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EP Articles

Darreres entrades:
2024-08-12
13:51
Observation of muonic Dalitz decays of $\chi_b$ mesons and precise spectroscopy of hidden-beauty states / LHCb Collaboration
The decays of the $\chi_{b1}(1P)$, $\chi_{b2}(1P)$, $\chi_{b1}(2P)$ and $\chi_{b2}(2P)$ mesons into the $\Upsilon(1S)\mu^+\mu^-$ final state are observed with a high significance using proton-proton collision data collected with the LHCb detector and corresponding to an integrated luminosity of 9fb$^{-1}$. The newly observed decays together with the $\Upsilon(2S)\rightarrow \Upsilon(1S)\pi^+\pi^-$ and $\Upsilon(3S)\rightarrow \Upsilon(2S)\pi^+\pi^-$ decay modes are used for precision measurements of the mass and mass splittings for the hidden-beauty states..
arXiv:2408.05134; LHCb-PAPER-2024-025,CERN-EP-2024-207; LHCb-PAPER-2024-025; CERN-EP-2024-207; LHCB-PAPER-2024-025.- Geneva : CERN, 2024-10 - 29 p. - Published in : JHEP 2410 (2024) 122 Fulltext: PDF; Related data file(s): ZIP;

Registre complet - Registres semblants
2024-07-19
16:36
Search for the rare decay of charmed baryon <math display="inline"><msubsup><mi mathvariant="normal">Λ</mi><mi>c</mi><mo>+</mo></msubsup></math> into the <math display="inline"><mi>p</mi><msup><mi>μ</mi><mo>+</mo></msup><msup><mi>μ</mi><mo>-</mo></msup></math> final state / LHCb Collaboration
A search for the nonresonant $\Lambda_c^+ \to p \mu^+ \mu^-$ decay is performed using proton-proton collision data recorded at a centre-of-mass energy of 13 TeV by the LHCb experiment, corresponding to an integrated luminosity of 5.4 fb$^{-1}$. No evidence for the decay is found in the dimuon invariant-mass regions where the expected contributions of resonances is subdominant. [...]
arXiv:2407.11474; LHCb-PAPER-2024-005; CERN-EP-2024-158; LHCB-PAPER-2024-005.- Geneva : CERN, 2024-09-01 - 13 p. - Published in : Phys. Rev. D 110 (2024) 052007 Fulltext: LHCb-PAPER-2024-005 - PDF; 2407.11474 - PDF; Publication - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

Registre complet - Registres semblants
2024-06-20
09:49
Precision measurement of the $\Xi_b^-$ baryon lifetime / LHCb Collaboration
A sample of $pp$ collision data, corresponding to an integrated luminosity of 5.5 fb$^{-1}$ and collected by the LHCb experiment during Run 2, is used to measure the ratio of the lifetime of the $\Xi^-_b$ baryon to that of the $\Lambda^0_b$ baryon, $r_{\tau}\equiv\tau_{\Xi^-_b}/\tau_{\Lambda^0_b}$. The value ${r_{\tau}^{\rm Run\,2}=1.076\pm0.013\pm0.006}$ is obtained, where the first uncertainty is statistical and the second systematic. [...]
arXiv:2406.12111; LHCb-PAPER-2024-010; CERN-EP-2024-139.- Geneva : CERN, 2024-10-01 - 16 p. - Published in : Phys. Rev. D 110 (2024) 072002 Fulltext: 2406.12111 - PDF; Publication - PDF; Xibm_Lifetime_Run2_Paper - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

Registre complet - Registres semblants
2024-06-10
11:50
Comprehensive analysis of local and nonlocal amplitudes in the $B^0 \to K^{*0} \mu^+\mu^-$ decay / LHCb Collaboration
A comprehensive study of the local and nonlocal amplitudes contributing to the decay $B^0\rightarrow K^{*0}(\to K^+\pi^-) \mu^+\mu^-$ is performed by analysing the phase-space distribution of the decay products. The analysis is based on $pp$ collision data corresponding to an integrated luminosity of 8.4fb$^{-1}$ collected by the LHCb experiment. [...]
arXiv:2405.17347; LHCb-PAPER-2024-011; CERN-EP-2024-122; LHCB-PAPER-2024-011.- Geneva : CERN, 2024-09-05 - 60 p.
Fulltext: document - PDF; LHCb-PAPER-2024-011 - PDF; 2405.17347 - PDF; Related data file(s): ZIP;

Registre complet - Registres semblants
2024-06-05
16:14
Observation of New Charmonium or Charmoniumlike States in <math display="inline"><msup><mi>B</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>D</mi><mrow><mo>*</mo><mo>±</mo></mrow></msup><msup><mi>D</mi><mo>∓</mo></msup><msup><mi>K</mi><mo>+</mo></msup></math> Decays / LHCb Collaboration
A study of resonant structures in $B^{+}\rightarrow{D^{*+}D^{-}K^{+}}$ and $B^{+}\rightarrow{D^{*-}D^{+}K^{+}}$ decays is performed, using proton-proton collision data at centre-of-mass energies of $\sqrt{s}=7, 8$, and $13$TeV recorded by the LHCb experiment, corresponding to an integrated luminosity of 9 fb${}^{-1}$. A simultaneous amplitude fit is performed to the two channels with contributions from resonances decaying to $D^{*-}D^{+}$ and $D^{*+}D^{-}$ states linked by $C$-parity. [...]
arXiv:2406.03156; LHCb-PAPER-2023-047; CERN-EP-2024-096.- Geneva : CERN, 2024-09-27 - 14 p. - Published in : Phys. Rev. Lett. 133 (2024) 131902 Fulltext: LHCb-PAPER-2023-047_arxiv - PDF; 2406.03156 - PDF; Publication - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

Registre complet - Registres semblants
2024-06-03
10:41
Amplitude analysis of the radiative decay $B^0_s\to K^+K^-\gamma$ / LHCb Collaboration
A search for radiative decay of $B^0_s$ mesons to orbitally excited $K^+K^-$ states is performed using proton proton collisions recorded by the \mbox{LHCb}\xspace experiment, corresponding to an integrated luminosity of 9 fb$^{-1}$. The dikaon spectrum in the mass range $m_{KK}<2400\ \text{MeV/}c^2$ is dominated by the $\phi(1020)$ resonance that accounts for almost 70$\%$ of the decay rate. [...]
arXiv:2406.00235; LHCb-PAPER-2024-002; CERN-EP-2024-115; LHCB-PAPER-2024-002.- Geneva : CERN, 2024-08-13 - 39 p. - Published in : 10.1007/JHEP08(2024)093 Fulltext: 2406.00235 - PDF; document - PDF; LHCb-PAPER-2024-002_arxiv - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

Registre complet - Registres semblants
2024-05-22
12:15
Study of $b-$hadron decays to $\Lambda_c^+h^-h^{\prime -}$ final states / LHCb Collaboration
Decays of $\Xi_{b}^{-}$ and $\Omega_{b}^{-}$ baryons to $\Lambda_{c}^{+} h^- h^{\prime -}$ final states, with $h^- h^{\prime -}$ being $\pi^{-}\pi^{-}$, $K^{-}\pi^{-}$ and $K^{-}K^{-}$ meson pairs, are searched for using data collected with the LHCb detector. The data sample studied corresponds to an integrated luminosity of $8.7 \rm fb^{-1}$ of $pp$ collisions collected at centre-of-mass energies $\sqrt{s} = 7$, $8$ and $13 \rm TeV$. [...]
arXiv:2405.12688; CERN-EP-2024-116; LHCb-PAPER-2024-013; LHCB-PAPER-2024-013.- Geneva : CERN, 2024-08 - 32 p. - Published in : JHEP 2408 (2024) 132 Fulltext: 2405.12688 - PDF; document - PDF; LHCb-PAPER-2024-013 - PDF; Related data file(s): ZIP;

Registre complet - Registres semblants
2024-05-22
10:23
Search for the lepton-flavor violating decay $B_s^0\to \phi \mu^\pm \tau^\mp$ / LHCb Collaboration
A search for the lepton-flavor violating decays $B^0_s\to\phi\mu^\pm\tau^\mp$ is presented, using a sample of proton-proton collisions at center-of-mass energies of 7, 8, and 13 TeV, collected with the LHCb detector and corresponding to a total integrated luminosity of $9\,\text{fb}^{-1}$. The $\tau$ leptons are selected using decays with three charged pions. [...]
arXiv:2405.13103; LHCb-PAPER-2024-006; CERN-EP-2024-114.- Geneva : CERN, 2024-10-01 - 12 p. - Published in : Phys. Rev. D 110 (2024) 072014 Fulltext: 2405.13103 - PDF; Publication - PDF; Related data file(s): ZIP;

Registre complet - Registres semblants
2024-05-21
17:12
Transverse polarization measurement of Λ hyperons in pNe collisions at $ \sqrt{{\textrm{s}}_{\textrm{NN}}} $ = 68.4 GeV with the LHCb detector / LHCb Collaboration
A measurement of the transverse polarization of the $\Lambda$ and $\bar{\Lambda}$hyperons in $p$Ne fixed-target collisions at $\sqrt{s_{NN}}$=68.4 GeV is presented using data collected by the LHCb detector. The polarization is studied using the decay $\Lambda \rightarrow p \pi^-$ together with its charge conjugated process, the integrated values measured are $$ P_{\Lambda} = 0.029 \pm 0.019 \, (\rm{stat}) \pm 0.012 \, (\rm{syst}) \, , $$ $$ P_{\bar{\Lambda}} = 0.003 \pm 0.023 \, (\rm{stat}) \pm 0.014 \,(\rm{syst}) \, $$ Furthermore, the results are shown as a function of the Feynman $x$ variable, transverse momentum, pseudorapidity and rapidity of the hyperons, and are compared with previous measurements..
arXiv:2405.11324; CERN-EP-2024-121; LHCb-PAPER-2024-009.- Geneva : CERN, 2024-09-17 - 18 p. - Published in : JHEP 2409 (2024) 082 Fulltext: 2405.11324 - PDF; document - PDF; LHCb-PAPER-2024-009 - PDF; Related data file(s): ZIP;

Registre complet - Registres semblants
2024-05-13
11:52
Search for Time-Dependent <math display="inline"><mi>C</mi><mi>P</mi></math> Violation in <math display="inline"><mrow><msup><mrow><mi>D</mi></mrow><mrow><mn>0</mn></mrow></msup><mo stretchy="false">→</mo><msup><mrow><mi>π</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mo>-</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mn>0</mn></mrow></msup></mrow></math> Decays / LHCb Collaboration
A measurement of time-dependent $CP$ violation in $D^0 \rightarrow \pi^+ \pi^- \pi^0$ decays using a $pp$ collision data sample collected by the LHCb experiment in 2012 and from 2015 to 2018, corresponding to an integrated luminosity of 7.7$\,\mathrm{fb}^{-1}$, is presented. The initial flavour of each $D^0$ candidate is determined from the charge of the pion produced in the $D^*(2010)^+ \rightarrow D^0 \pi^+$ decay. [...]
arXiv:2405.06556; LHCb-PAPER-2024-003; CERN-EP-2024-111; LHCB-PAPER-2024-003.- Geneva : CERN, 2024-09-05 - 12 p. - Published in : Phys. Rev. Lett. 133 (2024) 101803 Fulltext: LHCb-PAPER-2024-003 - PDF; 2405.06556 - PDF; Publication - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

Registre complet - Registres semblants