# EP Articles

Πρόσφατες προσθήκες:
2020-12-10
11:44
 First observation of the decay $B_s^0 \to K^-\mu^+\nu_\mu$ and measurement of $|V_{ub}|/|V_{cb}|$ / LHCb Collaboration The first observation of the suppressed semileptonic $B_s^0 \to K^-\mu^+\nu_\mu$ decay is reported. Using a data sample recorded in $pp$ collisions in 2012 with the LHCb detector, corresponding to an integrated luminosity of 2 $\mathrm{fb}^{-1}$, the branching fraction $\mathcal{B}(B_s^0 \to K^-\mu^+\nu_\mu)$} is measured to be $(1.06\pm0.05~(\mathrm{stat})\pm0.08~(\mathrm{syst}))\times 10^{-4}$, where the first uncertainty is statistical and the second one represents the combined systematic uncertainties. [...] arXiv:2012.05143; LHCb-PAPER-2020-038; CERN-EP-2020-224; LHCB-PAPER-2020-038.- Geneva : CERN, 2021-02-25 - 11 p. - Published in : Phys. Rev. Lett. 126 (2021) 081804 Article from SCOAP3: PDF; Fulltext: LHCb-PAPER-2020-038 - PDF; 2012.05143 - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

2020-12-08
11:53
 Amplitude analysis of the $B^+ \to D^+ D^- K^+$ decay / LHCb Collaboration Results are reported from an amplitude analysis of the $B^+\to D^+D^-K^+$ decay. The analysis is carried out using LHCb proton-proton collision data taken at $\sqrt{s}=7,8,$ and $13$ TeV, corresponding to a total integrated luminosity of 9 fb$^{-1}$. [...] arXiv:2009.00026; LHCb-PAPER-2020-025; CERN-EP-2020-159.- 2020-12-07 - 48 p. - Published in : Phys. Rev. D 102 (2020) 112003 Article from SCOAP3: PDF; Fulltext: main_PRD - PDF; 2009.00026 - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

2020-11-23
08:58
 Stochastic cooling pickup/kicker developments for the High-precision Spectrometer Ring in the HIAF Project at IMP / Zhu, Guangyu (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) ; Wu, Junxia (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) ; Caspers, Fritz (CERN) ; Du, Ze (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) ; Wei, Yuan (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) ; Yang, Jiancheng (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) ; Hu, Xuejing (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) ; Zhang, Yong (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) ; Xie, Hongming (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) ; Jing, Long (Lanzhou, Inst. Modern Phys. ; Beijing, GUCAS) et al. Stochastic cooling of the Spectrometer Ring (SRing) at the High Intensity heavy-ion Accelerator Facility (HIAF) project in China, which is used mainly for experiments with radioactive fragment beams, is applied to speed up the cooling process of a stored ion beam. In this study, both a Faltin traveling wave structure and a novel slot-ring standing wave structure based on a ceramic vacuum chamber are discussed and evaluated for the pickup/kicker of the SRing stochastic cooling system. [...] CERN-OPEN-2020-014.- 2021 - 12 p. - Published in : IEEE Trans. Nucl. Sci. 68 (2020) 9-20 Fulltext from publisher: PDF;

2020-11-18
11:57
 Theoretical and experimental status of rare charm decays / Gisbert, Hector (Dortmund U.) ; Golz, Marcel (Dortmund U.) ; Mitzel, Dominik Stefan (CERN) Rare charm decays offer the unique possibility to explore flavour-changing neutral-currents in the up-sector within the Standard Model and beyond. Due to the lack of effective methods to reliably describe its low energy dynamics, rare charm decays have been considered as less promising for long. [...] arXiv:2011.09478; DO-TH 20/13; CERN-OPEN-2020-012.- Geneva : CERN, 2021-01-27 - 35 p. - Published in : Mod. Phys. Lett. A 36 (2021) 2130002 Fulltext: fulltext1831374 - PDF; 2011.09478 - PDF; Preprint: PDF;

2020-11-05
15:52
 Study of $B_s^0 \to J/\psi \pi^+ \pi^- K^+ K^-$ decays / LHCb Collaboration The decays $B^0_s \rightarrow J/\psi \pi^+\pi^- K^+ K^-$ are studied using a data set corresponding to an integrated luminosity of 9 fb$^{-1}$, collected with the LHCb detector in proton-proton collisions at centre-of-mass energies of 7, 8 and 13 TeV. The decays $B^0_s \rightarrow J/\psi K^{\ast0} \bar{K}^{\ast0}$ and $B^0_s \rightarrow \chi_{c1}(3872)K^+K^-$, where the $K^+K^-$ pair does not originate from a $\phi$ meson, are observed for the first time [...] arXiv:2011.01867; LHCb-PAPER-2020-35; CERN-EP-2020-192; LHCB-PAPER-2020-035.- Geneva : CERN, 2021-02-02 - 34 p. - Published in : JHEP 2102 (2021) 024 Article from SCOAP3: PDF; Fulltext: 2011.01867 - PDF; LHCb-PAPER-2020-035 - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

2020-10-28
10:53
 Observation of a new $\Xi_b^0$ state / LHCb Collaboration Using a proton-proton collision data sample collected by the LHCb experiment, corresponding to an integrated luminosity of 8.5~fb$^{-1}$, the observation of a new excited $\Xi_b^0$ resonance decaying to the $\Xi_b^-\pi^+$ final state is presented. The state, referred to as $\Xi_b(6227)^0$, has a measured mass and natural width of $m(\Xi_b(6227)^0) = 6227.1^{\,+1.4}_{\,-1.5}\pm0.5$ MeV, $\Gamma(\Xi_b(6227)^0) = 18.6^{\,+5.0}_{\,-4.1}\pm1.4$ MeV, where the uncertainties are statistical and systematic. [...] arXiv:2010.14485; LHCb-PAPER-2020-032; CERN-EP-2020-190; LHCB-PAPER-2020-032.- Geneva : CERN, 2021-01-07 - 17 p. - Published in : Phys. Rev. D 103 (2021) 012004 Article from SCOAP3: PDF; Fulltext: PDF; Related data file(s): ZIP; Supplementary information: ZIP;

2020-10-23
15:39
 Measurement of the relative branching fractions of $B^+ \to h^+h^{\prime +}h^{\prime -}$ decays / LHCb Collaboration The relative branching fractions of $B^+ \to h^+h^{\prime +}h^{\prime -}$ decays, where $h^{(\prime)}$ is a pion or kaon, are measured. The analysis is performed with a data sample, collected with the LHCb detector, corresponding to an integrated luminosity of $3.0 {\rm fb}^{-1}$ of $pp$ collisions. [...] arXiv:2010.11802; CERN-EP-2020-189; LHCB-PAPER-2020-031.- Geneva : CERN, 2020-12-18 - 19 p. - Published in : Phys. Rev. D 102 (2020) 112010 Article from SCOAP3: PDF; Fulltext: PDF; Related data file(s): ZIP;

2020-10-21
10:46
 Measurement of differential $b\bar{b}$- and $c\bar{c}$-dijet cross-sections in the forward region of $pp$ collisions at $\sqrt{s}=13 ~ \mathrm{TeV}$ / LHCb Collaboration The inclusive $b \bar{b}$- and $c \bar{c}$-dijet production cross-sections in the forward region of $pp$ collisions are measured using a data sample collected with the LHCb detector at a centre-of-mass energy of 13 TeV in 2016. The data sample corresponds to an integrated luminosity of 1.6 fb$^{-1}$. [...] arXiv:2010.09437; LHCb-PAPER-2020-018; CERN-EP-2020-174; LHCB-PAPER-2020-018.- Geneva : CERN, 2021-02-02 - 37 p. - Published in : JHEP 2102 (2021) 023 Article from SCOAP3: PDF; Fulltext: 2010.09437 - PDF; bb_cc_Run2_paper_v11 - PDF; Related data file(s): ZIP;

2020-10-19
16:13
 Measurement of the CKM angle $\gamma$ in $B^\pm\to D K^\pm$ and $B^\pm \to D \pi^\pm$ decays with $D \to K_\mathrm S^0 h^+ h^-$ / LHCb Collaboration A measurement of $CP$-violating observables is performed using the decays ${B^\pm\to D K^\pm}$ and ${B^\pm\to D \pi^\pm}$, where the $D$ meson is reconstructed in one of the self-conjugate three-body final states $K_{\mathrm S}^0\pi^+\pi^-$ and $K_{\mathrm S}^0K^+K^-$ (commonly denoted $K_{\mathrm S}^0 h^+h^-$). The decays are analysed in bins of the $D$-decay phase space, leading to a measurement that is independent of the modelling of the $D$-decay amplitude. [...] arXiv:2010.08483; LHCb-PAPER-2020-019; CERN-EP-2020-175; LHCB-PAPER-2020-019.- Geneva : CERN, 2021-02-19 - 36 p. - Published in : JHEP 2102 (2021) 169 Article from SCOAP3: PDF; Fulltext: 2010.08483 - PDF; LHCb-PAPER-2020-019_arxiv_submission - PDF; Related data files: ZIP; Supplementary information: ZIP;

2020-10-14
10:06
 Strong constraints on the $b \to s\gamma$ photon polarisation from $B^0\to K^{*0} e^+ e^-$ decays / LHCb Collaboration An angular analysis of the $B^0 \to K^{*0} e^+ e^-$ decay is performed using a data sample corresponding to an integrated luminosity of $9~fb^{-1}$ of $pp$ collisions collected with the LHCb experiment. The analysis is conducted in the very low dielectron mass squared ($q^2$) interval between $0.0008$ and $0.257~{\rm GeV}^2$, where the rate is dominated by the $B^0\to K^{*0}\gamma$ transition with a virtual photon [...] arXiv:2010.06011; LHCb-PAPER-2020-020; CERN-EP-2020-176; LHCB-PAPER-2020-020.- Geneva : CERN, 2020-12-11 - 25 p. - Published in : JHEP 2012 (2020) 081 Article from SCOAP3: PDF; Fulltext: LHCb-PAPER-2020-020 - PDF; 2010.06011 - PDF; Related data file(s): ZIP;