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A study of$$ {\\Lambda}_b^0 $$Λ b 0 and$$ {\\Xi}_b^0 $$Ξ b 0 baryon decays to the final states$$ p{K}_{\\textrm{S}}^0{\\pi}^{-} $$p K S 0 π − and$$ p{K}_{\\textrm{S}}^0{K}^{-} $$p K S 0 K − is performed using pp collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb − 1 . The decays$$ {\\Lambda}_b^0\\to p{K}_{\\textrm{S}}^0{K}^{-} $$Λ b 0 → p K S 0 K − and$$ {\\Xi}_b^0\\to p{K}_{\\textrm{S}}^0{K}^{-} $$Ξ b 0 → p K S 0 K − are observed for the first time, with significances reaching eight standard deviations. The branching fractions and integrated CP asymmetries are measured for the$$ {\\Lambda}_b^0\\to p{K}_{\\textrm{S}}^0{\\pi}^{-} $$Λ b 0 → p K S 0 π − ,$$ {\\Lambda}_b^0\\to p{K}_{\\textrm{S}}^0{K}^{-} $$Λ b 0 → p K S 0 K − , and$$ {\\Xi}_b^0\\to p{K}_{\\textrm{S}}^0{K}^{-} $$Ξ b 0 → p K S 0 K − decays. For the decay$$ {\\Lambda}_b^0\\to p{K}_{\\textrm{S}}^0{\\pi}^{-} $$Λ b 0 → p K S 0 π − , the CP asymmetries are measured in different regions of the Dalitz plot. No evidence of CP violation is observed.

A time-integrated angular analysis of the decay$$ {B}_s^0\\to J/\\psi {\\overline{K}}^{\\ast }{(892)}^0 $$B s 0 → J / ψ K ¯ ∗ 892 0 , with J / ψ → μ + μ − and$$ {\\overline{K}}^{\\ast }{(892)}^0\\to {K}^{-}{\\pi}^{+} $$K ¯ ∗ 892 0 → K − π + , is presented. The analysis employs a sample of proton-proton collision data collected by the LHCb experiment during 2015–2018 at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb − 1 . A simultaneous maximum-likelihood fit is performed to the angular distributions in bins of the K − π + mass. This fit yields measurements of the CP -averaged polarisation fractions and CP asymmetries for the P-wave component of the K − π + system. The longitudinal and parallel polarisation fractions are determined to be f 0 = 0.534 ± 0.012 ± 0.009 and f || = 0.211 ± 0.014 ± 0.005, respectively, where the first uncertainty is statistical and the second is systematic. The CP asymmetries are measured with 3–7% precision and are found to be consistent with zero. These measurements, along with an updated determination of the branching fraction relative to the B 0 → J / ψK *0 decay, are combined with previous LHCb results, providing the most precise values for these observables to date.

Branching fraction ratios between the decays$$ {B}_{(s)}^0\\to J/\\psi {\\eta}^{\\left(\\prime \\right)} $$B s 0 → J / ψ η ′ are measured using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb − 1 . The measured ratios of these branching fractions are$$ {\\displaystyle \\begin{array}{c}\\frac{\\mathcal{B}\\left({B}^0\\to J/{\\psi \\eta}^{\\prime}\\right)}{\\mathcal{B}\\left({B}^0\\to J/\\psi \\eta \\right)}=0.48\\pm 0.06\\pm 0.02\\pm 0.01,\\\ {}\\frac{\\mathcal{B}\\left({B}_s^0\\to J/{\\psi \\eta}^{\\prime}\\right)}{\\mathcal{B}\\left({B}_s^0\\to J/\\psi \\eta \\right)}=0.80\\pm 0.02\\pm 0.02\\pm 0.01,\\end{array}} $$B B 0 → J / ψη ′ B B 0 → J / ψη = 0.48 ± 0.06 ± 0.02 ± 0.01 , B B s 0 → J / ψη ′ B B s 0 → J / ψη = 0.80 ± 0.02 ± 0.02 ± 0.01 , where the uncertainties are statistical, systematic and related to the precision of the η (′) branching fractions, respectively. They are used to constrain the η/η ′ mixing angle, ϕ P , and to probe the presence of a possible glueball component in the η ′ meson, described by the gluonic mixing angle ϕ G . The obtained results are$$ {\\displaystyle \\begin{array}{c}{\\phi}_{\\textrm{P}}={\\left({41.6}_{-1.2}^{+1.0}\\right)}^{\\circ },\\\ {}{\\phi}_{\\textrm{G}}={\\left({28.1}_{-4.0}^{+3.9}\\right)}^{\\circ },\\end{array}} $$ϕ P = 41.6 − 1.2 + 1.0 ∘ , ϕ G = 28.1 − 4.0 + 3.9 ∘ , where the uncertainties are statistically dominated. While the value of ϕ P is compatible with existing experimental determinations and theoretical calculations, the angle ϕ G differs from zero by more than four standard deviations, which points to a substantial glueball component in the η ′ meson and/or unexpectedly large contributions from gluon-mediated processes in these decays. The absolute branching fractions are also measured relative to that of the well-established$$ {B}_s^0\\to J/\\psi \\phi $$B s 0 → J / ψϕ decay, which serves as the normalisation channel. These results supersede the previous LHCb measurements and are the most precise to date.

The lifetimes of the$$ {\\varOmega}_c^0 $$Ω c 0 and$$ {\\Xi}_c^0 $$Ξ c 0 baryons are measured using a pp collision dataset collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb − 1 . The charm baryons are produced in the fully reconstructed decay chains$$ {\\varOmega}_b^{-}\\to {\\varOmega}_c^0\\left(\\to p{K}^{-}{K}^{-}{\\pi}^{+}\\right){\\pi}^{-} $$Ω b − → Ω c 0 → p K − K − π + π − and$$ {\\Xi}_b^{-}\\to {\\Xi}_c^0\\left(\\to p{K}^{-}{K}^{-}{\\pi}^{+}\\right){\\pi}^{-} $$Ξ b − → Ξ c 0 → p K − K − π + π − . The measurement uses topologically and kinematically similar B − → D 0 (→ K − K + π − π + ) π − decays for normalisation. The measured lifetimes are$$ {\\displaystyle \\begin{array}{c}{\\tau}_{\\varOmega_c^0}=276.3\\pm 19.4\\left(\\textrm{stat}\\right)\\pm 1.8\\left(\\textrm{syst}\\right)\\pm 0.7\\left({\\tau}_{D^0}\\right)\\textrm{fs},\\\ {}{\\tau}_{\\Xi_c^0}=149.2\\pm 2.5\\left(\\textrm{stat}\\right)\\pm 0.9\\left(\\textrm{syst}\\right)\\pm 0.4\\ \\left({\\tau}_{D^0}\\right)\\textrm{fs},\\end{array}} $$τ Ω c 0 = 276.3 ± 19.4 stat ± 1.8 syst ± 0.7 τ D 0 fs , τ Ξ c 0 = 149.2 ± 2.5 stat ± 0.9 syst ± 0.4 τ D 0 fs , where the first uncertainty is statistical, the second systematic and the third due to the uncertainty of the D 0 lifetime. These results are consistent with previous measurements performed by the LHCb experiment.

Abstract Branching fraction ratios between the decays B s 0 → J / ψ η ′ $$ {B}_{(s)}^0\\to J/\\psi {\\eta}^{\\left(\\prime \\right)} $$ are measured using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb −1. The measured ratios of these branching fractions are B B 0 → J / ψη ′ B B 0 → J / ψη = 0.48 ± 0.06 ± 0.02 ± 0.01 , B B s 0 → J / ψη ′ B B s 0 → J / ψη = 0.80 ± 0.02 ± 0.02 ± 0.01 , $$ {\\displaystyle \\begin{array}{c}\\frac{\\mathcal{B}\\left({B}^0\\to J/{\\psi \\eta}^{\\prime}\\right)}{\\mathcal{B}\\left({B}^0\\to J/\\psi \\eta \\right)}=0.48\\pm 0.06\\pm 0.02\\pm 0.01,\\\ {}\\frac{\\mathcal{B}\\left({B}_s^0\\to J/{\\psi \\eta}^{\\prime}\\right)}{\\mathcal{B}\\left({B}_s^0\\to J/\\psi \\eta \\right)}=0.80\\pm 0.02\\pm 0.02\\pm 0.01,\\end{array}} $$ where the uncertainties are statistical, systematic and related to the precision of the η (′) branching fractions, respectively. They are used to constrain the η/η′ mixing angle, ϕ P, and to probe the presence of a possible glueball component in the η′ meson, described by the gluonic mixing angle ϕ G. The obtained results are ϕ P = 41.6 − 1.2 + 1.0 ∘ , ϕ G = 28.1 − 4.0 + 3.9 ∘ , $$ {\\displaystyle \\begin{array}{c}{\\phi}_{\\textrm{P}}={\\left({41.6}_{-1.2}^{+1.0}\\right)}^{\\circ },\\\ {}{\\phi}_{\\textrm{G}}={\\left({28.1}_{-4.0}^{+3.9}\\right)}^{\\circ },\\end{array}} $$ where the uncertainties are statistically dominated. While the value of ϕ P is compatible with existing experimental determinations and theoretical calculations, the angle ϕ G differs from zero by more than four standard deviations, which points to a substantial glueball component in the η′ meson and/or unexpectedly large contributions from gluon-mediated processes in these decays. The absolute branching fractions are also measured relative to that of the well-established B s 0 → J / ψϕ $$ {B}_s^0\\to J/\\psi \\phi $$ decay, which serves as the normalisation channel. These results supersede the previous LHCb measurements and are the most precise to date.

Abstract A time-integrated angular analysis of the decay B s 0 → J / ψ K ¯ ∗ 892 0 $$ {B}_s^0\\to J/\\psi {\\overline{K}}^{\\ast }{(892)}^0 $$ , with J/ψ → μ + μ − and K ¯ ∗ 892 0 → K − π + $$ {\\overline{K}}^{\\ast }{(892)}^0\\to {K}^{-}{\\pi}^{+} $$ , is presented. The analysis employs a sample of proton-proton collision data collected by the LHCb experiment during 2015–2018 at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb −1. A simultaneous maximum-likelihood fit is performed to the angular distributions in bins of the K − π + mass. This fit yields measurements of the CP-averaged polarisation fractions and CP asymmetries for the P-wave component of the K − π + system. The longitudinal and parallel polarisation fractions are determined to be f 0 = 0.534 ± 0.012 ± 0.009 and f || = 0.211 ± 0.014 ± 0.005, respectively, where the first uncertainty is statistical and the second is systematic. The CP asymmetries are measured with 3–7% precision and are found to be consistent with zero. These measurements, along with an updated determination of the branching fraction relative to the B 0 → J/ψK *0 decay, are combined with previous LHCb results, providing the most precise values for these observables to date.

Abstract A study of Λ b 0 $$ {\\Lambda}_b^0 $$ and Ξ b 0 $$ {\\Xi}_b^0 $$ baryon decays to the final states p K S 0 π − $$ p{K}_{\\textrm{S}}^0{\\pi}^{-} $$ and p K S 0 K − $$ p{K}_{\\textrm{S}}^0{K}^{-} $$ is performed using pp collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb −1. The decays Λ b 0 → p K S 0 K − $$ {\\Lambda}_b^0\\to p{K}_{\\textrm{S}}^0{K}^{-} $$ and Ξ b 0 → p K S 0 K − $$ {\\Xi}_b^0\\to p{K}_{\\textrm{S}}^0{K}^{-} $$ are observed for the first time, with significances reaching eight standard deviations. The branching fractions and integrated CP asymmetries are measured for the Λ b 0 → p K S 0 π − $$ {\\Lambda}_b^0\\to p{K}_{\\textrm{S}}^0{\\pi}^{-} $$ , Λ b 0 → p K S 0 K − $$ {\\Lambda}_b^0\\to p{K}_{\\textrm{S}}^0{K}^{-} $$ , and Ξ b 0 → p K S 0 K − $$ {\\Xi}_b^0\\to p{K}_{\\textrm{S}}^0{K}^{-} $$ decays. For the decay Λ b 0 → p K S 0 π − $$ {\\Lambda}_b^0\\to p{K}_{\\textrm{S}}^0{\\pi}^{-} $$ , the CP asymmetries are measured in different regions of the Dalitz plot. No evidence of CP violation is observed.

Abstract The lifetimes of the Ω c 0 $$ {\\varOmega}_c^0 $$ and Ξ c 0 $$ {\\Xi}_c^0 $$ baryons are measured using a pp collision dataset collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb −1. The charm baryons are produced in the fully reconstructed decay chains Ω b − → Ω c 0 → p K − K − π + π − $$ {\\varOmega}_b^{-}\\to {\\varOmega}_c^0\\left(\\to p{K}^{-}{K}^{-}{\\pi}^{+}\\right){\\pi}^{-} $$ and Ξ b − → Ξ c 0 → p K − K − π + π − $$ {\\Xi}_b^{-}\\to {\\Xi}_c^0\\left(\\to p{K}^{-}{K}^{-}{\\pi}^{+}\\right){\\pi}^{-} $$ . The measurement uses topologically and kinematically similar B − → D 0(→ K − K + π − π +)π − decays for normalisation. The measured lifetimes are τ Ω c 0 = 276.3 ± 19.4 stat ± 1.8 syst ± 0.7 τ D 0 fs , τ Ξ c 0 = 149.2 ± 2.5 stat ± 0.9 syst ± 0.4 τ D 0 fs , $$ {\\displaystyle \\begin{array}{c}{\\tau}_{\\varOmega_c^0}=276.3\\pm 19.4\\left(\\textrm{stat}\\right)\\pm 1.8\\left(\\textrm{syst}\\right)\\pm 0.7\\left({\\tau}_{D^0}\\right)\\textrm{fs},\\\ {}{\\tau}_{\\Xi_c^0}=149.2\\pm 2.5\\left(\\textrm{stat}\\right)\\pm 0.9\\left(\\textrm{syst}\\right)\\pm 0.4\\ \\left({\\tau}_{D^0}\\right)\\textrm{fs},\\end{array}} $$ where the first uncertainty is statistical, the second systematic and the third due to the uncertainty of the D 0 lifetime. These results are consistent with previous measurements performed by the LHCb experiment.

There is great scientific and popular interest in understanding the genetic history of populations in the Americas. We wish to understand when different regions of the continent were inhabited, where settlers came from, and how current inhabitants relate genetically to earlier populations. Recent studies unraveled parts of the genetic history of the continent using genotyping arrays and uniparental markers. The 1000 Genomes Project provides a unique opportunity for improving our understanding of population genetic history by providing over a hundred sequenced low coverage genomes and exomes from Colombian (CLM), Mexican-American (MXL), and Puerto Rican (PUR) populations. Here, we explore the genomic contributions of African, European, and especially Native American ancestry to these populations. Estimated Native American ancestry is 48% in MXL, 25% in CLM, and 13% in PUR. Native American ancestry in PUR is most closely related to populations surrounding the Orinoco River basin, confirming the Southern American ancestry of the Taíno people of the Caribbean. We present new methods to estimate the allele frequencies in the Native American fraction of the populations, and model their distribution using a demographic model for three ancestral Native American populations. These ancestral populations likely split in close succession: the most likely scenario, based on a peopling of the Americas 16 thousand years ago (kya), supports that the MXL Ancestors split 12.2kya, with a subsequent split of the ancestors to CLM and PUR 11.7kya. The model also features effective populations of 62,000 in Mexico, 8,700 in Colombia, and 1,900 in Puerto Rico. Modeling Identity-by-descent (IBD) and ancestry tract length, we show that post-contact populations also differ markedly in their effective sizes and migration patterns, with Puerto Rico showing the smallest effective size and the earlier migration from Europe. Finally, we compare IBD and ancestry assignments to find evidence for relatedness among European founders to the three populations.

Mexico harbors great cultural and ethnic diversity, yet fine-scale patterns of human genome-wide variation from this region remain largely uncharacterized. We studied genomic variation within Mexico from over 1000 individuals representing 20 indigenous and 11 mestizo populations. We found striking genetic stratification among indigenous populations within Mexico at varying degrees of geographic isolation. Some groups were as differentiated as Europeans are from East Asians. Pre-Columbian genetic substructure is recapitulated in the indigenous ancestry of admixed mestizo individuals across the country. Furthermore, two independently phenotyped cohorts of Mexicans and Mexican Americans showed a significant association between subcontinental ancestry and lung function. Thus, accounting for fine-scale ancestry patterns is critical for medical and population genetic studies within Mexico, in Mexican-descent populations, and likely in many other populations worldwide.