit on m ν , the sum of neutrino masses, is from cosmological measurements. However, this bound assumes that the neutrinos are stable on cosmological timescales, and is not valid if the neutrino lifetime is less than the age of the universe. In this paper, we explore the cosmological signals of theories in which the neutrinos decay into invisible dark radiation on timescales of order the age of the universe, and determine the bound on the sum of neutrino masses in this scenario. We focus on the case in which the neutrinos decay after becoming non-relativistic. We derive the Boltzmann equations that govern the cosmological evolution of density perturbations in the case of unstable neutrinos, and solve them numerically to determine the effects on the matter power spectrum and lensing of the cosmic microwave background. We find that the results admit a simple analytic understanding. We then use these results to perform a Monte Carlo analysis based on the current data to determine the limit on the sum of neutrino masses as a function of the neutrino lifetime. We show that in the case of decaying neutrinos, values of m ν as large as 0.9 eV are still allowed by the data. Our results have important implications for laboratory experiments that have been designed to detect neutrino masses, such as KATRIN and KamLAND-ZEN.

show abstract

“…• Tritium decay. If the scalar mass m φ O(10 eV), it can be produced from tritium decay in the process 3 H → 3 He + + e − + ν + φ [112], and this process can be probed in the KATRIN experiment [113,114].…”

Section: Other Limitsmentioning

confidence: 99%

Leptonic scalars at the LHC

Gouvêa

Dev²,

Dutta

et al. 2020

J. High Energ. Phys.

View full text Add to dashboard Cite

We explore the collider prospects of neutrino non-standard interaction with a Standard Model (SM) gauge-singlet leptonic scalar φ carrying two units of lepton-numbercharge. These leptonic scalars are forbidden from interacting with the SM fermions at the renormalizable level and, if one allows for higher-dimensional operators, couple predominantly to SM neutrinos. For masses at or below the electroweak scale, φ decays exclusively into neutrinos. Its characteristic production signature at hadron collider experiments like the LHC would be via the vector boson fusion process and leads to same-sign dileptons, two forward jets in opposite hemispheres, and missing transverse energy, i.e., pp → ± α ± β jj + E miss T (α, β = e, µ, τ). Exploiting the final states of electrons and muons, we estimate, for the first time, the sensitivity of the LHC to these lepton-number-charged scalars. We show that the LHC sensitivity is largely complementary to that of low-energy precision measurements of the decays of charged leptons, charged mesons, W , Z and the SM Higgs boson, as well as the neutrino beam experiments like MINOS, and searches for neutrino self-interactions at IceCube and in cosmological observations. For φ mass larger than roughly 10 GeV, our projected LHC sensitivity would surpass all existing bounds.

show abstract

Tritium beta decay with additional emission of new light bosons

Cited by 27 publications

References 94 publications

Neutrino puzzle: Anomalies, interactions, and cosmological tensions

Neutrino puzzle: Anomalies, interactions, and cosmological tensions

Cosmological limits on the neutrino mass and lifetime

Leptonic scalars at the LHC

Contact Info

Product

Resources

About