11 research outputs found

    Collection and characterization of cassava germplasm in Comoros

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    Open Access ArticleIn Comoros, cassava plays a major food security role, however yields are low as few modern cultivars are grown. Prior to the introduction of new cultivars, and as a germplasm resource for breeders, germplasm collection missions were undertaken in the three largest islands; Ngazidja, Ndzouani and Mwali; and associated farmer knowledge documented. Cassava landraces were collected from 34 farms, and 17 key informant interviews conducted. Stakes of 79 collected landraces were planted for agro-morphological characterization. All landraces were genotyped using DaRTSeq technology and data analysed to identify duplicates. Genetic fingerprints of 46 unique landraces were co-analysed with 402 previously genotyped landraces and improved cultivars from Tanzania. From this set only one match was made with a very old cultivar, Aipin Valenca, from the Northern Zone in Tanzania. According to SNP data, germplasm from the three islands of Comoros were similarly related to one another, and more distantly related to germplasm from Tanzania. They were most closely related to germplasm from the Northern Zone in Tanzania, suggesting a possible historical introduction of germplasm from this area. Lower levels of diversity were observed on these islands, as well as the islands of Pemba and Zanzibar. This implies limited introduction and movement of cassava germplasm into the islands. Introductions of improved germplasm to Comoros is recommended with the simultaneous conservation of collected unique landraces. Two landraces with high market demand and reported tolerance to diseases were identified for further evaluation with a view to multiplication and distribution and incorporation into the breeding program

    Two-particle transverse momentum correlations in pp and p-Pb collisions at LHC energies

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    Two-particle transverse momentum differential correlators, recently measured in Pb-Pb collisions at LHC energies, provide an additional tool to gain insights into particle production mechanisms and infer transport properties, such as the ratio of shear viscosity to entropy density, of the medium created in Pb--Pb collisions. The longitudinal long-range correlations and the large azimuthal anisotropy measured at low transverse momenta in small collision systems, namely pp and p-Pb, at LHC energies resemble manifestations of collective behaviour. This suggests that locally equilibrated matter may be produced in these small collision systems, similar to what is observed in Pb-Pb collisions. In this work, the same two-particle transverse momentum differential correlators are exploited in pp and p-Pb collisions at s=7\sqrt{s} = 7 TeV and sNN=5.02\sqrt{s_{\rm NN}} = 5.02 TeV, respectively, to seek evidence for viscous effects. Specifically, the strength and shape of the correlators are studied as a function of the produced particle multiplicity to identify evidence for longitudinal broadening that might reveal the presence of viscous effects in these smaller systems. The measured correlators and their evolution from pp and p-Pb to Pb-Pb collisions are additionally compared to predictions from Monte Carlo event generators, and the potential presence of viscous effects is discussed.Two-particle transverse momentum differential correlators, recently measured in Pb--Pb collisions at energies available at the CERN Large Hadron Collider (LHC), provide an additional tool to gain insights into particle production mechanisms and infer transport properties, such as the ratio of shear viscosity to entropy density, of the medium created in Pb-Pb collisions. The longitudinal long-range correlations and the large azimuthal anisotropy measured at low transverse momenta in small collision systems, namely pp and p-Pb, at LHC energies resemble manifestations of collective behaviour. This suggests that locally equilibrated matter may be produced in these small collision systems, similar to what is observed in Pb-Pb collisions. In this work, the same two-particle transverse momentum differential correlators are exploited in pp and p-Pb collisions at s=7\sqrt{s} = 7 TeV and sNN=5.02\sqrt{s_{\rm NN}} = 5.02 TeV, respectively, to seek evidence for viscous effects. Specifically, the strength and shape of the correlators are studied as a function of the produced particle multiplicity to identify evidence for longitudinal broadening that might reveal the presence of viscous effects in these smaller systems. The measured correlators and their evolution from pp and p--Pb to Pb--Pb collisions are additionally compared to predictions from Monte Carlo event generators, and the potential presence of viscous effects is discussed.Two-particle transverse momentum differential correlators, recently measured in Pb-Pb collisions at energies available at the CERN Large Hadron Collider (LHC), provide an additional tool to gain insights into particle production mechanisms and infer transport properties, such as the ratio of shear viscosity to entropy density, of the medium created in Pb-Pb collisions. The longitudinal long-range correlations and the large azimuthal anisotropy measured at low transverse momenta in small collision systems, namely pp and p-Pb, at LHC energies resemble manifestations of collective behavior. This suggests that locally equilibrated matter may be produced in these small collision systems, similar to what is observed in Pb-Pb collisions. In this work, the same two-particle transverse momentum differential correlators are exploited in pp and p-Pb collisions at s=7TeV and sNN=5.02TeV, respectively, to seek evidence for viscous effects. Specifically, the strength and shape of the correlators are studied as a function of the produced particle multiplicity to identify evidence for longitudinal broadening that might reveal the presence of viscous effects in these smaller systems. The measured correlators and their evolution from pp and p-Pb to Pb-Pb collisions are additionally compared to predictions from Monte Carlo event generators, and the potential presence of viscous effects is discussed

    First measurement of Λc+\Lambda_\mathrm{c}^{+} production down to pT=0p_\mathrm{T} = 0 in pp and p-Pb collisions at sNN=5.02\sqrt{s_\mathrm{NN}} = 5.02 TeV

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    The production of prompt Λc+{\mathrm {\Lambda_{c}^{+}}} baryons has been measured at midrapidity in the transverse momentum interval 0 Λc+ baryons has been measured at midrapidity in the transverse momentum interval 0<pT<1 GeV/c for the first time, in pp and p–Pb collisions at a center-of-mass energy per nucleon-nucleon collision sNN=5.02TeV. The measurement was performed in the decay channel Λc+→pKS0 by applying new decay reconstruction techniques using a Kalman-Filter vertexing algorithm and adopting a machine-learning approach for the candidate selection. The pT-integrated Λc+ production cross sections in both collision systems were determined and used along with the measured yields in Pb–Pb collisions to compute the pT-integrated nuclear modification factors RpPb and RAA of Λc+ baryons, which are compared to model calculations that consider nuclear modification of the parton distribution functions. The Λc+/D0 baryon-to-meson yield ratio is reported for pp and p–Pb collisions. Comparisons with models that include modified hadronization processes are presented, and the implications of the results on the understanding of charm hadronization in hadronic collisions are discussed. A significant (3.7σ) modification of the mean transverse momentum of Λc+ baryons is seen in p–Pb collisions with respect to pp collisions, while the pT-integrated Λc+/D0 yield ratio was found to be consistent between the two collision systems within the uncertainties.The production of prompt \mathrm {\Lambda_{c}^{+}}baryonshasbeenmeasuredatmidrapidityinthetransversemomentuminterval baryons has been measured at midrapidity in the transverse momentum interval 0<p_{\rm T}<1GeV/ GeV/cforthefirsttime,inppandpPbcollisionsatacentreofmassenergypernucleonnucleoncollision for the first time, in pp and p-Pb collisions at a centre-of-mass energy per nucleon-nucleon collision \sqrt{s_\mathrm{NN}} = 5.02TeV.Themeasurementwasperformedinthedecaychannel TeV. The measurement was performed in the decay channel {\rm \Lambda_{c}^{+}\to p K^{0}_{S}}byapplyingnewdecayreconstructiontechniquesusingaKalmanFiltervertexingalgorithmandadoptingamachinelearningapproachforthecandidateselection.The by applying new decay reconstruction techniques using a Kalman-Filter vertexing algorithm and adopting a machine-learning approach for the candidate selection. The p_{\rm T}integrated-integrated \mathrm {\Lambda_{c}^{+}}productioncrosssectionsinbothcollisionsystemsweredeterminedandusedalongwiththemeasuredyieldsinPbPbcollisionstocomputethe production cross sections in both collision systems were determined and used along with the measured yields in Pb-Pb collisions to compute the p_{\rm T}integratednuclearmodificationfactors-integrated nuclear modification factors R_{\rm pPb}and and R_\mathrm{AA}of of \mathrm{\Lambda_{c}^{+}}baryons,whicharecomparedtomodelcalculationsthatconsidernuclearmodificationofthepartondistributionfunctions.The baryons, which are compared to model calculations that consider nuclear modification of the parton distribution functions. The \mathrm{\Lambda_{c}^{+}/D^0}baryontomesonyieldratioisreportedforppandpPbcollisions.Comparisonswithmodelsthatincludemodifiedhadronisationprocessesarepresented,andtheimplicationsoftheresultsontheunderstandingofcharmhadronisationinhadroniccollisionsarediscussed.Asignificant( baryon-to-meson yield ratio is reported for pp and p-Pb collisions. Comparisons with models that include modified hadronisation processes are presented, and the implications of the results on the understanding of charm hadronisation in hadronic collisions are discussed. A significant (3.7\sigma)modificationofthemeantransversemomentumof) modification of the mean transverse momentum of \mathrm {\Lambda_{c}^{+}}baryonsisseeninpPbcollisionswithrespecttoppcollisions,whilethe baryons is seen in p-Pb collisions with respect to pp collisions, while the p_{\rm T}integrated-integrated \mathrm{\Lambda_{c}^{+}/D^0}$ yield ratio was found to be consistent between the two collision systems within the uncertainties

    First measurement of antideuteron number fluctuations at energies available at the Large Hadron Collider

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    The first measurement of event-by-event antideuteron number fluctuations in high energy heavy-ion collisions is presented. The measurements are carried out at midrapidity (|\eta| |η|<0.8) as a function of collision centrality in Pb-Pb collisions at sNN=5.02  TeV using the ALICE detector. A significant negative correlation between the produced antiprotons and antideuterons is observed in all collision centralities. The results are compared with a state-of-the-art coalescence calculation. While it describes the ratio of higher order cumulants of the antideuteron multiplicity distribution, it fails to describe quantitatively the magnitude of the correlation between antiproton and antideuteron production. On the other hand, thermal-statistical model calculations describe all the measured observables within uncertainties only for correlation volumes that are different with respect to those describing proton yields and a similar measurement of net-proton number fluctuations.The first measurement of event-by-event antideuteron number fluctuations in high energy heavy-ion collisions is presented. The measurements are carried out at midrapidity (|\eta| < 0.8)asafunctionofcollisioncentralityinPb) as a function of collision centrality in Pb-PbcollisionsatPb collisions at \sqrt{s_{\rm NN}} = 5.02$ TeV using the ALICE detector. A significant negative correlation between the produced antiprotons and antideuterons is observed in all collision centralities. The results are compared with a state-of-the-art coalescence calculation. While it describes the ratio of higher order cumulants of the antideuteron multiplicity distribution, it fails to describe quantitatively the magnitude of the correlation between antiproton and antideuteron production. On the other hand, thermal-statistical model calculations describe all the measured observables within uncertainties only for correlation volumes that are different with respect to those describing proton yields and a similar measurement of net-proton number fluctuations

    Measurements of the groomed jet radius and momentum splitting fraction with the soft drop and dynamical grooming algorithms in pp collisions at s \sqrt{s} = 5.02 TeV

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    This article presents measurements of the groomed jet radius and momentum splitting fraction in pp collisions at s=5.02\sqrt{s}=5.02 TeV with the ALICE detector at the Large Hadron Collider. Inclusive charged-particle jets are reconstructed at midrapidity using the anti-kTk_{\rm{T}} algorithm for transverse momentum 60<pTch  jet<8060< p_{\mathrm{T}}^{\rm{ch\; jet}}<80 GeV/cc. We report results using two different grooming algorithms: soft drop and, for the first time, dynamical grooming. For each grooming algorithm, a variety of grooming settings are used in order to explore the impact of collinear radiation on these jet substructure observables. These results are compared to perturbative calculations that include resummation of large logarithms at all orders in the strong coupling constant. We find good agreement of the theoretical predictions with the data for all grooming settings considered.This article presents measurements of the groomed jet radius and momentum splitting fraction in pp collisions at s \sqrt{s} = 5.02 TeV with the ALICE detector at the Large Hadron Collider. Inclusive charged-particle jets are reconstructed at midrapidity using the anti-kT_{T} algorithm for transverse momentum 60<pTch  jet<80 60<{p}_{\textrm{T}}^{\textrm{ch}\;\textrm{jet}}<80 GeV/c. We report results using two different grooming algorithms: soft drop and, for the first time, dynamical grooming. For each grooming algorithm, a variety of grooming settings are used in order to explore the impact of collinear radiation on these jet substructure observables. These results are compared to perturbative calculations that include resummation of large logarithms at all orders in the strong coupling constant. We find good agreement of the theoretical predictions with the data for all grooming settings considered.[graphic not available: see fulltext]This article presents measurements of the groomed jet radius and momentum splitting fraction in pp collisions at s=5.02\sqrt{s}=5.02 TeV with the ALICE detector at the Large Hadron Collider. Inclusive charged-particle jets are reconstructed at midrapidity using the anti-kTk_{\rm{T}} algorithm for transverse momentum 60<pTch  jet<8060< p_{\mathrm{T}}^{\rm{ch\; jet}}<80 GeV/cc. We report results using two different grooming algorithms: soft drop and, for the first time, dynamical grooming. For each grooming algorithm, a variety of grooming settings are used in order to explore the impact of collinear radiation on these jet substructure observables. These results are compared to perturbative calculations that include resummation of large logarithms at all orders in the strong coupling constant. We find good agreement of the theoretical predictions with the data for all grooming settings considered

    Measurement of the angle between jet axes in pp collisions at s \sqrt{s} = 5.02 TeV

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    This article reports measurements of the angle between differently defined jet axes in pp collisions at s=5.02\sqrt{s} = 5.02 TeV carried out by the ALICE Collaboration. Charged particles at midrapidity are clustered into jets with resolution parameters R=0.2R=0.2 and 0.4. The jet axis, before and after Soft Drop grooming, is compared to the jet axis from the Winner-Takes-All (WTA) recombination scheme. The angle between these axes, ΔRaxis\Delta R_{\mathrm{axis}}, probes a wide phase space of the jet formation and evolution, ranging from the initial high-momentum-transfer scattering to the hadronization process. The ΔRaxis\Delta R_{\mathrm{axis}} observable is presented for 20<pTch  jet<10020 < {p_{\mathrm{T}}^{\mathrm{ch\; jet}}}< 100 GeV/cc, and compared to predictions from the PYTHIA 8 and Herwig 7 event generators. The distributions can also be calculated analytically with a leading hadronization correction related to the non-perturbative component of the Collins-Soper-Sterman (CSS) evolution kernel. Comparisons to analytical predictions at next-to-leading-logarithmic accuracy with leading hadronization correction implemented from experimental extractions of the CSS kernel in Drell-Yan measurements are presented. The analytical predictions describe the measured data within 20% in the perturbative regime, with surprising agreement in the non-perturbative regime as well. These results are compatible with the universality of the CSS kernel in the context of jet substructure.This article reports measurements of the angle between differently defined jet axes in pp collisions at s \sqrt{s} = 5.02 TeV carried out by the ALICE Collaboration. Charged particles at midrapidity are clustered into jets with resolution parameters R = 0.2 and 0.4. The jet axis, before and after Soft Drop grooming, is compared to the jet axis from the Winner-Takes-All (WTA) recombination scheme. The angle between these axes, ∆Raxis_{axis}, probes a wide phase space of the jet formation and evolution, ranging from the initial high-momentum-transfer scattering to the hadronization process. The ∆Raxis_{axis} observable is presented for 20 <pTch jet {p}_{\textrm{T}}^{\textrm{ch}\ \textrm{jet}} < 100 GeV/c, and compared to predictions from the PYTHIA 8 and Herwig 7 event generators. The distributions can also be calculated analytically with a leading hadronization correction related to the non-perturbative component of the Collins-Soper-Sterman (CSS) evolution kernel. Comparisons to analytical predictions at next-to-leading-logarithmic accuracy with leading hadronization correction implemented from experimental extractions of the CSS kernel in Drell-Yan measurements are presented. The analytical predictions describe the measured data within 20% in the perturbative regime, with surprising agreement in the non-perturbative regime as well. These results are compatible with the universality of the CSS kernel in the context of jet substructure.[graphic not available: see fulltext]This article reports measurements of the angle between differently defined jet axes in pp collisions at s=5.02\sqrt{s} = 5.02 TeV carried out by the ALICE Collaboration. Charged particles at midrapidity are clustered into jets with resolution parameters R=0.2R=0.2 and 0.4. The jet axis, before and after Soft Drop grooming, is compared to the jet axis from the Winner-Takes-All (WTA) recombination scheme. The angle between these axes, ΔRaxis\Delta R_{\mathrm{axis}}, probes a wide phase space of the jet formation and evolution, ranging from the initial high-momentum-transfer scattering to the hadronization process. The ΔRaxis\Delta R_{\mathrm{axis}} observable is presented for 20<pTch  jet<10020 < {p_{\mathrm{T}}^{\mathrm{ch\; jet}}}< 100 GeV/cc, and compared to predictions from the PYTHIA 8 and Herwig 7 event generators. The distributions can also be calculated analytically with a leading hadronization correction related to the non-perturbative component of the Collins-Soper-Sterman (CSS) evolution kernel. Comparisons to analytical predictions at next-to-leading-logarithmic accuracy with leading hadronization correction implemented from experimental extractions of the CSS kernel in Drell-Yan measurements are presented. The analytical predictions describe the measured data within 20% in the perturbative regime, with surprising agreement in the non-perturbative regime as well. These results are compatible with the universality of the CSS kernel in the context of jet substructure

    Investigation of <math><mrow><msup><mi>K</mi><mo>+</mo></msup><msup><mi>K</mi><mo>−</mo></msup></mrow></math> interactions via femtoscopy in Pb-Pb collisions at <math><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>2.76</mn></mrow></math> TeV at the CERN Large Hadron Collider

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    Femtoscopic correlations of nonidentical charged kaons (K+K−) are studied in Pb-Pb collisions at a center-of-mass energy per nucleon-nucleon collision sNN=2.76 TeV by ALICE at the CERN Large Hadron Collider. One-dimensional K+K− correlation functions are analyzed in three centrality classes and eight intervals of particle-pair transverse momentum. The Lednický and Luboshitz interaction model used in the K+K− analysis includes the final-state Coulomb interactions between kaons and the final-state interaction through a0(980) and f0(980) resonances. The mass of f0(980) and coupling were extracted from the fit to K+K− correlation functions using the femtoscopic technique. The measured mass and width of the f0(980) resonance are consistent with other published measurements. The height of the ϕ(1020) meson peak present in the K+K− correlation function rapidly decreases with increasing source radius, qualitatively in agreement with an inverse volume dependence. A phenomenological fit to this trend suggests that the ϕ(1020) meson yield is dominated by particles produced directly from the hadronization of the system. The small fraction subsequently produced by final-state interactions could not be precisely quantified with data presented in this paper and will be assessed in future work.Femtoscopic correlations of non-identical charged kaons (K+K\rm K^+ K^-) are studied in Pb-Pb collisions at a center-of-mass energy per nucleon-nucleon collision sNN=2.76\sqrt{s_{\mathrm{NN}}} =2.76 TeV by ALICE at the LHC. One-dimensional K+K\rm K^+ K^- correlation functions are analyzed in three centrality classes and eight intervals of particle-pair transverse momentum. The Lednický and Luboshitz interaction model used in the K+K\rm K^+ K^- analysis includes the final-state Coulomb interactions between kaons and the final-state interaction through a0a_{0}(980) and f0f_{0}(980) resonances. The mass of f0f_{0}(980) and coupling were extracted from the fit to K+K\rm K^+ K^- correlation functions using the femtoscopic technique. The measured mass and width of the f0f_{0}(980) resonance are consistent with other published measurements. The height of the ϕ\phi(1020) meson peak present in the K+K\rm K^+ K^- correlation function rapidly decreases with increasing source radius, qualitatively in agreement with an inverse volume dependence. A phenomenological fit to this trend suggests that the ϕ\phi(1020) meson yield is dominated by particles produced directly from the hadronization of the system. The small fraction subsequently produced by final-state interactions could not be precisely quantified with data presented in this paper and will be assessed in future work

    Production of KS0{\rm K}^{0}_{\rm{S}}, Λ\Lambda (Λ\overline{\Lambda}), Ξ±\Xi^{\pm} and Ω±\Omega^{\pm} in jets and in the underlying event in pp and p-Pb collisions

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    The production of strange hadrons (KS0{\rm K}^{0}_{\rm{S}}, Λ{\Lambda}, Ξ±\Xi^{\pm}, and Ω±\Omega^{\pm}), baryon-to-meson ratios (Λ/KS0{\Lambda}/{\rm K}^{0}_{\rm{S}}, Ξ/KS0\Xi/{\rm K}^{0}_{\rm{S}}, and Ω/KS0\Omega/{\rm K}^{0}_{\rm{S}}), and baryon-to-baryon ratios (Ξ/Λ\Xi/{\Lambda}, Ω/Λ\Omega/{\Lambda}, and Ω/Ξ\Omega/\Xi) associated with jets and the underlying event were measured as a function of transverse momentum (pTp_{\rm T}) in pp collisions at s=13\sqrt{s} = 13~TeV and p-Pb collisions at sNN=5.02\sqrt{s_{\rm NN}} = 5.02~TeV with the ALICE detector at the LHC. The inclusive production of the same particle species and the corresponding ratios are also reported. The production of multi-strange hadrons, Ξ±\Xi^{\pm} and Ω±\Omega^{\pm}, and their associated particle ratios in jets and in the underlying event are measured for the first time. In both pp and \pPb collisions, the baryon-to-meson and baryon-to-baryon yield ratios measured in jets differ from the inclusive particle production for low and intermediate hadron pTp_{\rm T} (0.6-6~GeV/cc). Ratios measured in the underlying event are in turn similar to those measured for inclusive particle production. In pp collisions, the particle production in jets is compared with PYTHIA 8 predictions with three colour-reconnection implementation modes. None of them fully reproduces the data in the measured hadron transverse momentum region. The maximum deviation is observed for Ξ±\Xi^{\pm} and Ω±\Omega^{\pm} which reaches a factor of about six. The event multiplicity dependence is further investigated in p-Pb collisions. In contrast to what is observed in the underlying event, there is no significant event-multiplicity dependence for particle production in jets. The presented measurements provide novel constraints on hadronisation and its Monte Carlo description. In particular, they demonstrate that the fragmentation of jets alone is insufficient to describe the strange and multi-strange particle production in hadronic collisions at LHC energies.The production of strange hadrons (KS0 {\textrm{K}}_{\textrm{S}}^0 , Λ, Ξ±^{±}, and Ω±^{±}), baryon-to-meson ratios (Λ/KS0 {\textrm{K}}_{\textrm{S}}^0 , Ξ/KS0 {\textrm{K}}_{\textrm{S}}^0 , and Ω/KS0 {\textrm{K}}_{\textrm{S}}^0 ), and baryon-to-baryon ratios (Ξ/Λ, Ω/Λ, and Ω/Ξ) associated with jets and the underlying event were measured as a function of transverse momentum (pT_{T}) in pp collisions at s \sqrt{s} = 13 TeV and p Pb collisions at sNN \sqrt{s_{\textrm{NN}}} = 5.02 TeV with the ALICE detector at the LHC. The inclusive production of the same particle species and the corresponding ratios are also reported. The production of multi-strange hadrons, Ξ±^{±} and Ω±^{±}, and their associated particle ratios in jets and in the underlying event are measured for the first time. In both pp and p–Pb collisions, the baryon-to-meson and baryon-to-baryon yield ratios measured in jets differ from the inclusive particle production for low and intermediate hadron pT_{T} (0.6–6 GeV/c). Ratios measured in the underlying event are in turn similar to those measured for inclusive particle production. In pp collisions, the particle production in jets is compared with Pythia 8 predictions with three colour-reconnection implementation modes. None of them fully reproduces the data in the measured hadron pT_{T} region. The maximum deviation is observed for Ξ±^{±} and Ω±^{±} which reaches a factor of about six. The event multiplicity dependence is further investigated in p−Pb collisions. In contrast to what is observed in the underlying event, there is no significant event-multiplicity dependence for particle production in jets. The presented measurements provide novel constraints on hadronisation and its Monte Carlo description. In particular, they demonstrate that the fragmentation of jets alone is insufficient to describe the strange and multi-strange particle production in hadronic collisions at LHC energies.[graphic not available: see fulltext]The production of strange hadrons (KS0^{0}_{\rm S}, Λ\Lambda, Ξ±\Xi^{\pm}, and Ω±\Omega^{\pm}), baryon-to-meson ratios (Λ/KS0\Lambda/{\rm K}^0_{\rm S}, Ξ/KS0\Xi/{\rm K}^0_{\rm S }, and Ω/KS0\Omega/{\rm K}^0_{\rm S}), and baryon-to-baryon ratios (Ξ/Λ\Xi/\Lambda, Ω/Λ\Omega/\Lambda, and Ω/Ξ\Omega/\Xi) associated with jets and the underlying event were measured as a function of transverse momentum (pTp_{\rm T}) in pp collisions at s=13\sqrt{s} = 13 TeV and p-Pb collisions at sNN=5.02\sqrt{s_{\rm NN}} = 5.02 TeV with the ALICE detector at the LHC. The inclusive production of the same particle species and the corresponding ratios are also reported. The production of multi-strange hadrons, Ξ±\Xi^{\pm} and Ω±\Omega^{\pm}, and their associated particle ratios in jets and in the underlying event are measured for the first time. In both pp and p-Pb collisions, the baryon-to-meson and baryon-to-baryon yield ratios measured in jets differ from the inclusive particle production for low and intermediate hadron pTp_{\rm T} (0.6-6 GeV/cc). Ratios measured in the underlying event are in turn similar to those measured for inclusive particle production. In pp collisions, the particle production in jets is compared with PYTHIA 8 predictions with three colour-reconnection implementation modes. None of them fully reproduces the data in the measured hadron pTp_{\rm T} region. The maximum deviation is observed for Ξ±\Xi^{\pm} and Ω±\Omega^{\pm}, which reaches a factor of about six. In p-Pb collisions, there is no significant event-multiplicity dependence for particle production in jets, in contrast to what is observed in the underlying event. The presented measurements provide novel constraints on hadronisation and its Monte Carlo description. In particular, they demonstrate that the fragmentation of jets alone is insufficient to describe the strange and multi-strange particle production in hadronic collisions at LHC energies

    J/ψ\psi production at midrapidity in p-Pb collisions at sNN=8.16\sqrt{s_{\rm NN}} = 8.16 TeV

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    The production of inclusive, prompt and non-prompt J/ψ\psi was studied for the first time at midrapidity (1.372 -1.37 2 \GeVc. The study of the J/ψ\psi mesons in the dielectron channel used for the first time in ALICE online single-electron triggers from the Transition Radiation Detector, providing a data sample corresponding to an integrated luminosity of 689±13μb1689 \pm 13 \mu{\rm b}^{-1}. The proton-proton reference cross section for inclusive J/ψ\psi was obtained based on interpolations of measured data at different centre-of-mass energies and a universal function describing the pTp_{\rm T}-differential J/ψ\psi production cross sections. The pTp_{\rm T}-differential nuclear modification factors RpPbR_{\rm pPb} of inclusive, prompt, and non-prompt J/ψ\psi are consistent with unity and described by theoretical models implementing only nuclear shadowing.The production of inclusive, prompt and non-prompt J/ψ was studied for the first time at midrapidity (−1.37 2 GeV/c. The study of the J/ψ mesons in the dielectron channel used for the first time in ALICE online single-electron triggers from the Transition Radiation Detector, providing a data sample corresponding to an integrated luminosity of 689 ± 13 μb1^{−1}. The proton-proton reference cross section for inclusive J/ψ was obtained based on interpolations of measured data at different centre-of-mass energies and a universal function describing the pT_{T}-differential J/ψ production cross sections. The pT_{T}-differential nuclear modification factors RpPb_{pPb} of inclusive, prompt, and non-prompt J/ψ are consistent with unity and described by theoretical models implementing only nuclear shadowing.[graphic not available: see fulltext]The production of inclusive, prompt and non-prompt J/ψ\psi was studied for the first time at midrapidity (1.372 -1.37 2 GeV/cc. The study of the J/ψ\psi mesons in the dielectron channel used for the first time in ALICE online single-electron triggers from the Transition Radiation Detector, providing a data sample corresponding to an integrated luminosity of 689±13μb1689 \pm 13 \mu{\rm b}^{-1}. The proton-proton reference cross section for inclusive J/ψ\psi was obtained based on interpolations of measured data at different centre-of-mass energies and a universal function describing the pTp_{\rm T}-differential J/ψ\psi production cross sections. The pTp_{\rm T}-differential nuclear modification factors RpPbR_{\rm pPb} of inclusive, prompt, and non-prompt J/ψ\psi are consistent with unity and described by theoretical models implementing only nuclear shadowing

    K(892)0\mathrm{K}^{*}(\mathrm{892})^{0} and ϕ(1020)\mathrm{\phi(1020)} production in p-Pb collisions at sNN\sqrt{s_{\rm NN}} = 8.16 TeV

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    The production of K(892)0\mathrm{K}^{*}(\mathrm{892})^{0} and ϕ(1020)\mathrm{\phi(1020)} resonances has been measured in p-Pb collisions at sNN\sqrt{s_{\rm NN}} = 8.16 TeV using the ALICE detector. Resonances are reconstructed via their hadronic decay channels in the rapidity interval -0.5 8 GeV/cc), the RpPbR_{\rm pPb} values of all hadrons are consistent with unity within uncertainties. The RpPbR_{\rm pPb} of K(892)0\mathrm{K}^{*}(\mathrm{892})^{0} and ϕ(1020)\mathrm{\phi(1020)} at sNN\sqrt{s_{\rm NN}} = 8.16 and 5.02 TeV show no significant energy dependence
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