D. Bryman

activity

19952025

most citedFlavour physics of leptons and dipole moments

378 citations · 2.9k across the 65 of their papers we have counts for

collaborators

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48 papers · 1 filter

hep-ex2025

Searches for hidden sectors using $K^{+} \to π^{+} X$ decays

NA62 Collaboration

Results from the study of the rare decays $K^{+} \to π^{+} ν ν ˉ$ , $K^{+} \to π^{+} μ^{+} μ^{-}$ and $K^{+} \to π^{+} γ γ$ at the NA62 experiment at CERN are interpreted in terms…

hep-ex2025★ 2 cited

Search for heavy neutral leptons in $π^{+}$ decays to positrons

NA62 Collaboration

A search for heavy neutral lepton ( $N$ ) production in $π^{+} \to e^{+} N$ in-flight decays using data collected by the NA62 experiment at CERN in 2017-2024 is reported. Upper limits for…

hep-ex2025

European Strategy for Particle Physics Update -- PIONEER: a next generation rare pion decay experiment

PIONEER Collaboration, A. Adelmann, W. Altmannshofer +76

PIONEER is a rapidly developing effort aimed to perform a pristine test of lepton flavour universality (LFU) and of the unitarity of the first row of the CKM matrix by significantl…

hep-ex2025★ 5 cited

Search for hadronic decays of feebly-interacting particles at NA62

NA62 Collaboration

The NA62 experiment at CERN has the capability to collect data in a beam-dump mode, where 400 GeV protons are dumped on an absorber. In this configuration, New Physics particles, i…

hep-ex2024★ 13 cited

Observation of the $K^{+} \to π^{+} ν ν ˉ$ decay and measurement of its branching ratio

NA62 Collaboration

A measurement of the $K^{+} \to π^{+} ν ν ˉ$ decay by the NA62 experiment at the CERN SPS is presented, using data collected in 2021 and 2022. This dataset was recorded, afte…

hep-ex2024★ 3 cited

First detection of a tagged neutrino in the NA62 experiment

NA62 Collaboration

The NA62 experiment at the CERN SPS reports the first detection of a tagged neutrino candidate based on the data collected in 2022. The candidate consists of a $K^+ \rightarrow μ^+…

hep-ex2024

Measurement of the response function of the PIENU calorimeter

A. Aguilar-Arevalo, M. Aoki, M. Blecher +17

Measurements of the response function of the PIENU NaI(T $ℓ$ ) and CsI crystal calorimeter using a monochromatic 70 MeV/c positron beam at various incidence angles are described.…

hep-ex2023

Development of a new CEDAR for kaon identification at the NA62 experiment at CERN

The NA62 Collaboration

The NA62 experiment at CERN utilises a differential Cherenkov counter with achromatic ring focus (CEDAR) for tagging kaons within an unseparated monochromatic beam of charged hadro…

hep-ex2023★ 10 cited

Search for Leptonic Decays of Dark Photons at NA62

The NA62 collaboration

The NA62 experiment at CERN, configured in beam-dump mode, has searched for dark photon decays in flight to electron-positron pairs using a sample of $1.4 \times 1 0^{17}$ protons on…

hep-ex2022★ 15 cited

A measurement of the $K^{+} \to π^{+} μ^{+} μ^{-}$ decay

NA62 Collaboration

A sample of $2.8 \times 1 0^{4}$ $K^{+} \to π^{+} μ^{+} μ^{-}$ candidates with negligible background was collected by the NA62 experiment at the CERN SPS in 2017--2018. The model-inde…

hep-ex2022★ 3 cited

Performance of the NA62 trigger system

The NA62 Collaboration

The NA62 experiment at CERN targets the measurement of the ultra-rare $K^{+} \to π^{+} ν ν ˉ$ decay, and carries out a broad physics programme that includes probes for symmetry vio…

hep-ex2022★ 9 cited

Testing Lepton Flavor Universality and CKM Unitarity with Rare Pion Decays in the PIONEER experiment

PIONEER Collaboration, W. Altmannshofer, H. Binney +58

The physics motivation and the conceptual design of the PIONEER experiment, a next-generation rare pion decay experiment testing lepton flavor universality and CKM unitarity, are d…

hep-ex2022★ 14 cited

PIONEER: Studies of Rare Pion Decays

PIONEER Collaboration, W. Altmannshofer, H. Binney +58

A next-generation rare pion decay experiment, PIONEER, is strongly motivated by several inconsistencies between Standard Model (SM) predictions and data pointing towards the potent…

hep-ex2022★ 19 cited

Searches for lepton number violating $K^{+} \to π^{-} (π^{0}) e^{+} e^{+}$ decays

NA62 collaboration

Searches for lepton number violating $K^{+} \to π^{-} e^{+} e^{+}$ and $K^{+} \to π^{-} π^{0} e^{+} e^{+}$ decays have been performed using the complete dataset collected by the NA62 experiment at CERN in 20…

hep-ex2021★ 28 cited

Search for lepton number and flavour violation in $K^{+}$ and $π^{0}$ decays

NA62 Collaboration

Searches for the lepton number violating $K^{+} \to π^{-} μ^{+} e^{+}$ decay and the lepton flavour violating $K^{+} \to π^{+} μ^{-} e^{+}$ and $π^{0} \rightarrow μ…

hep-ex2021★ 155 cited

Measurement of the very rare $K^{+} \to π^{+} ν ν ˉ$ decay

NA62 Collaboration

The NA62 experiment reports the branching ratio measurement BR $(K^{+} \to π^{+} ν ν ˉ) = (10. 6_{- 3.4}^{+ 4.0} ∣_{stat} \pm 0. 9_{syst}) \times 1 0^{- 11}$ at 68% CL, base…

hep-ex2021★ 25 cited

Search for three body pion decays $π^{+} \to l^{+} ν X$

A. Aguilar-Arevalo, M. Aoki, M. Blecher +21

The three body pion decays $π^{+} \to l^{+} ν X (l = e, μ)$ , where $X$ is a weakly interacting neutral boson, were searched for using the full data set from the PIENU experiment. An…

hep-ex2020★ 9 cited

Search for a feebly interacting particle $X$ in the decay $K^{+} \to π^{+} X$

NA62 Collaboration

A search for the $K^{+} \to π^{+} X$ decay, where $X$ is a long-lived feebly interacting particle, is performed through an interpretation of the $K^{+} \to π^{+} ν ν ˉ$ …

hep-ex2020★ 82 cited

Search for heavy neutral lepton production in $K^{+}$ decays to positrons

NA62 collaboration

A search for heavy neutral lepton ( $N$ ) production in $K^{+} \to e^{+} N$ decays using the data sample collected by the NA62 experiment at CERN in 2017--2018 is reported. Upper limits of…

hep-ex2020★ 1 cited

Search for the rare decays $π^{+} \to μ^{+} ν_{μ} ν ν ˉ$ and $π^{+} \to e^{+} ν_{e} ν ν ˉ$

A. Aguilar-Arevalo, M. Aoki, M. Blecher +23

The rare pion decays $π^{+} \to μ^{+} ν_{μ} ν ν ˉ$ and $π^{+} \to e^{+} ν_{e} ν ν ˉ$ are allowed in the Standard Model but highly suppressed. These decays were searched for usi…

hep-ex2020★ 17 cited

Improved search for two body muon decay $μ^{+} \to e^{+} X_{H}$

A. Aguilar-Arevalo, M. Aoki, M. Blecher +21

Charged lepton flavor violating muon decay $μ^{+} \to e^{+} X_{H}$ , where $X_{H}$ is a massive neutral boson, was sought by searching for extra peaks in the muon decay $μ^+{\rightar…

hep-ex2019★ 46 cited

Searches for lepton number violating $K^{+}$ decays

NA62 collaboration

The NA62 experiment at CERN reports a search for the lepton number violating decays $K^{+} \to π^{-} e^{+} e^{+}$ and $K^{+} \to π^{-} μ^{+} μ^{+}$ using a data sample collected in 2017. No signals are ob…

hep-ex2019★ 65 cited

Search for Heavy Neutrinos in $π \to μν$ Decay

A. Aguilar-Arevalo, M. Aoki, M. Blecher +21

Heavy neutrinos were sought in pion decays $π^{+} \to μ^{+} ν$ by examining the observed muon energy spectrum for extra peaks in addition to the expected peak for a massless ne…

hep-ex2019★ 72 cited

Search for production of an invisible dark photon in $π^{0}$ decays

NA62 collaboration

The results of a search for $π^{0}$ decays to a photon and an invisible massive dark photon at the NA62 experiment at the CERN SPS are reported. From a total of $4.12 \times 1 0^{8}$ tagg…

Searches for hidden sectors using K+→π+X decays

Search for heavy neutral leptons in π+ decays to positrons

European Strategy for Particle Physics Update -- PIONEER: a next generation rare pion decay experiment

Search for hadronic decays of feebly-interacting particles at NA62

Observation of the K+→π+ννˉ decay and measurement of its branching ratio

First detection of a tagged neutrino in the NA62 experiment

Measurement of the response function of the PIENU calorimeter

Development of a new CEDAR for kaon identification at the NA62 experiment at CERN

Search for Leptonic Decays of Dark Photons at NA62

A measurement of the K+→π+μ+μ− decay

Performance of the NA62 trigger system

Testing Lepton Flavor Universality and CKM Unitarity with Rare Pion Decays in the PIONEER experiment

PIONEER: Studies of Rare Pion Decays

Searches for lepton number violating K+→π−(π0)e+e+ decays

Search for lepton number and flavour violation in K+ and π0 decays

Measurement of the very rare K+→π+ννˉ decay

Search for three body pion decays π+→l+νX

Search for a feebly interacting particle X in the decay K+→π+X

Search for heavy neutral lepton production in K+ decays to positrons

Search for the rare decays π+→μ+νμ​ννˉ and π+→e+νe​ννˉ

Improved search for two body muon decay μ+→e+XH​

Searches for lepton number violating K+ decays

Search for Heavy Neutrinos in π→μν Decay

Search for production of an invisible dark photon in π0 decays

Searches for hidden sectors using $K^{+} \to π^{+} X$ decays

Search for heavy neutral leptons in $π^{+}$ decays to positrons

Observation of the $K^{+} \to π^{+} ν ν ˉ$ decay and measurement of its branching ratio

A measurement of the $K^{+} \to π^{+} μ^{+} μ^{-}$ decay

Searches for lepton number violating $K^{+} \to π^{-} (π^{0}) e^{+} e^{+}$ decays

Search for lepton number and flavour violation in $K^{+}$ and $π^{0}$ decays

Measurement of the very rare $K^{+} \to π^{+} ν ν ˉ$ decay

Search for three body pion decays $π^{+} \to l^{+} ν X$

Search for a feebly interacting particle $X$ in the decay $K^{+} \to π^{+} X$

Search for heavy neutral lepton production in $K^{+}$ decays to positrons

Search for the rare decays $π^{+} \to μ^{+} ν_{μ} ν ν ˉ$ and $π^{+} \to e^{+} ν_{e} ν ν ˉ$

Improved search for two body muon decay $μ^{+} \to e^{+} X_{H}$

Searches for lepton number violating $K^{+}$ decays

Search for Heavy Neutrinos in $π \to μν$ Decay

Search for production of an invisible dark photon in $π^{0}$ decays