F. Keizer

activity

20172026

most citedObservation of an exotic narrow doubly charmed tetraquark

403 citations · 3k across the 94 of their papers we have counts for

collaborators

94 papers

hep-ex2026

Observation of the decay $χ_{c 1} (3872) \to J / ψ μ^{+} μ^{-}$

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1184

The first observation of the $χ_{c 1} (3872) \to J / ψ μ^{+} μ^{-}$ decay is reported using proton-proton collision data recorded with the LHCb detector correspo…

hep-ex2026

Search for lepton-number-violating $B^{-} \to D^{(*) +} μ^{-} μ^{-}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1188

A search is performed for lepton-number-violating $B^{-} \to D^{(*) +} μ^{-} μ^{-}$ decays, using data collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy…

hep-ex2025★ 1 cited

First observation of the $B_{s}^{0} \to Λ_{c}^{+} Λ_{c}^{-}$ decay and evidence for the $B^{0} \to Λ_{c}^{+} Λ_{c}^{-}$ decay

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1187

A search is presented for the two-body charmed baryonic decays $B_{(s)}^{0} \to Λ_{c}^{+} Λ_{c}^{-}$ , using a data sample collected by the LHCb experiment during…

hep-ex2025

Differential decay rate of $B^{+} \to J / ψ K^{+}$ with the LHCb Upgrade I experiment

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1183

The normalised decay rate of $B^{+} \to J / ψ (\to μ^{+} μ^{-}) K^{+}$ is measured as a function of the lepton helicity angle using a data sample corresponding to an integrated luminosity of $…

hep-ex2025★ 1 cited

Branching fraction measurement of the $Λ \to p μ^{-} ν_{μ}$ decay

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1187

A measurement of the branching fraction for the decay $Λ \to p μ^{-} ν_{μ}$ is presented using $pp$ collision data collected by the LHCb experiment at a centre…

hep-ex2025★ 1 cited

Measurement of $C P$ asymmetry in $D^{0} \to K_{S}^{0} K_{S}^{0}$ decays with Run 3 data

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1189

A measurement of $C P$ asymmetry in $D^{0} \to K_{S}^{0} K_{S}^{0}$ decays is reported, based on a data sample of proton-proton collisions collected with the LHCb detector in 20…

hep-ex2025★ 1 cited

Searches for $B^{0} \to K^{+} π^{-} τ^{+} τ^{-}$ and $B_{s}^{0} \to K^{+} K^{-} τ^{+} τ^{-}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1185

The first searches for $B^{0} \to K^{+} π^{-} τ^{+} τ^{-}$ and $B_{s}^{0} \to K^{+} K^{-} τ^{+} τ^{-}$ decays at the LHCb experiment are conducted with $pp$ collision data corresponding to an integrated luminos…

hep-ex2025

Measurement of the $W \to μ ν_{μ}$ cross-sections as a function of the muon transverse momentum in $pp$ collisions at 5.02 TeV

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1186

The $pp \to W^{\pm} (\to μ^{\pm} ν_{μ}) X$ cross-sections are measured at a proton-proton centre-of-mass energy $s = 5.02$ TeV using a dataset corresponding to an integrated l…

hep-ex2025★ 2 cited

First evidence of $C P$ violation in beauty baryon to charmonium decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1178

A study of the difference in the $C P$ asymmetries between $Λ_{b}^{0} \to J / ψ p π^{-}$ and $Λ_{b}^{0} \to J / ψ p K^{-}$ decays, $Δ A_{C P}$ , is performed using proton-prot…

hep-ex2025★ 2 cited

Observation of $B_{c}^{+} \to D h^{+} h^{-}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1185

Searches are presented for $B_{c}^{+} \to D h^{+} h^{-}$ decays, where $D$ is a charmed meson and $h^{\pm}$ is a charged pion or kaon, using $pp$ collision data collected by the LHCb e…

hep-ex2025★ 1 cited

Measurement of the branching fraction of the $Λ_{b}^{0} \to J / ψ Λ$ decay and isospin asymmetry of $B \to J / ψ K$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1193

This paper describes a measurement of the $Λ_{b}^{0} \to J / ψ Λ$ branching fraction using data collected with the LHCb experiment in proton-proton collisions from 2016 to 2018. The datase…

hep-ex2025

Amplitude analysis of $B^{0} \to η_{c} (1 S) K^{+} π^{-}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1185

An amplitude analysis of the $B^{0} \to η_{c} (1 S) K^{+} π^{-}$ decays with $η_{c} (1 S) \to p p ˉ$ is performed using a sample corresponding to an integrated luminosity of 9$\…

hep-ex2025

Inclusive $B$ -meson flavour-tagging algorithm at LHCb

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1179

A new algorithm is developed to identify the flavour of neutral $B$ mesons at production in $pp$ collisions by utilising all tracks from the hadronisation process. The algorithm is…

hep-ex2025★ 3 cited

Measurement of branching fractions and $C P$ asymmetries in $Λ_{b}^{0} (Ξ_{b}^{0}) \to p K_{S}^{0} h^{-}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1160

A study of $Λ_{b}^{0}$ and $Ξ_{b}^{0}$ baryon decays to the final states $p K_{S}^{0} π^{-}$ and $p K_{S}^{0} K^{-}$ is performed using $pp$ collision data collected by t…

hep-ex2025★ 1 cited

First observation of the charmless baryonic decay $B^{+} \to Λ ˉ p p ˉ p$

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1186

A search for the charmless baryonic decay $B^{+} \to Λ ˉ p p ˉ p$ is performed using proton-proton collision data recorded by the LHCb experiment, corresponding to an integrated l…

hep-ex2025★ 2 cited

First observation of $C P$ violation and measurement of polarization in $B^{+} \to ρ (770)^{0} K^{*} (892)^{+}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1183

An amplitude analysis of the $B^{+} \to (π^{+} π^{-}) (K_{S}^{0} π^{+})$ decay is performed in the mass regions $0.30 < m_{π^{+} π^{-}} < 1.10 GeV / c^{2}$ and $0.75 < m_{K^0_{\mathrm{S…

hep-ex2025

Deuteron identification via time of flight with LHCb

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1183

It is shown that the timing capabilities of the LHCb detector operated during the LHC Run 2 can be used to identify light ion particles with momenta of a few GeV/ $c$ . This is achie…

hep-ex2025★ 1 cited

Improved measurement of $η / η^{'}$ mixing in $B_{(s)}^{0} \to J / ψ η^{(')}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1182

Branching fraction ratios between the decays $B_{(s)}^{0} \to J / ψ η^{(')}$ are measured using proton-proton collision data collected by the LHCb experiment at centre-of…

hep-ex2025

Precision measurement of the $Ξ_{b}^{0}$ baryon lifetime

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1176

A sample of $pp$ collision data, corresponding to an integrated luminosity of 5.4 fb $^{- 1}$ and collected by the LHCb experiment during LHC Run 2, is used to measure the ratio of t…

hep-ex2025★ 2 cited

First observation of the $Λ_{b}^{0} \to Λ_{c}^{+} D_{s}^{-} K^{+} K^{-}$ decay and search for pentaquarks in the $Λ_{c}^{+} D_{s}^{-}$ system

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1176

The $Λ_{b}^{0} \to Λ_{c}^{+} D_{s}^{-} K^{+} K^{-}$ decay is observed for the first time using the data sample from proton-proton collisions recorded at a center-o…

hep-ex2025

Updated measurement of $C P$ violation and polarisation in $B_{s}^{0} \to J / ψ K^{*} (892)^{0}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1169

A time-integrated angular analysis of the decay $B_{s}^{0} \to J / ψ K^{*} (892)^{0}$ , with $J / ψ \to μ^{+} μ^{-}$ and $\overline{K}{}^{*}\kern-1pt(892)…

hep-ex2025★ 1 cited

Measurement of the Z-boson mass

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1129

The first dedicated $Z$ -boson mass measurement at the LHC with $Z \to μ^{+} μ^{-}$ decays is reported. The dataset uses proton-proton collisions at a centre-of-mass energy of $13$ TeV,…

hep-ex2025★ 4 cited

Luminosity measurement with the LHCb RICH detectors in Run 3

Paula Alvarez Cartelle, Alessia Anelli, Anna Balboni +58

The LHCb Ring-Imaging Cherenkov detectors are built to provide charged hadron identification over a large range of momentum. The upgraded detectors are also capable of providing an…

hep-ex2025★ 3 cited

Observation of the $Λ_{b}^{0} \to J / ψ Ξ^{-} K^{+}$ and $Ξ_{b}^{0} \to J / ψ Ξ^{-} π^{+}$ decays

LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +1131

The first observation of the $Ξ_{b}^{0} \to J / ψ Ξ^{-} π^{+}$ decay and the most precise measurement of the branching fraction of the $Λ_{b}^{0} \to J / ψ Ξ^{-} K^{+}$ decay are reported, using proton-…

Observation of the decay χc1​(3872)→J/ψμ+μ−

Search for lepton-number-violating B−→D(∗)+μ−μ− decays

First observation of the Bs0​→Λc+​Λc​− decay and evidence for the B0→Λc+​Λc​− decay

Differential decay rate of B+→J/ψK+ with the LHCb Upgrade I experiment

Branching fraction measurement of the Λ→pμ−νμ​ decay

Measurement of CP asymmetry in D0→KS0​KS0​ decays with Run 3 data

Searches for B0→K+π−τ+τ− and Bs0​→K+K−τ+τ− decays

Measurement of the W→μνμ​ cross-sections as a function of the muon transverse momentum in pp collisions at 5.02 TeV

First evidence of CP violation in beauty baryon to charmonium decays

Observation of Bc+​→Dh+h− decays

Measurement of the branching fraction of the Λb0​→J/ψΛ decay and isospin asymmetry of B→J/ψK decays

Amplitude analysis of B0→ηc​(1S)K+π− decays

Inclusive B-meson flavour-tagging algorithm at LHCb

Measurement of branching fractions and CP asymmetries in Λb0​(Ξb0​)→pKS0​h− decays

First observation of the charmless baryonic decay B+→Λˉppˉ​p

First observation of CP violation and measurement of polarization in B+→ρ(770)0K∗(892)+ decays

Deuteron identification via time of flight with LHCb

Improved measurement of η/η′ mixing in B(s)0​→J/ψη(′) decays

Precision measurement of the Ξb0​ baryon lifetime

First observation of the Λb0​→Λc+​Ds−​K+K− decay and search for pentaquarks in the Λc+​Ds−​ system

Updated measurement of CP violation and polarisation in Bs0​→J/ψK∗(892)0 decays

Measurement of the Z-boson mass

Luminosity measurement with the LHCb RICH detectors in Run 3

Observation of the Λb0​→J/ψΞ−K+ and Ξb0​→J/ψΞ−π+ decays

Observation of the decay $χ_{c 1} (3872) \to J / ψ μ^{+} μ^{-}$

Search for lepton-number-violating $B^{-} \to D^{(*) +} μ^{-} μ^{-}$ decays

First observation of the $B_{s}^{0} \to Λ_{c}^{+} Λ_{c}^{-}$ decay and evidence for the $B^{0} \to Λ_{c}^{+} Λ_{c}^{-}$ decay

Differential decay rate of $B^{+} \to J / ψ K^{+}$ with the LHCb Upgrade I experiment

Branching fraction measurement of the $Λ \to p μ^{-} ν_{μ}$ decay

Measurement of $C P$ asymmetry in $D^{0} \to K_{S}^{0} K_{S}^{0}$ decays with Run 3 data

Searches for $B^{0} \to K^{+} π^{-} τ^{+} τ^{-}$ and $B_{s}^{0} \to K^{+} K^{-} τ^{+} τ^{-}$ decays

Measurement of the $W \to μ ν_{μ}$ cross-sections as a function of the muon transverse momentum in $pp$ collisions at 5.02 TeV

First evidence of $C P$ violation in beauty baryon to charmonium decays

Observation of $B_{c}^{+} \to D h^{+} h^{-}$ decays

Measurement of the branching fraction of the $Λ_{b}^{0} \to J / ψ Λ$ decay and isospin asymmetry of $B \to J / ψ K$ decays

Amplitude analysis of $B^{0} \to η_{c} (1 S) K^{+} π^{-}$ decays

Inclusive $B$ -meson flavour-tagging algorithm at LHCb

Measurement of branching fractions and $C P$ asymmetries in $Λ_{b}^{0} (Ξ_{b}^{0}) \to p K_{S}^{0} h^{-}$ decays

First observation of the charmless baryonic decay $B^{+} \to Λ ˉ p p ˉ p$

First observation of $C P$ violation and measurement of polarization in $B^{+} \to ρ (770)^{0} K^{*} (892)^{+}$ decays

Improved measurement of $η / η^{'}$ mixing in $B_{(s)}^{0} \to J / ψ η^{(')}$ decays

Precision measurement of the $Ξ_{b}^{0}$ baryon lifetime

First observation of the $Λ_{b}^{0} \to Λ_{c}^{+} D_{s}^{-} K^{+} K^{-}$ decay and search for pentaquarks in the $Λ_{c}^{+} D_{s}^{-}$ system

Updated measurement of $C P$ violation and polarisation in $B_{s}^{0} \to J / ψ K^{*} (892)^{0}$ decays

Observation of the $Λ_{b}^{0} \to J / ψ Ξ^{-} K^{+}$ and $Ξ_{b}^{0} \to J / ψ Ξ^{-} π^{+}$ decays