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LHCb Conference Contributions

Ultimi arrivi:
2025-09-18
04:02
Unveiling the shape of the $^{20}$Ne nucleus by measuring the flow coefficients with cumulants in PbNe and PbAr collisions at $\sqrt{s_{NN}} = 70.9$ GeV / LHCb Collaboration
The anisotropic flow coefficients $v_n$ quantify the collective medium response to the initial spatial anisotropy of the overlapping region in ion collisions and serve as sensitive probes of both the medium properties and shape of nuclear initial states. [...]
arXiv:2509.12399 ; LHCb-CONF-2025-001.
- 19.
Fulltext

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2025-09-15
17:27
Branching fractions of $\eta$ and $\eta’(958)$ anomalous decays at LHCb /LHCb Collaboration
Branching fractions of $\eta$ and $\eta’(958)$ anomalous decays are measured using $pp$ collision data at a center-of-mass energy of $\sqrt{s}=13\,\mathrm{TeV}$ collected by the LHCb experiment and corresponding to an integrated luminosity of $5.4\,\mathrm{fb^{-1}}$. The measured values and upper limits at the 90% confidence level are \begin{equation} \mathcal{B}(\eta\to\mu^+\mu^-) = (5.30\pm0.14_{\text{(stat)}}\pm0.18_{\text{(syst)}}\pm0.26_{\phi})\times10^{-6} \nonumber, \end{equation} \begin{equation} \mathcal{B}(\eta’(958)\to\mu^+\mu^-)<1.94\times10^{-7} \nonumber, \end{equation} \begin{equation} \mathcal{B}(\eta\to\pi^+\pi^-\mu^+\mu^-)<6\times10^{-7} \nonumber, \end{equation} \begin{equation} \mathcal{B}(\eta’(958)\to\pi^+\pi^-\mu^+\mu^-) = (2.80\pm0.14_{\text{(stat)}}\pm0.13_{\text{(syst)}}\pm0.14_{\phi})\times10^{-5} \nonumber, \end{equation} where the first uncertainty is statistical, the second is systematic, and the third is the uncertainty associated with the branching fraction of the $\phi\to\mu^+ \mu^-$ decay which is used for normalization. [...]
LHCb-CONF-2025-002; CERN-LHCb-CONF-2025-002.- Geneva : CERN, 2025 Fulltext: LHCb-CONF-2025-002 - PDF; LHCb-CONF-2025-002_Figures - ZIP;
In : 13th International Workshop on the CKM Unitarity Triangle, Cagliari, It, 15 - 19 Sep 2025

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2025-04-04
10:35
First observation of the $\phi$ (1020) meson in the $K^+K^-$ mass spectrum of ultra-pheripheral PbPb collisions at forward rapidity /LHCb Collaboration
The first observation of the $\phi(1020)$ meson in the invariant-mass distribution of $K^+K^-$ meson pairs produced in ultra-peripheral PbPb interactions at forward rapidity, in the range 2.0-4.5, is presented. The PbPb data were collected by the LHCb experiment in 2018 at a nucleon-nucleon center-of-mass energy $\sqrt{snn}$=5.02 TeV, and correspond to an integrated luminosity of $228\pm10 \mu b^{-1}$. [...]
LHCb-CONF-2024-006; CERN-LHCb-CONF-2024-006.- Geneva : CERN, 2025 Fulltext: LHCb-CONF-2024-006 - PDF; LHCb-CONF-2024-006-figs - ZIP;
In : 31st International Conference on Ultra-relativistic Nucleus-Nucleus Collisions, Frankfurt, De, 6 - 12 Apr 2025

Record dettagliato
2024-07-30
17:34
Antihelium production in $\overline{\it \Lambda}_b^0$ decays /LHCb Collaboration
Decays of $\overline{\Lambda}^{0}_{b}$ baryons produced in dark matter annihilating into $b\overline b$ pairs could enhance the abundance of antihelium in cosmic rays. The LHCb collaboration provides in this paper the first experimental limits on related branching fractions: \begin{align*} \mathcal B({\overline{\it \Lambda}_b^0\to{}^3{\rm\overline He}p p})&<1.9\times10^{-9}\text{ at 90% CL,}\\ \mathcal B({\overline{\it \Lambda}_b^0\to{}^3{\rm\overline He}pp X})&<1.6\times10^{-8}\text{ at 90% CL,}\\ \mathcal B({\overline{\it \Lambda}_b^0\to{}^3{\rm \overline He}pX})&<3.6\times10^{-8}\text{ at 90% CL,} \end{align*} where $X$ denotes one or several particles. [...]
LHCb-CONF-2024-005; CERN-LHCb-CONF-2024-005.- Geneva : CERN, 2024 - 19. - Published in : PoS: ICHEP2024 (2025) , pp. 676 Fulltext: LHCb-CONF-2024-005-figures - ZIP; LHCb-CONF-2024-005 - PDF; ICHEP2024_676 - PDF;
In : 42nd International Conference on High Energy Physics (ICHEP 2024), Prague, Czech Republic, 18 - 24 Jul 2024, pp.676

Record dettagliato
2024-07-26
14:09
Simultaneous determination of the CKM angle $\gamma$ and parameters related to mixing and $C\!P$ violation in the charm sector /LHCb Collaboration
A combination of measurements sensitive to the $C\!P$-violation angle $\gamma$ of the Cabibbo-Kobayashi-Maskawa unitarity triangle, to the charm mixing parameters that describe oscillations between $D^0$ and and $\overline D^0$ mesons, and to the $C\!P$ asymmetries in the $D^0 \!\to K^+ K^-$ and $D^0 \!\to \pi^+ \pi^-$ decays is performed. All relevant beauty and charm results obtained with the data collected with the LHCb detector at CERN's Large Hadron Collider to date are included. [...]
LHCb-CONF-2024-004; CERN-LHCb-CONF-2024-004.- Geneva : CERN, 2024 - 29. Fulltext: LHCb-CONF-2024-004 - PDF; LHCb-CONF-2024-004-figs - ZIP;
In : 42nd International Conference on High Energy Physics (ICHEP 2024), Prague, Czech Republic, 18 - 24 Jul 2024

Record dettagliato
2024-06-06
16:32
Search for $B_{(s)}^{*0}\to\mu^+\mu^-$ in $B_c^+\to\pi^+\mu^+\mu^-$ decays /LHCb Collaboration
A search for the very rare $B^{*0}\to\mu^+\mu^-$ and $B_{s}^{*0}\to\mu^+\mu^-$ decays is conducted by analysing the $B_c^+\to\pi^+\mu^+\mu^-$ process. The analysis uses proton-proton collision data collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9\,fb$^{-1}$. [...]
LHCb-CONF-2024-003; CERN-LHCb-CONF-2024-003.- Geneva : CERN, 2024 - 15. Fulltext: LHCb-CONF-2024-003 - PDF; LHCb-CONF-2024-003.figures - ZIP;
In : 12th Edition of the Large Hadron Collider Physics Conference (LHCP2024), Boston, United States, 3 - 7 Jun 2024, pp.LHCb-CONF-2024-003 ; CERN-LHCb-CONF-2024-003

Record dettagliato
2024-06-06
11:11
Observation of the $\Sigma^+ \to p \mu^+ \mu^-$ rare decay at LHCb /LHCb Collaboration
The first observation of the $\Sigma^+ \to p \mu^+ \mu^-$ decay is reported with high significance using proton-proton collision data, corresponding to an integrated luminosity of $5.4\,fb^{-1}$, collected with the LHCb detector at a centre-of-mass energy of 13 TeV. A yield of $279 \pm 19 $ $\Sigma^+ \to p \mu^+ \mu^-$ decays is observed. [...]
LHCb-CONF-2024-002; CERN-LHCb-CONF-2024-002.- Geneva : CERN, 2024 - 16. Fulltext: LHCb-CONF-2024-002 - PDF; LHCb-CONF-2024-002-figures - ZIP;
In : The XV International Conference on Beauty, Charm, Hyperons in Hadronic Interactions (BEACH 2024) , Charleston, Sc, Us, 3 - 7 Jun 2024

Record dettagliato
2024-04-02
18:14
Observation of the rare decay $J\mskip -3mu/\mskip -2mu\psi \to \mu^+\mu^-\mu^+\mu^-$ /LHCb Collaboration
The rare electromagnetic decay $J\mskip -3mu/\mskip -2mu\psi \to \mu^+\mu^-\mu^+\mu^-$ is observed with significance greatly exceeding the discovery threshold, using the proton-proton collision data collected by the LHCb experiment in 2016-2018 at a center-of-mass energy of 13 $\textrm{TeV}$, corresponding to an integrated luminosity of 5.4 $\text{fb}^{-1}$. The rate of this decay is measured relative to that of $J\mskip -3mu/\mskip -2mu\psi \to \mu^+\mu^-$ mode. [...]
LHCb-CONF-2024-001; CERN-LHCb-CONF-2024-001.- Geneva : CERN, 2024 - 17. Fulltext: LHCb-CONF-2024-001 - PDF; LHCb-CONF-2024-001_Figures - ZIP;
In : 58th Rencontres de Moriond on QCD and High Energy Interactions, La Thuile, Italy, 31 Mar - 7 Apr 2024

Record dettagliato
2023-10-24
09:25
Pending /LHCb Collaboration
Pending
LHCb-CONF-2023-005; CERN-LHCb-CONF-2023-005.- Geneva : CERN, 2023 - 23.
In : 12th International Workshop on the CKM Unitarity Triangle (CKM 2023), Santiago De Compostela, Spain, 18 - 22 Sep 2023

Record dettagliato
2023-10-04
14:36
Measurement of $CP$ asymmetry in $B^0_s \rightarrow D^{\mp}_s K^{\pm}$ decays /LHCb Collaboration
A measurement of the $CP$-violating parameters in $B^0_s \rightarrow > D^{\mp}_s K^{\pm}$ decays obtained from $pp$ collisions is reported, using a data set corresponding to an integrated luminosity of $6\,\textrm{fb}^{-1}$ at a centre-of-mass energy of ${\sqrt{s}=13 \,\textrm{TeV}}$ recorded with the LHCb detector between 2015 and 2018. The measured values are: > \begin{align*} C_f &= \phantom{+}0.791 \pm 0.061 \pm 0.022 \, , \\ A_f^{\Delta \Gamma} &= -0.051 \pm 0.134 \pm 0.037\, , \\ A_{\bar{f}}^{\Delta \Gamma} &= -0.303 \pm 0.125 \pm 0.036\, , \\ S_f &= -0.571 \pm 0.084 \pm 0.023\, , \\ S_{\bar{f}} &= -0.503 \pm 0.084 \pm 0.025 \, , \end{align*} where the uncertainties are statistical and systematic, respectively. [...]
LHCb-CONF-2023-004; CERN-LHCb-CONF-2023-004.- Geneva : CERN, 2023 - 25. Fulltext: LHCb-CONF-2023-004-Fig-Supplementary - ZIP; LHCb-CONF-2023-004 - PDF; LHCb-CONF-2023-004_final_typofix - PDF; LHCb-CONF-2023-004-Fig - ZIP;
In : 12th International Workshop on the CKM Unitarity Triangle (CKM 2023), Santiago De Compostela, Spain, 18 - 22 Sep 2023

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