Multidifferential study of identified charged hadron distributions in ZZ-tagged jets in proton-proton collisions at s=\sqrt{s}=13 TeV

Jet fragmentation functions are measured for the first time in proton-proton collisions for charged pions, kaons, and protons within jets recoiling against a $Z$ boson. The charged-hadron distributions are studied longitudinally and transversely to the jet direction for jets with transverse momentum 20 $< p_{\textrm{T}} < 100$ GeV and in the pseudorapidity range $2.5 < \eta < 4$. The data sample was collected with the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.64 fb$^{-1}$. Triple differential distributions as a function of the hadron longitudinal momentum fraction, hadron transverse momentum, and jet transverse momentum are also measured for the first time. This helps constrain transverse-momentum-dependent fragmentation functions. Differences in the shapes and magnitudes of the measured distributions for the different hadron species provide insights into the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb public pages

Study of the B−→Λc+Λˉc−K−B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-} decay

The decay $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ is studied in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV using data corresponding to an integrated luminosity of 5 $\mathrm{fb}^{-1}$ collected by the LHCb experiment. In the $\Lambda_{c}^+ K^{-}$ system, the $\Xi_{c}(2930)^{0}$ state observed at the BaBar and Belle experiments is resolved into two narrower states, $\Xi_{c}(2923)^{0}$ and $\Xi_{c}(2939)^{0}$, whose masses and widths are measured to be $$m(\Xi_{c}(2923)^{0}) = 2924.5 \pm 0.4 \pm 1.1 \,\mathrm{MeV}, \\ m(\Xi_{c}(2939)^{0}) = 2938.5 \pm 0.9 \pm 2.3 \,\mathrm{MeV}, \\ \Gamma(\Xi_{c}(2923)^{0}) = \phantom{000}4.8 \pm 0.9 \pm 1.5 \,\mathrm{MeV},\\ \Gamma(\Xi_{c}(2939)^{0}) = \phantom{00}11.0 \pm 1.9 \pm 7.5 \,\mathrm{MeV},$$ where the first uncertainties are statistical and the second systematic. The results are consistent with a previous LHCb measurement using a prompt $\Lambda_{c}^{+} K^{-}$ sample. Evidence of a new $\Xi_{c}(2880)^{0}$ state is found with a local significance of $3.8\,\sigma$, whose mass and width are measured to be $2881.8 \pm 3.1 \pm 8.5\,\mathrm{MeV}$ and $12.4 \pm 5.3 \pm 5.8 \,\mathrm{MeV}$, respectively. In addition, evidence of a new decay mode $\Xi_{c}(2790)^{0} \to \Lambda_{c}^{+} K^{-}$ is found with a significance of $3.7\,\sigma$. The relative branching fraction of $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ with respect to the $B^{-} \to D^{+} D^{-} K^{-}$ decay is measured to be $2.36 \pm 0.11 \pm 0.22 \pm 0.25$, where the first uncertainty is statistical, the second systematic and the third originates from the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb public pages

Measurement of the ratios of branching fractions R(D∗)\mathcal{R}(D^{*}) and R(D0)\mathcal{R}(D^{0})

The ratios of branching fractions $\mathcal{R}(D^{*})\equiv\mathcal{B}(\bar{B}\to D^{*}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(\bar{B}\to D^{*}\mu^{-}\bar{\nu}_{\mu})$ and $\mathcal{R}(D^{0})\equiv\mathcal{B}(B^{-}\to D^{0}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(B^{-}\to D^{0}\mu^{-}\bar{\nu}_{\mu})$ are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0 fb${ }^{-1}$ of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode $\tau^{-}\to\mu^{-}\nu_{\tau}\bar{\nu}_{\mu}$. The measured values are $\mathcal{R}(D^{*})=0.281\pm0.018\pm0.024$ and $\mathcal{R}(D^{0})=0.441\pm0.060\pm0.066$, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is $\rho=-0.43$. Results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-039.html (LHCb public pages

Vegetative propagation of vinhático (Plathymenia foliolosa Benth) for mini-cuttings

Este trabalho teve como objetivo geral o estudo da propagação vegetativa do vinhático (Plathymenia foliolosa) via miniestaquia e como objetivos específicos avaliar: 1) a germinação das sementes de seis progênies de vinhático (Plathymenia foliolosa); 2) a produção de brotações e a sobrevivência de minicepas em minijardim clonal; 3) o efeito da redução foliar das miniestacas no enraizamento e crescimento das mudas de progênies de vinhático (Plathymenia foliolosa) via miniestaquia; e 4) a influência do tipo de miniestaca e do efeito de dosagens de AIB no enraizamento de vinhático (Plathymenia foliolosa). Foram utilizadas como minicepas mudas originadas de propagação via seminífera, utilizando sementes de seis progênies de vinhático (Plathymenia foliolosa Benth), oriundas dos municípios de Laranjal (P01), Reduto (P03), Brás Pires (P19), Porto Firme (P21), Ponte Nova (P45) e Amparo da Serra (P53). As sementes foram pré-tratadas com ácido sulfúrico por 10 minutos e, em seguida, semeadas. Aos 30 dias após a semeadura, foi avaliada a taxa de germinação. O minijardim clonal foi constituído por minicepas em sistema semi-hidropônico, obtidas pela propagação seminífera das seis progênies de vinhático (Plathymenia foliolosa). As mudas foram transplantadas no espaçamento de 10 x 10 cm, contendo um total de 96 minicepas por progênie. A nutrição mineral das minicepas foi feita por fertirrigação por gotejamento aplicada três vezes ao dia, numa vazão total diária de 4 L m -2. Na avaliação da influência da redução foliar no enraizamento de vinhático, foram utilizadas miniestacas da parte apical com altura variando de 8 a 10 cm de comprimento, sendo os tratamentos constituídos por 100% de redução foliar (sem folha), com 75% de redução foliar e sem redução foliar. O enraizamento das miniestacas foi feito utilizando um período de permanência de 60 dias em casa de vegetação climatizada, com a aclimatação em casa de sombra por 15 dias, seguida da transferência para a área de pleno sol, onde se procedeu à avaliação final para as miniestacas, aos 90 dias. Para avaliação da aplicação de AIB nas dosagens 0, 20.000, 40.000 e 60.000 mg L-1 e dos tipos de miniestacas (apical e intermediária), elas permaneceram 100 dias na casa de vegetação. As progênies P19 e P03 apresentaram as maiores taxas de germinação (88,3% e 87,7%, respectivamente) e as progênies P01 (54,8%) e P45 (47,7%), os menores valores. Quanto à sobrevivência das minicepas em minijardim clonal, após a quarta coleta sucessiva de miniestacas, as progênies P3 e P19 apresentaram os maiores percentuais de sobrevivência (64,5% e 61,5%, respectivamente), enquanto as progênies P1 (32,3%) e P45 (25%), os menores valores observados quanto a essa avaliação. O número médio de miniestacas/minicepa/coleta produzidas variou de 0,8 (progênie 53) a 4,8 (progênie 01), sendo a produtividade média das minicepas/m2 de 120 miniestacas por coleta. Quanto à influência da redução foliar das miniestacas no enraizamento adventício, os tratamentos sem redução foliar e com 75% de redução não apresentaram diferenças significativas entre si, no entanto, foi observada 100% de mortalidade das miniestacas quando feita a redução total da folhas. Com base nos resultados, pode-se concluir que as progênies apresentaram heterogeneidade na taxa de germinação e respostas diferenciadas quanto ao potencial produtivo das minicepas nas coletas sucessivas de miniestacas, que a manutenção das folhas é importante para o enraizamento e a sobrevivência de miniestacas, destacando-se a não redução foliar das miniestacas, devido, principalmente, à praticidade operacional e à otimização no tempo. A sobrevivência das miniestacas foi influenciada pelo tipo de miniestaca e pela aplicação do AIB.This work had as main objective the study of vegetative propagation via mini-cutting vinhático and specific objectives: 1) evaluate the germination of six progenies of Plathymenia foliolosa; 2) Evaluate the production and survival of the mini-stumps in mini-clonal hedge; 3) evaluate the effect of reduction of leaves of mini-cuttings on rooting and seedling growth of progenies of Plathymenia foliolosa by mini-cutting; and 4) evaluate the type influence of mini-cuttings and the effects of doses of IBA on rooting Plathymenia foliolosa. Plants originated from the propagation of seminiferous were used as mini-stumps and six seed progenies of vinhático (Plathymenia foliolosa Benth) collected from Laranjal (P01), Reduto (P03), Braz Pires (P19), Porto Firme (P21), Ponte Nova (P45) and Amparo do Serra (P53) municipalities were used. The seeds were pre-treated with sulfuric acid for 10 minutes and then taken to germinate. At 30 days after germination, the germination rate was evaluated. The clonal mini-hedges consisted of mini-stumps in semi-hydroponic system, obtained by seminiferous propagation from six progenies of Plathymenia foliolosa. The seedlings were transplanted at a spacing of 10 x 10 cm, containing a total of 96 mini-stumps per progeny. The mineral nutrition of mini-stumps consisted of drip fertirrigation applied three times daily at a total daily flow rate of 4 L m -2. Mini-cuttings form apical part were used to evaluate the influence of leaf reduction on rooting of vinhático with 10 cm long, with treatments consisting of 100% reduction of leaf (without leaf), with 75% reduction of leaf and treatment without leaf reduction. The rooting of the shoots was performed using a remaining term of the plant material in the acclimatized greenhouse for 60 days, with acclimation in shade house for 15 days, followed by transfer to the area of full sun, where it was made a final assessment for the cuttings at 90 days. To evaluate the application of IBA at doses (0, 20.000, 40.000 and 60.000 mg L-1) and types of mini-cuttings (apical and intermediate), the cuttings remained 100 days in the greenhouse. The P19 and P03 progenies had the highest germination rates (88,3 % and 87,7 %, respectively) and P01 (54,8 %) and P45 progeny (47,7%) had the lowest values obtained. As for the survival of mini-stumps in clonal mini- hedges after the fourth successive cuttings collection, P3 and P19 progenies showed the highest survival percentages (64,5 % and 61,5%, respectively), while progeny P1 (32,3 %) and P45 (25%) showed the lowest values observed for this evaluation. The average number of mini-cuttings/mini-stump/collection produced ranged from 0.83 (progeny 53) to 4.8 (progeny 01), and the average productivity of 120 m2 mini-stumps mini-cuttings per collection. As for the influence of reduction of leaves of adventitious rooting in mini-cuttings, foliar treatments without reduction and 75% reduction showed no significant differences, however, 100% mortality was observed when the mini-cuttings had total reduction in leaves. Based on the results, it can be concluded that: progeny showed heterogeneity in the rate of germination; Progenies showed different responses to the productive potential of mini-stumps in successive collections of cuttings. The maintenance of the leaves is important for the survival and rooting of mini-cuttings, especially the reduction of non-leaf mini-cuttings, mainly due to the operational usability and optimization time. The survival of the mini- cuttings was influenced by its type and by the implementation of AIB.Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Production of mini-cuttings and the influence of leaf reduction on rooting of vinhático (Plathymenia foliolosa benth.)

The objective of this work was to evaluate the production and survival of the mini-stumps in mini-clonal hedge and the effect of leaf reduction of mini-cuttings on rooting and seedling growth of progenies of Vinhático (Plathymenia foliolosa) by mini-cutting. Apical mini-cuttings were used to evaluate the influence of leaf reduction on the rooting of vinhático; the mini-cuttings ranged between 8 to 10 cm in length and samples were subjected to100% leaf reduction (without leaf), 75% of leaf reduction, or no leaf reduction. As for the survival of mini-stumps in mini-clonal hedge, after the fourth successive mini-cuttings collection, P3 and P19 progenies showed the highest survival percentages (64.5% and 61.5%, respectively), while progenies P1 (32.3 %) and P45 (25%) showed the lowest values for this parameter. The average number of mini-cuttings/mini-stump/collection produced ranged from 0.83 (progeny 53) to 4.8 (progeny 01) and the average productivity was 120 m2 mini-stumps/mini-cuttings per collection. These results suggest that leaf reduction in adventitious rooting in mini-cuttings did not result in any difference between foliar treatments without reduction and 75% leaf reduction; however, 100% mortality was observed when the mini-cuttings were made with total leaf reduction.The progenies studied showed potential regeneration of mini-stumps, thus allowing the realization of successive collections of young shoots.Objetivou-se com o presente estudo avaliar a produção e sobrevivência de minicepas em minijardim clonal e o efeito da redução foliar das miniestacas no enraizamento e crescimento das mudas de progênies de vinhático (Plathymenia foliolosa) via miniestaquia. Foram utilizadas miniestacas da parte apical com altura variando de 8 a 10 cm de comprimento, sendo os tratamentos constituídos por 100% de redução foliar (sem folha), com 75% de redução foliar e sem redução foliar. Quanto à sobrevivência das minicepas em minijardim clonal, após a quarta coleta sucessiva de miniestacas, as progênies P3 e P19 apresentaram os maiores percentuais de sobrevivência (64,5% e 61,5%, respectivamente), enquanto as progênies P1 (32,3%) e P45 (25%), os menores valores observados quanto a essa avaliação. O número médio de miniestacas/minicepa/coleta produzidas variou de 0,8 (progênie 53) a 4,8 (progênie 01), sendo a produtividade média das minicepas/m2 de 120 miniestacas por coleta. Com base nos resultados obtidos, concluiu-se que há influência da redução foliar das miniestacas no enraizamento adventício, que os tratamentos sem redução foliar e com 75% de redução não apresentaram diferenças significativas, no entanto, foi observado 100% de mortalidade das miniestacas quando feita a redução total das folhas. Concluiu-se também que as progênies estudadas apresentaram potencial quanto à regeneração das minicepas, permitindo, assim, a realização de coletas sucessivas de brotações juvenis

Search for the rare hadronic decay Bs0→ppˉB_s^0\to p \bar{p}

A search for the rare hadronic decay Bs0→pp¯ is performed using proton-proton collision data recorded by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6  fb-1. No evidence of the decay is found and an upper limit on its branching fraction is set at B(Bs0→pp¯)&lt;4.4(5.1)×10-9 at 90% (95%) confidence level; this is currently the world’s best upper limit. The decay mode B0→pp¯ is measured with very large significance, confirming the first observation by the LHCb experiment in 2017. The branching fraction is determined to be B(B0→pp¯)=(1.27±0.15±0.05±0.04)×10-8, where the first uncertainty is statistical, the second is systematic and the third is due to the external branching fraction of the normalization channel B0→K+π-. The combination of the two LHCb measurements of the B0→pp¯ branching fraction yields B(B0→pp¯)=(1.27±0.13±0.05±0.03)×10-8.A search for the rare hadronic decay $B_s^0\to p \bar{p}$ is performed using proton-proton collision data recorded by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb$^{-1}$. No evidence of the decay is found and an upper limit on its branching fraction is set at ${\cal B}(B_s^0\to p \bar{p}) < 4.4~(5.1) \times 10^{-9}$ at 90% (95%) confidence level; this is currently the world's best upper limit. The decay mode $B^0\to p \bar{p}$ is measured with very large significance, confirming the first observation by the LHCb experiment in 2017. The branching fraction is determined to be ${\cal B}(B^0\to p \bar{p}) = \rm (1.27 \pm 0.15 \pm 0.05 \pm 0.04) \times 10^{-8}$, where the first uncertainty is statistical, the second is systematic and the third is due to the external branching fraction of the normalization channel $B^0\to K^+\pi^-$. The combination of the two LHCb measurements of the $B^0\to p \bar{p}$ branching fraction yields ${\cal B}(B^0\to p \bar{p}) = \rm (1.27 \pm 0.13 \pm 0.05 \pm 0.03) \times 10^{-8}$

Measurement of the prompt D0D^0 nuclear modification factor in ppPb collisions at sNN=8.16\sqrt{s_\mathrm{NN}} = 8.16 TeV

International audienceThe production of prompt $D^0$ mesons in proton-lead collisions in the forward and backward configurations at a center-of-mass energy per nucleon pair of $\sqrt{s_\mathrm{NN}} = 8.16~\mathrm{TeV}$ is measured by the LHCb experiment. The nuclear modification factor of prompt $D^0$ mesons is determined as a function of the transverse momentum $p_\mathrm{T}$, and rapidity in the nucleon-nucleon center-of-mass frame $y^*$. In the forward rapidity region, significantly suppressed production with respect to $pp$ collisions is measured, which provides significant constraints of nuclear parton distributions and hadron production down to the very low Bjorken-$x$ region of $\sim 10^{-5}$. In the backward rapidity region, a suppression with a significance of 2.0 - 3.8 standard deviations compared to nPDF expectations is found in the kinematic region of $p_\mathrm{T}>6~\mathrm{GeV}/c$ and $-3.25<y^*<-2.5$, corresponding to $x\sim 0.01$

Amplitude analysis of the Λc+→pK−π+\Lambda^+_c\to pK^-\pi^+ decay and Λc+\Lambda^+_c baryon polarization measurement in semileptonic beauty hadron decays

An amplitude analysis of $\Lambda^+_c \to pK^-\pi^+$ decays together with a measurement of the $\Lambda^+_c$ polarization vector in semileptonic beauty hadron decays is presented. A sample of $400\,000$ candidates is selected from proton-proton collisions recorded by the LHCb detector at a center-of-mass energy of 13 TeV. An amplitude model is developed and the resonance fractions as well as two- and three-body decay parameters are reported. The mass and width of the $\Lambda(2000)$ state are also determined. A significant $\Lambda^+_c$ polarization is found. A large sensitivity of the $\Lambda^+_c \to pK^-\pi^+$ decay to the polarization is seen, making the amplitude model suitable for $\Lambda^+_c$ polarization measurements in other systems.An amplitude analysis of Λc+→pK-π+ decays together with a measurement of the Λc+ polarization vector in semiōleptonic beauty hadron decays is presented. A sample of 400 000 candidates is selected from proton-proton collisions recorded by the LHCb detector at a center-of-mass energy of 13 TeV. An amplitude model is developed and the resonance fractions as well as two- and three-body decay parameters are reported. The mass and width of the Λ(2000) state are also determined. A significant Λc+ polarization is found. A large sensitivity of the Λc+→pK-π+ decay to the polarization is seen, making the amplitude model suitable for Λc+ polarization measurements in other systems.An amplitude analysis of $\Lambda^+_c \to pK^-\pi^+$ decays together with a measurement of the $\Lambda^+_c$ polarization vector in semileptonic beauty hadron decays is presented. A sample of $400\,000$ candidates is selected from proton-proton collisions recorded by the LHCb detector at a center-of-mass energy of 13 TeV. An amplitude model is developed and the resonance fractions as well as two- and three-body decay parameters are reported. The mass and width of the $\Lambda(2000)$ state are also determined. A significant $\Lambda^+_c$ polarization is found. A large sensitivity of the $\Lambda^+_c \to pK^-\pi^+$ decay to the polarization is seen, making the amplitude model suitable for $\Lambda^+_c$ polarization measurements in other systems

Measurement of the prompt D0D^0 nuclear modification factor in ppPb collisions at sNN=8.16\sqrt{s_\mathrm{NN}} = 8.16 TeV

International audienceThe production of prompt $D^0$ mesons in proton-lead collisions in the forward and backward configurations at a center-of-mass energy per nucleon pair of $\sqrt{s_\mathrm{NN}} = 8.16~\mathrm{TeV}$ is measured by the LHCb experiment. The nuclear modification factor of prompt $D^0$ mesons is determined as a function of the transverse momentum $p_\mathrm{T}$, and rapidity in the nucleon-nucleon center-of-mass frame $y^*$. In the forward rapidity region, significantly suppressed production with respect to $pp$ collisions is measured, which provides significant constraints of nuclear parton distributions and hadron production down to the very low Bjorken-$x$ region of $\sim 10^{-5}$. In the backward rapidity region, a suppression with a significance of 2.0 - 3.8 standard deviations compared to nPDF expectations is found in the kinematic region of $p_\mathrm{T}>6~\mathrm{GeV}/c$ and $-3.25<y^*<-2.5$, corresponding to $x\sim 0.01$