P. Kopciewicz

activity

20102026

most citedObservation of structure in the

J / ψ

-pair mass spectrum

414 citations · 5.6k across the 200 of their papers we have counts for

collaborators

203 papers

hep-ex2026

Branching fraction measurement of the $B^{0} \to K^{+} π^{-} μ^{+} μ^{-}$ decay at high dihadron mass

LHCb collaboration, R. Aaij, M. Abdelfatah +1103

This Letter presents the first measurement of the $B^{0} \to K^{+} π^{-} μ^{+} μ^{-}$ differential branching fraction in the region of the dihadron $K^{+} π^{-}$ mass, $m_{K π}$ , $1000< m_{…

hep-ex2026

Leakage current evolution in LHCb VELO sensors during Run 1-2 LHC data taking period

M. Pycior, T. Szumlak, A. Oblakowska-Mucha +33

Silicon detectors operating in the harsh mixed-hadron radiation environment of modern high-energy physics experiments suffer progressive bulk damage, manifesting macroscopically as…

nucl-ex2026

Measurement of the average transverse momentum of forward prompt charged particles in $pp$ and $p Pb$ collisions at $s_{N N} = 5.02 TeV$

LHCb collaboration, R. Aaij, M. Abdelfatah +1106

This letter presents the first measurements of the average transverse momentum of prompt charged particles in $pp$ and $p Pb$ collisions as a function of collision multipli…

hep-ex2026

Search for $B$ meson decays to multimuon final states

LHCb collaboration, R. Aaij, M. Abdelfatah +1109

A search for decays of $B$ mesons to final states with four or six muons using $pp$ collision data recorded by the LHCb experiment corresponding to an integrated luminosity of $5.4…

hep-ex2026

Study of muon-tagged $D_{s 1} (2460)^{+}$ and $D_{s 1} (2536)^{+}$ decays to the $D_{s}^{+} π^{+} π^{-}$ final state

LHCb collaboration, R. Aaij, M. Abdelfatah +1119

Decays of the pseudovector $D_{s 1} (2460)^{+}$ and $D_{s 1} (2536)^{+}$ mesons to the three-body $D_{s}^{+} π^{+} π^{-}$ final state are studied. The data sample is based on decays of beauty hadr…

hep-ex2026

Improved measurement of $C P$ violation in $B_{s}^{0} \to J / ψ π^{+} π^{-}$ decays

LHCb collaboration, R. Aaij, M. Abdelfatah +1116

The time-dependent $C P$ asymmetry in $B_{s}^{0} \to J / ψ π^{+} π^{-}$ decays is measured using proton-proton collision data, corresponding to an integrated luminosity of $6\,\text…

hep-ex2026

Observation of several sources of $C P$ violation in $B^{+} \to K^{+} π^{+} π^{-}$ decays

LHCb collaboration, R. Aaij, M. Abdelfatah +1116

An amplitude analysis of $B^{+} \to K^{+} π^{+} π^{-}$ decays is presented in which six $C P$ -violating phenomena are judged to be of significance for the first time. This analysis is b…

hep-ex2026

Resolution of outstanding puzzles in $B^{+} \to K^{+} π^{+} π^{-}$ decays

LHCb collaboration, R. Aaij, M. Abdelfatah +1116

An amplitude analysis of $B^{+} \to K^{+} π^{+} π^{-}$ decays is presented, based on $pp$ collision data recorded with the LHCb detector in 2011--2012, corresponding to an integrated lum…

hep-ex2026

Amplitude analysis of $B^{+} \to K^{+} π^{+} π^{-}$ decays

LHCb collaboration, R. Aaij, M. Abdelfatah +1116

The branching fractions and quasi-two-body $C P$ -violating asymmetries of intermediate states obtained through an amplitude analysis of the charmless three-body decay $B^+ \!\to K…

hep-ex2026

Search for $C P$ violation in $D^{+} \to ϕ π^{+}$ decays

LHCb collaboration, R. Aaij, M. Abdelfatah +1106

A search for charge-parity ( $C P$ ) violation in the Cabibbo-suppressed $D^{+} \to ϕ π^{+}$ decay is presented, using proton-proton collision data corresponding to an integrated luminos…

hep-ex2026

Search for the decays $B_{(c)}^{+} \to μ^{+} ν_{μ} γ$

LHCb collaboration, R. Aaij, M. Abdelfatah +1128

A search for the radiative leptonic decays $B^{+} \to μ^{+} ν_{μ} γ$ and $B_{c}^{+} \to μ^{+} ν_{μ} γ$ is performed using proton-proton collision data collected with the LHCb experiment at a center-of-m…

hep-ex2026

Observation of new excited $Σ_{c}^{0}$ states in the $B^{-} \to Λ_{c}^{+} p π^{-}$ decay

LHCb collaboration, R. Aaij, M. Abdelfatah +1100

An amplitude analysis of the $B^{-} \to Λ_{c}^{+} p π^{-}$ decay is performed using proton-proton collision data, corresponding to an integrated luminosity of $9\text{…

hep-ex2026

Differential measurement of the branching fraction and $C P$ asymmetry of the decay $B^{\pm} \to π^{\pm} μ^{+} μ^{-}$

LHCb collaboration, R. Aaij, M. Abdelfatah +1121

Differential measurements of the branching fraction and $C P$ asymmetry of the decay $B^{\pm} \to π^{\pm} μ^{+} μ^{-}$ are performed in intervals of the dimuon mass squared, $q^{2}$ , using pro…

hep-ex2026

Measurement of the ratio of branching fractions $B (B_{c}^{+} \to J / ψ τ^{+} ν_{τ}) / B (B_{c}^{+} \to J / ψ μ^{+} ν_{μ})$

LHCb collaboration, R. Aaij, M. Abdelfatah +1121

A measurement of the ratio of semileptonic branching fractions $R (J ψ)$ , defined as $\mathcal{R}(J/ψ) \equiv \mathcal{B}(B_c^+ \to J/ψτ^+ ν_τ)/\mathcal{B}(B_c^+ \to J/ψμ^+…

nucl-ex2026

Study of nuclear effects on charm production in light-ion collisions

LHCb collaboration, R. Aaij, M. Abdelfatah +1106

The onset of nuclear effects in light-ion collisions is studied by measuring the ratio of $D^{0}$ meson production between NeNe and OO collisions at a center-of-mass energy per nucle…

hep-ex2026

Evidence for the decay $B_{s}^{0} \to ϕ η^{'}$

LHCb collaboration, R. Aaij, M. Abdelfatah +1101

Using a dataset corresponding to an integrated luminosity of $9 fb^{- 1}$ collected in proton-proton collisions between 2011 and 2018 by the LHCb experiment, evidence is…

hep-ex2026

$C P$ violation analysis of local and nonlocal amplitudes in the $B^{0} \to K^{* 0} μ^{+} μ^{-}$ decay

LHCb collaboration, R. Aaij, M. Abdelfatah +1104

A search for $C P$ violation in the $B^{0} \to K^{* 0} μ^{+} μ^{-}$ decay is performed using proton-proton collision data collected by the LHCb experiment during Run…

hep-ex2026

Observation of the charmless purely baryonic decay $Λ_{b}^{0} \to Λ p p$

LHCb collaboration, R. Aaij, M. Abdelfatah +1103

A search for the charmless purely baryonic decay $Λ_{b}^{0} \to Λ p p$ is performed using proton-proton collision data recorded by the LHCb experi…

hep-ex2026

Measurement of $γ$ using $B^{\pm} \to D K^{\pm}$ and $B^{\pm} \to D π^{\pm}$ decays with $D \to K_{S}^{0} π^{+} π^{-}$ and $D \to K_{S}^{0} K^{+} K^{-}$

LHCb collaboration, R. Aaij, M. Abdelfatah +1105

A measurement of the CKM angle $γ$ using the decay channels $B^{\pm} \to D K^{\pm}$ and $B^{\pm} \to D π^{\pm}$ , where the $D$ meson decays to $D\rightarrow K_{\rm S}^{…

hep-ex2026

Angular analysis of the $B^{+} \to π^{+} μ^{+} μ^{-}$ decay

LHCb collaboration, R. Aaij, M. Abdelfatah +1112

This paper presents the first measurement of the forward-backward asymmetry, $A_{FB}$ , and the flat term, $F_{H}$ , that parameterise the angular distribution of the $B^+\toπ^+μ…

hep-ex2026

Observation of a new excited charm-strange meson $D_{s 1} (2933)^{+}$ in $B^{0} \to D^{+} D^{-} K^{+} π^{-}$ decays

LHCb collaboration, R. Aaij, M. Abdelfatah +1114

A new excited charm-strange meson is observed through an amplitude analysis of the full phase space of $B^{0} \to D^{+} D^{-} K^{+} π^{-}$ decays. The analysis is based on a proton-proton col…

hep-ex2026

Measurement of the $W$ -boson production cross-sections in $pp$ collisions at $s$ = 13 TeV in the forward region

LHCb collaboration, R. Aaij, M. Abdelfatah +1114

A precision measurement of the $W$ -boson production cross-section is performed using the $W \to μν$ decay channel, based on a sample of proton-proton collision data collected by th…

hep-ex2026

Precision measurement of the muon charge asymmetry from $W$ -boson decays in $pp$ collisions at $s$ = 13 TeV in the forward region

LHCb collaboration, R. Aaij, M. Abdelfatah +1114

A precision measurement of the muon charge asymmetry from $W$ -boson decays in proton-proton collisions at $s$ = 13 TeV is presented. The analysis utilizes data corresponding…

hep-ex2026

Search for the lepton-flavour violating decays $B^{+} \to π^{+} μ^{\pm} e^{\mp}$

LHCb collaboration, R. Aaij, M. Abdelfatah +1106

The first search for the lepton-flavour violating decays $B^{+} \to π^{+} μ^{\pm} e^{\mp}$ in proton-proton collisions is presented, using data collected by the LHCb experiment between…

Branching fraction measurement of the B0→K+π−μ+μ− decay at high dihadron mass

Leakage current evolution in LHCb VELO sensors during Run 1-2 LHC data taking period

Measurement of the average transverse momentum of forward prompt charged particles in pp and pPb collisions at sNN​​=5.02TeV

Search for B meson decays to multimuon final states

Study of muon-tagged Ds1​(2460)+ and Ds1​(2536)+ decays to the Ds+​π+π− final state

Improved measurement of CP violation in Bs0​→J/ψπ+π− decays

Observation of several sources of CP violation in B+→K+π+π− decays

Resolution of outstanding puzzles in B+→K+π+π− decays

Amplitude analysis of B+→K+π+π− decays

Search for CP violation in D+→ϕπ+ decays

Search for the decays B(c)+​→μ+νμ​γ

Observation of new excited Σc0​ states in the B−→Λc+​p​π− decay

Differential measurement of the branching fraction and CP asymmetry of the decay B±→π±μ+μ−

Measurement of the ratio of branching fractions B(Bc+​→J/ψτ+ντ​)/B(Bc+​→J/ψμ+νμ​)

Study of nuclear effects on charm production in light-ion collisions

Evidence for the decay Bs0​→ϕη′

CP violation analysis of local and nonlocal amplitudes in the B0→K∗0μ+μ− decay

Observation of the charmless purely baryonic decay Λb0​→Λpp​

Measurement of γ using B±→DK± and B±→Dπ± decays with D→KS0​π+π− and D→KS0​K+K−

Angular analysis of the B+→π+μ+μ− decay

Observation of a new excited charm-strange meson Ds1​(2933)+ in B0→D+D−K+π− decays

Measurement of the W-boson production cross-sections in pp collisions at s​ = 13 TeV in the forward region

Precision measurement of the muon charge asymmetry from W-boson decays in pp collisions at s​ = 13 TeV in the forward region

Search for the lepton-flavour violating decays B+→π+μ±e∓

Branching fraction measurement of the $B^{0} \to K^{+} π^{-} μ^{+} μ^{-}$ decay at high dihadron mass

Measurement of the average transverse momentum of forward prompt charged particles in $pp$ and $p Pb$ collisions at $s_{N N} = 5.02 TeV$

Search for $B$ meson decays to multimuon final states

Study of muon-tagged $D_{s 1} (2460)^{+}$ and $D_{s 1} (2536)^{+}$ decays to the $D_{s}^{+} π^{+} π^{-}$ final state

Improved measurement of $C P$ violation in $B_{s}^{0} \to J / ψ π^{+} π^{-}$ decays

Observation of several sources of $C P$ violation in $B^{+} \to K^{+} π^{+} π^{-}$ decays

Resolution of outstanding puzzles in $B^{+} \to K^{+} π^{+} π^{-}$ decays

Amplitude analysis of $B^{+} \to K^{+} π^{+} π^{-}$ decays

Search for $C P$ violation in $D^{+} \to ϕ π^{+}$ decays

Search for the decays $B_{(c)}^{+} \to μ^{+} ν_{μ} γ$

Observation of new excited $Σ_{c}^{0}$ states in the $B^{-} \to Λ_{c}^{+} p π^{-}$ decay

Differential measurement of the branching fraction and $C P$ asymmetry of the decay $B^{\pm} \to π^{\pm} μ^{+} μ^{-}$

Measurement of the ratio of branching fractions $B (B_{c}^{+} \to J / ψ τ^{+} ν_{τ}) / B (B_{c}^{+} \to J / ψ μ^{+} ν_{μ})$

Evidence for the decay $B_{s}^{0} \to ϕ η^{'}$

$C P$ violation analysis of local and nonlocal amplitudes in the $B^{0} \to K^{* 0} μ^{+} μ^{-}$ decay

Observation of the charmless purely baryonic decay $Λ_{b}^{0} \to Λ p p$

Measurement of $γ$ using $B^{\pm} \to D K^{\pm}$ and $B^{\pm} \to D π^{\pm}$ decays with $D \to K_{S}^{0} π^{+} π^{-}$ and $D \to K_{S}^{0} K^{+} K^{-}$

Angular analysis of the $B^{+} \to π^{+} μ^{+} μ^{-}$ decay

Observation of a new excited charm-strange meson $D_{s 1} (2933)^{+}$ in $B^{0} \to D^{+} D^{-} K^{+} π^{-}$ decays

Measurement of the $W$ -boson production cross-sections in $pp$ collisions at $s$ = 13 TeV in the forward region

Precision measurement of the muon charge asymmetry from $W$ -boson decays in $pp$ collisions at $s$ = 13 TeV in the forward region

Search for the lepton-flavour violating decays $B^{+} \to π^{+} μ^{\pm} e^{\mp}$