ORCID Profile
0000-0003-4868-8601
Current Organisation
University of Aberdeen
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Publisher: Elsevier BV
Date: 11-1999
Publisher: Springer Science and Business Media LLC
Date: 31-03-2009
DOI: 10.1038/NGEO479
Publisher: Elsevier BV
Date: 06-1990
Publisher: Geological Society of America
Date: 06-11-2015
DOI: 10.1130/G37245.1
Publisher: American Physical Society (APS)
Date: 08-03-2017
Publisher: Geological Society of London
Date: 2006
Publisher: American Geophysical Union (AGU)
Date: 2012
DOI: 10.1029/2011JB008431
Publisher: Cambridge University Press
Date: 24-04-2014
Publisher: Geological Society of London
Date: 23-05-2017
DOI: 10.1144/SP460.12
Publisher: Elsevier BV
Date: 11-2020
Publisher: Cambridge University Press (CUP)
Date: 22-11-2018
DOI: 10.1017/S0016756818000651
Abstract: The Iberia–Newfoundland continental margin is one of the most-studied conjugate margins in the world. However, many unknowns remain regarding the nature of rifting preceding its break-up. We analyse a large dataset of tectonic subsidence curves, created from publicly available well data, to show spatial and temporal trends of rifting in the proximal domains of the margin. We develop a novel methodology of bulk averaging tectonic subsidence curves that can be applied on any conjugate margin with a similar spread of well data. The method does not rely on the existence of conjugate, deep seismic profiles and, specifically, attempts to forego the risk of quantitative bias derived from localized anomalies and uncertain stratigraphic dating and correlation. Results for the Iberia–Newfoundland margin show that active rift-driven tectonic subsidence occurred in the Central segment of the conjugate margin from c. 227 Ma (early Norian) to c. 152.1 Ma (early Tithonian), in the southern segment from c. 208.5 Ma (early Rhaetian) to c. 152.1 Ma (early Tithonian) and in the northern segment from c. 201.3 Ma (early Hettangian) to c. 132.9 Ma (early Hauterivian). This indicates that rifting in the stretching phase of the proximal domain of the Iberia–Newfoundland margin does not mirror hyperextended domain rifting trends (south to north) that ultimately led to break-up. The insights into broad-scale three-dimensional spatial and temporal trends, produced using the novel methodology presented in this paper, provide added value for interpretation of the development of passive margins, and new constraints for modelling of the formation of conjugate margins.
Publisher: Springer Science and Business Media LLC
Date: 10-2020
DOI: 10.1140/EPJC/S10052-020-8365-0
Abstract: A first search for $$CP$$ CP violation in the Cabibbo-suppressed $${{{\\varXi }} ^+_{c}} \\rightarrow {p} {{K} ^-} {{\\pi } ^+} $$ Ξ c + → p K - π + decay is performed using both a binned and an unbinned model-independent technique in the Dalitz plot. The studies are based on a s le of proton-proton collision data, corresponding to an integrated luminosity of $$3.0\\,\\text {fb} ^{-1} $$ 3.0 fb - 1 , and collected by the LHCb experiment at centre-of-mass energies of 7 and $$8\\,\\text {TeV} $$ 8 TeV . The data are consistent with the hypothesis of no $$CP$$ CP violation.
Publisher: Elsevier BV
Date: 08-2021
Publisher: American Geophysical Union (AGU)
Date: 18-10-2011
DOI: 10.1029/2011EO420002
Publisher: Elsevier BV
Date: 03-2004
Publisher: Elsevier BV
Date: 03-2004
Publisher: Elsevier BV
Date: 03-2004
Publisher: American Physical Society (APS)
Date: 12-11-2020
Publisher: Geological Society of London
Date: 17-10-2024
DOI: 10.1144/M57-2022-54
Publisher: Oxford University Press (OUP)
Date: 05-1984
Publisher: Springer Science and Business Media LLC
Date: 03-2021
DOI: 10.1140/EPJC/S10052-021-08994-0
Abstract: Long-lived particles decaying to $${e ^\\pm } {\\mu ^\\mp } {\\nu } $$ e ± μ ∓ ν , with masses between 7 and $$50 \\,\\text {GeV/}c^2 $$ 50 GeV/ c 2 and lifetimes between 2 and $$50 \\,\\text {ps} $$ 50 ps , are searched for by looking at displaced vertices containing electrons and muons of opposite charges. The search is performed using $$5.4 \\,\\text {fb} ^{-1} $$ 5.4 fb - 1 of $$p $$ p $$p $$ p collisions collected with the LHCb detector at a centre-of-mass energy of $$\\sqrt{s} = 13 \\,\\text {TeV} $$ s = 13 TeV . Three mechanisms of production of long-lived particles are considered: the direct pair production from quark interactions, the pair production from the decay of a Standard-Model-like Higgs boson with a mass of $$125 \\,\\text {GeV/}c^2 $$ 125 GeV/ c 2 , and the charged current production from an on-shell $$W $$ W boson with an additional lepton. No evidence of these long-lived states is obtained and upper limits on the production cross-section times branching fraction are set on the different production modes.
Publisher: Springer Science and Business Media LLC
Date: 06-2021
Abstract: Searches for CP violation in the two-body decays $$ {D}_{(s)}^{+}\\to {h}^{+}{\\pi}^0 $$ D s + → h + π 0 and $$ {D}_{(s)}^{+}\\to {h}^{+}\\eta $$ D s + → h + η (where h + denotes a π + or K + meson) are performed using pp collision data collected by the LHCb experiment corresponding to either 9 fb − 1 or 6 fb − 1 of integrated luminosity. The π 0 and η mesons are reconstructed using the e + e − γ final state, which can proceed as three-body decays π 0 → e + e − γ and η → e + e − γ , or via the two-body decays π 0 → γγ and η → γγ followed by a photon conversion. The measurements are made relative to the control modes $$ {D}_{(s)}^{+}\\to {K}_{\\mathrm{S}}^0{h}^{+} $$ D s + → K S 0 h + to cancel the production and detection asymmetries. The CP asymmetries are measured to be $$ {\\displaystyle \\begin{array}{c}{\\mathcal{A}}_{CP}\\left({D}^{+}\\to {\\pi}^{+}{\\pi}^0\\right)=\\left(-1.3\\pm 0.9\\pm 0.6\\right)\\%,\\\\ {}{\\mathcal{A}}_{CP}\\left({D}^{+}\\to {K}^{+}{\\pi}^0\\right)=\\left(-3.2\\pm 4.7\\pm 2.1\\right)\\%,\\\\ {}\\begin{array}{c}{\\mathcal{A}}_{CP}\\left({D}^{+}\\to {\\pi}^{+}\\eta \\right)=\\left(-0.2\\pm 0.8\\pm 0.4\\right)\\%,\\\\ {}{\\mathcal{A}}_{CP}\\left({D}^{+}\\to {K}^{+}\\eta \\right)=\\left(-6\\pm 10\\pm 4\\right)\\%,\\\\ {}\\begin{array}{c}{\\mathcal{A}}_{CP}\\left({D}_s^{+}\\to {K}^{+}{\\pi}^0\\right)=\\left(-0.8\\pm 3.9\\pm 1.2\\right)\\%,\\\\ {}\\begin{array}{c}{\\mathcal{A}}_{CP}\\left({D}_s^{+}\\to {\\pi}^{+}\\eta \\right)=\\left(0.8\\pm 0.7\\pm 0.5\\right)\\%,\\\\ {}{\\mathcal{A}}_{CP}\\left({D}_s^{+}\\to {K}^{+}\\eta \\right)=\\left(0.9\\pm 3.7\\pm 1.1\\right)\\%,\\end{array}\\end{array}\\end{array}\\end{array}} $$ A CP D + → π + π 0 = − 1.3 ± 0.9 ± 0.6 % , A CP D + → K + π 0 = − 3.2 ± 4.7 ± 2.1 % , A CP D + → π + η = − 0.2 ± 0.8 ± 0.4 % , A CP D + → K + η = − 6 ± 10 ± 4 % , A CP D s + → K + π 0 = − 0.8 ± 3.9 ± 1.2 % , A CP D s + → π + η = 0.8 ± 0.7 ± 0.5 % , A CP D s + → K + η = 0.9 ± 3.7 ± 1.1 % , where the first uncertainties are statistical and the second systematic. These results are consistent with no CP violation and mostly constitute the most precise measurements of $$ {\\mathcal{A}}_{CP} $$ A CP in these decay modes to date.
Publisher: Elsevier BV
Date: 02-2011
Publisher: Elsevier BV
Date: 03-2021
Publisher: Springer Science and Business Media LLC
Date: 11-2021
Abstract: An angular analysis of the rare decay $$ {B}_s^0 $$ B s 0 → ϕμ + μ − is presented, 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 8.4 fb − 1 . The observables describing the angular distributions of the decay $$ {B}_s^0 $$ B s 0 → ϕμ + μ − are determined in regions of q 2 , the square of the dimuon invariant mass. The results are consistent with Standard Model predictions.
Publisher: Elsevier BV
Date: 06-1996
Publisher: Wiley
Date: 19-06-2018
DOI: 10.1111/BRE.12301
Publisher: Elsevier BV
Date: 11-2020
Publisher: Springer Science and Business Media LLC
Date: 02-2021
Abstract: The decays $$ {\\mathrm{B}}_{\\mathrm{s}}^0 $$ B s 0 → J / ψπ + π − 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 $$ {\\mathrm{B}}_{\\mathrm{s}}^0 $$ B s 0 → $$ \\mathrm{J}/{\\uppsi \\mathrm{K}}^{\\ast 0}{\\overline{\\mathrm{K}}}^{\\ast 0} $$ J / ψK ∗ 0 K ¯ ∗ 0 and $$ {\\mathrm{B}}_{\\mathrm{s}}^0 $$ B s 0 → χ c1 (3872)K + K − , where the K + K − pair does not originate from a ϕ meson, are observed for the first time. Precise measurements of the ratios of branching fractions between intermediate χ c1 (3872)ϕ, $$ \\mathrm{J}/{\\uppsi \\mathrm{K}}^{\\ast 0}{\\overline{\\mathrm{K}}}^{\\ast 0} $$ J / ψK ∗ 0 K ¯ ∗ 0 , ψ(2S)ϕ and χ c1 (3872)K + K − states are reported. A structure, denoted as X(4740), is observed in the J / ψϕ mass spectrum and, assuming a Breit-Wigner parameterisation, its mass and width are determined to be $$ {\\displaystyle \\begin{array}{c}{m}_{\\mathrm{X}(4740)}=4741\\pm 6\\pm 6\\kern0.5em \\mathrm{MeV}/{c}^2,\\\\ {}{\\Gamma}_{\\mathrm{X}(4740)}=53\\pm 15\\pm 11\\kern0.5em \\mathrm{MeV},\\end{array}} $$ m X 4740 = 4741 ± 6 ± 6 MeV / c 2 , Γ X 4740 = 53 ± 15 ± 11 MeV , where the first uncertainty is statistical and the second is systematic. In addition, the most precise single measurement of the mass of the $$ {\\mathrm{B}}_{\\mathrm{s}}^0 $$ B s 0 meson is performed and gives a value of $$ {m}_{{\\mathrm{B}}_{\\mathrm{s}}^0}=5366.98\\pm 0.07\\pm 0.13\\kern0.5em \\mathrm{MeV}/{c}^2. $$ m B s 0 = 5366.98 ± 0.07 ± 0.13 MeV / c 2 .
Publisher: Elsevier BV
Date: 07-2014
Publisher: American Physical Society (APS)
Date: 17-08-2021
Publisher: Springer Science and Business Media LLC
Date: 02-2021
Abstract: The inclusive $$ b\\overline{b} $$ b b ¯ - and $$ c\\overline{c} $$ c c ¯ -dijet production cross-sections in the forward region of pp collisions are measured using a data s le collected with the LHCb detector at a centre-of-mass energy of 13 TeV in 2016. The data s le corresponds to an integrated luminosity of 1.6 fb − 1 . Differential cross-sections are measured as a function of the transverse momentum and of the pseudorapidity of the leading jet, of the rapidity difference between the jets, and of the dijet invariant mass. A fiducial region for the measurement is defined by requiring that the two jets originating from the two b or c quarks are emitted with transverse momentum greater than 20 GeV/ c , pseudorapidity in the range 2 . 2 η 4 . 2, and with a difference in the azimuthal angle between the two jets greater than 1.5. The integrated $$ b\\overline{b} $$ b b ¯ -dijet cross-section is measured to be 53 . 0 ± 9 . 7 nb, and the total $$ c\\overline{c} $$ c c ¯ -dijet cross-section is measured to be 73 ± 16 nb. The ratio between $$ c\\overline{c} $$ c c ¯ - and $$ b\\overline{b} $$ b b ¯ -dijet cross-sections is also measured and found to be 1 . 37 ± 0 . 27. The results are in agreement with theoretical predictions at next-to-leading order.
Publisher: Elsevier BV
Date: 2009
Publisher: Elsevier BV
Date: 10-2009
Publisher: Elsevier BV
Date: 12-2005
Publisher: American Geophysical Union (AGU)
Date: 04-1994
DOI: 10.1029/93TC02251
Publisher: Elsevier BV
Date: 11-1993
Publisher: American Physical Society (APS)
Date: 20-08-2021
Publisher: Informa UK Limited
Date: 04-1997
Publisher: American Geophysical Union (AGU)
Date: 31-10-2009
DOI: 10.1029/2008JB006124
Publisher: Elsevier BV
Date: 09-2009
Publisher: Elsevier BV
Date: 07-2007
Publisher: American Physical Society (APS)
Date: 20-02-2020
Publisher: American Physical Society (APS)
Date: 07-12-2020
Publisher: Elsevier BV
Date: 03-1991
Publisher: American Physical Society (APS)
Date: 20-11-2020
Publisher: American Physical Society (APS)
Date: 22-04-2021
Publisher: Elsevier BV
Date: 08-2010
Publisher: Elsevier BV
Date: 03-2021
Publisher: Elsevier BV
Date: 06-2020
Publisher: Geological Society of London
Date: 2006
Publisher: Springer Science and Business Media LLC
Date: 12-2020
Abstract: A measurement of four branching-fraction ratios for three-body decays of B mesons involving two open-charm hadrons in the final state is presented. Run 1 and Run 2 pp collision data are used, recorded by the LHCb experiment at centre-of-mass energies 7, 8, and 13 TeV and corresponding to an integrated luminosity of 9 fb − 1 . The measured branching-fraction ratios are $$ {\\displaystyle \\begin{array}{c}\\frac{\\mathcal{B}\\left({B}^{+}\\to {D}^{\\ast +}{D}^{-}{K}^{+}\\right)}{\\mathcal{B}\\left({B}^{+}\\to {\\overline{D}}^0{D}^0{K}^{+}\\right)}=0.517\\pm 0.015\\pm 0.013\\pm 0.011,\\\\ {}\\frac{\\mathcal{B}\\left({B}^{+}\\to {D}^{\\ast -}{D}^{+}{K}^{+}\\right)}{\\mathcal{B}\\left({B}^{+}\\to {\\overline{D}}^0{D}^0{K}^{+}\\right)}=0.577\\pm 0.016\\pm 0.013\\pm 0.013,\\\\ {}\\begin{array}{c}\\frac{\\mathcal{B}\\left({B}^0\\to {D}^{\\ast -}{D}^0{K}^{+}\\right)}{\\mathcal{B}\\left({B}^0\\to {D}^{-}{D}^0{K}^{+}\\right)}=1.754\\pm 0.028\\pm 0.016\\pm 0.035,\\\\ {}\\frac{\\mathcal{B}\\left({B}^{+}\\to {D}^{\\ast +}{D}^{-}{K}^{+}\\right)}{\\mathcal{B}\\left({B}^{+}\\to {D}^{\\ast -}{D}^{+}{K}^{+}\\right)}=0.907\\pm 0.033\\pm 0.014,\\end{array}\\end{array}} $$ B B + → D ∗ + D − K + B B + → D ¯ 0 D 0 K + = 0.517 ± 0.015 ± 0.013 ± 0.011 , B B + → D ∗ − D + K + B B + → D ¯ 0 D 0 K + = 0.577 ± 0.016 ± 0.013 ± 0.013 , B B 0 → D ∗ − D 0 K + B B 0 → D − D 0 K + = 1.754 ± 0.028 ± 0.016 ± 0.035 , B B + → D ∗ + D − K + B B + → D ∗ − D + K + = 0.907 ± 0.033 ± 0.014 , where the first of the uncertainties is statistical, the second systematic, and the third is due to the uncertainties on the D -meson branching fractions. These are the most accurate measurements of these ratios to date.
Publisher: Springer Science and Business Media LLC
Date: 08-2020
Abstract: The decays B + → J / ψπ + π − 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 between 2011 and 2018. Precise measurements of the ratios of branching fractions with the intermediate ψ 2 (3823), χ c1 (3872) and ψ(2S) states are reported. The values are $$ {\\displaystyle \\begin{array}{c}\\frac{{\\mathcal{B}}_{{\\mathrm{B}}^{+}\\to {\\uppsi}_2(3823){\\mathrm{K}}^{+}}\\times {\\mathcal{B}}_{\\uppsi_2(3823)\\to \\mathrm{J}/{\\uppsi \\uppi}^{+}{\\uppi}^{-}}}{{\\mathcal{B}}_{{\\mathrm{B}}^{+}\\to {\\upchi}_{\\mathrm{c}1}(3872){\\mathrm{K}}^{+}}\\times {\\mathcal{B}}_{\\upchi_{\\mathrm{c}1}(3872)\\to \\mathrm{J}/{\\uppsi \\uppi}^{+}{\\uppi}^{-}}}=\\left(3.56\\pm 0.67\\pm 0.11\\right)\\times {10}^{-2},\\\\ {}\\frac{{\\mathcal{B}}_{{\\mathrm{B}}^{+}\\to {\\uppsi}_2(3823){\\mathrm{K}}^{+}}\\times {\\mathcal{B}}_{\\uppsi_2(3823)\\to \\mathrm{J}/{\\uppsi \\uppi}^{+}{\\uppi}^{-}}}{{\\mathcal{B}}_{{\\mathrm{B}}^{+}\\to \\uppsi \\left(2\\mathrm{S}\\right){\\mathrm{K}}^{+}}\\times {\\mathcal{B}}_{\\uppsi \\left(2\\mathrm{S}\\right)\\to \\mathrm{J}/{\\uppsi \\uppi}^{+}{\\uppi}^{-}}}=\\left(1.31\\pm 0.25\\pm 0.04\\right)\\times {10}^{-3},\\\\ {}\\frac{{\\mathcal{B}}_{\\mathrm{B}+\\to {\\upchi}_{\\mathrm{c}1}(3872){\\mathrm{K}}^{+}}\\times {\\mathcal{B}}_{\\upchi_{\\mathrm{c}1}(3872)\\to \\mathrm{J}/{\\uppsi \\uppi}^{+}{\\uppi}^{-}}}{{\\mathcal{B}}_{{\\mathrm{B}}^{+}\\to \\uppsi \\left(2\\mathrm{S}\\right){\\mathrm{K}}^{+}}\\times {\\mathcal{B}}_{\\uppsi \\left(2\\mathrm{S}\\right)\\to \\mathrm{J}/{\\uppsi \\uppi}^{+}{\\uppi}^{-}}}=\\left(3.69\\pm 0.07\\pm 0.06\\right)\\times {10}^{-2},\\end{array}} $$ B B + → ψ 2 3823 K + × B ψ 2 3823 → J / ψπ + π − B B + → χ c 1 3872 K + × B χ c 1 3872 → J / ψπ + π − = 3.56 ± 0.67 ± 0.11 × 10 − 2 , B B + → ψ 2 3823 K + × B ψ 2 3823 → J / ψπ + π − B B + → ψ 2 S K + × B ψ 2 S → J / ψπ + π − = 1.31 ± 0.25 ± 0.04 × 10 − 3 , B B + → χ c 1 3872 K + × B χ c 1 3872 → J / ψπ + π − B B + → ψ 2 S K + × B ψ 2 S → J / ψπ + π − = 3.69 ± 0.07 ± 0.06 × 10 − 2 , where the first uncertainty is statistical and the second is systematic. The decay of B + → ψ 2 (3823)K + with ψ 2 (3823) → J / ψπ + π − is observed for the first time with a significance of 5.1 standard deviations. The mass differences between the ψ 2 (3823), χ c1 (3872) and ψ(2S) states are measured to be $$ {\\displaystyle \\begin{array}{c}{m}_{\\upchi_{\\mathrm{c}1}(3872)}-{m}_{\\uppsi_2(3823)}=47.50\\pm 0.53\\pm 0.13\\ \\mathrm{MeV}/{c}^2,\\\\ {}{m}_{\\uppsi_2(3823)}-{m}_{\\uppsi_2\\left(2\\mathrm{S}\\right)}=137.98\\pm 0.53\\pm 0.14\\ \\mathrm{MeV}/{c}^2,\\\\ {}{m}_{\\upchi_{\\mathrm{c}1}(3872)}-{m}_{\\uppsi_2\\left(2\\mathrm{S}\\right)}=185.49\\pm 0.06\\pm 0.03\\ \\mathrm{MeV}/{c}^2,\\end{array}} $$ m χ c 1 3872 − m ψ 2 3823 = 47.50 ± 0.53 ± 0.13 MeV / c 2 , m ψ 2 3823 − m ψ 2 2 S = 137.98 ± 0.53 ± 0.14 MeV / c 2 , m χ c 1 3872 − m ψ 2 2 S = 185.49 ± 0.06 ± 0.03 MeV / c 2 , resulting in the most precise determination of the χ c1 (3872) mass. The width of the ψ 2 (3823) state is found to be below 5.2 MeV at 90% confidence level. The Breit-Wigner width of the χ c1 (3872) state is measured to be $$ {\\Gamma}_{\\upchi_{\\mathrm{c}1}(3872)}^{\\mathrm{BW}}={0.96}_{-0.18}^{+0.19}\\pm 0.21\\ \\mathrm{MeV} $$ Γ χ c 1 3872 BW = 0.96 − 0.18 + 0.19 ± 0.21 MeV which is inconsistent with zero by 5.5 standard deviations.
Publisher: Elsevier BV
Date: 02-2021
Publisher: Elsevier BV
Date: 11-2016
Publisher: American Physical Society (APS)
Date: 02-03-2021
Publisher: American Physical Society (APS)
Date: 26-03-2021
Publisher: Elsevier BV
Date: 10-1998
Publisher: American Physical Society (APS)
Date: 27-08-2021
Publisher: Elsevier BV
Date: 2022
Publisher: Springer Science and Business Media LLC
Date: 2022
DOI: 10.1038/S41567-021-01394-X
Abstract: Mesons comprising a beauty quark and strange quark can oscillate between particle ( $${B}_{\\mathrm{s}}^{0}$$ B s 0 ) and antiparticle ( $${\\overline{B}}_{\\mathrm{s}}^{0}$$ B ¯ s 0 ) flavour eigenstates, with a frequency given by the mass difference between heavy and light mass eigenstates, Δ m s . Here we present a measurement of Δ m s using $${B}_{\\mathrm{s}}^{0}\\to {D}_{\\mathrm{s}}^{-}$$ B s 0 → D s − π + decays produced in proton–proton collisions collected with the LHCb detector at the Large Hadron Collider. The oscillation frequency is found to be Δ m s = 17.7683 ± 0.0051 ± 0.0032 ps −1 , where the first uncertainty is statistical and the second is systematic. This measurement improves on the current Δ m s precision by a factor of two. We combine this result with previous LHCb measurements to determine Δ m s = 17.7656 ± 0.0057 ps −1 , which is the legacy measurement of the original LHCb detector.
Publisher: Springer Science and Business Media LLC
Date: 11-2021
Abstract: The production cross-sections of J/ψ mesons in proton-proton collisions at a centre-of-mass energy of $$ \\sqrt{s} $$ s = 5 TeV are measured using a data s le corresponding to an integrated luminosity of 9 . 13 ± 0 . 18 pb − 1 , collected by the LHCb experiment. The cross-sections are measured differentially as a function of transverse momentum, p T , and rapidity, y , and separately for J/ψ mesons produced promptly and from beauty hadron decays (nonprompt). With the assumption of unpolarised J/ψ mesons, the production cross-sections integrated over the kinematic range 0 p T 20 GeV/ c and 2 . 0 y 4 . 5 are $$ {\\displaystyle \\begin{array}{c}{\\sigma}_{\\mathrm{prompt}}\\ J/\\psi =8.154\\pm 0.010\\pm 0.283\\ \\upmu \\mathrm{b},\\\\ {}{\\sigma}_{\\mathrm{nonprompt}}\\ J/\\psi =0.820\\pm 0.003\\pm 0.034\\ \\upmu \\mathrm{b},\\end{array}} $$ σ prompt J / ψ = 8.154 ± 0.010 ± 0.283 μb , σ nonprompt J / ψ = 0.820 ± 0.003 ± 0.034 μb , where the first uncertainties are statistical and the second systematic. These cross-sections are compared with those at $$ \\sqrt{s} $$ s = 8 TeV and 13 TeV, and are used to update the measurement of the nuclear modification factor in proton-lead collisions for J/ψ mesons at a centre-of-mass energy per nucleon pair of $$ \\sqrt{s_{\\mathrm{NN}}} $$ s NN = 5 TeV. The results are compared with theoretical predictions.
Publisher: Elsevier BV
Date: 02-2003
Publisher: American Physical Society (APS)
Date: 22-12-2020
Publisher: Wiley
Date: 17-01-2014
DOI: 10.1111/BRE.12045
Publisher: Springer Science and Business Media LLC
Date: 10-06-2016
DOI: 10.1038/NCOMMS11834
Abstract: Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a ‘perennial’ phenomenon.
Publisher: American Physical Society (APS)
Date: 18-12-2020
Publisher: Elsevier BV
Date: 10-2017
Publisher: Elsevier BV
Date: 07-2020
Publisher: Geological Society of London
Date: 2006
Publisher: Elsevier BV
Date: 07-2020
Publisher: Elsevier BV
Date: 02-2020
Publisher: Geological Society of London
Date: 2006
Publisher: Geological Society of London
Date: 11-01-2024
DOI: 10.1144/M57-2021-19
Abstract: The Canadian Arctic Prograded Margin Tectono-Stratigraphic Element (TSE) is located on the continental shelf and slope, which lie to the NW of the Canadian Arctic Archipelago. The TSE comprises a post-rift succession deposited on the eastern margin of the Amerasia Basin, and the strata range in age from Late Cretaceous to Pleistocene. Over much of the TSE, a major unconformity marks the base of the succession, and the underlying strata vary from Jurassic to Lower Cretaceous strata of the Canadian Arctic Rift Margin TSE to older Upper Paleozoic–Triassic strata of the Sverdrup Basin Composite Tectono-Sedimentary Element. Sparse reflection and refraction seismic data indicate that the succession can be more than 10 km thick. The TSE is ided into three structural domains with deformation increasing to the NE. The Southern Domain is extensional and is characterized by listric growth faults with rollover anticlines and tilted fault blocks. The pre-Oligocene portion of the Central Domain is deformed by broad folds with extensional faults in the younger strata. The pre-Oligocene succession in the Northern Domain is likely to be strongly folded and cut by thrust faults of the Eurekan Orogeny with extrusive and intrusive igneous rocks occurring in the Upper Cretaceous strata. Petroleum source rocks, as well as abundant reservoir and seal strata, occur throughout the TSE, indicating good potential for the presence of petroleum resources. The remote and environmentally sensitive location of the TSE, however, makes it likely that it will never be a target for petroleum exploration.
Publisher: Geological Society of London
Date: 03-2018
DOI: 10.1144/SP470.7
Publisher: Elsevier BV
Date: 07-1993
Publisher: American Physical Society (APS)
Date: 25-01-2022
Publisher: American Association for the Advancement of Science (AAAS)
Date: 13-08-2010
Abstract: Changing sea level or major tectonic events, such as continental collisions, shift stratigraphic sequences by changing the depositional environment where certain rock types form. For ex le, a deep marine environment where limestone formation is favored may shift relatively quickly to a near-shore environment favoring sandstone formation because the relative sea level has dropped several meters. Petersen et al. (p. 827 see the Perspective by Müller ), however, suggest that small-scale convection in the mantle may also induce appreciable changes in the sequence of sedimentary deposits. Using a modeling approach, they found that this is possible on a small scale (that is, just a few hundreds of kilometers) over variable time scales. Thus, while the co-occurrence of sedimentary deposit sequences at regional and global scales can allow sedimentary rocks to serve as markers of marine environments, it should be kept in mind that local changes in surface movements may also manifest themselves in the rock record.
Publisher: Springer Science and Business Media LLC
Date: 12-2020
Abstract: An angular analysis of the B 0 → K* 0 e + e − decay is performed using a data s le 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 GeV 2 , where the rate is dominated by the B 0 → K * 0 γ transition with a virtual photon. The fraction of longitudinal polarisation of the K * 0 meson, F L , is measured to be F L = (4 . 4 ± 2 . 6 ± 1 . 4)%, where the first uncertainty is statistical and the second systematic. The $$ {A}_{\\mathrm{T}}^{\\mathrm{Re}} $$ A T Re observable, which is related to the lepton forward-backward asymmetry, is measured to be $$ {A}_{\\mathrm{T}}^{\\mathrm{Re}} $$ A T Re = − 0 . 06 ± 0 . 08 ± 0 . 02. The $$ {A}_{\\mathrm{T}}^{(2)} $$ A T 2 and $$ {A}_{\\mathrm{T}}^{\\mathrm{Im}} $$ A T Im transverse asymmetries, which are sensitive to the virtual photon polarisation, are found to be $$ {A}_{\\mathrm{T}}^{(2)} $$ A T 2 = 0 . 11 ± 0 . 10 ± 0 . 02 and $$ {A}_{\\mathrm{T}}^{\\mathrm{Im}} $$ A T Im = 0 . 02 ± 0 . 10 ± 0 . 01. The results are consistent with Standard Model predictions and provide the world’s best constraint on the b → sγ photon polarisation.
Publisher: Elsevier BV
Date: 08-2006
Publisher: Elsevier BV
Date: 2024
Publisher: American Physical Society (APS)
Date: 05-10-2021
Publisher: Elsevier BV
Date: 12-2000
Publisher: Geological Society of London
Date: 09-2012
Publisher: Elsevier BV
Date: 2009
Publisher: Wiley
Date: 17-12-2011
Publisher: Springer Science and Business Media LLC
Date: 07-1995
DOI: 10.1007/BF02295821
Publisher: Springer Science and Business Media LLC
Date: 06-1992
DOI: 10.1007/BF02084914
Publisher: Springer Science and Business Media LLC
Date: 06-2021
Abstract: A search is performed for rare and forbidden charm decays of the form $$ {D}_{(s)}^{+}\\to {h}^{\\pm }{\\mathrm{\\ell}}^{+}{\\mathrm{\\ell}}^{\\left(\\prime \\right)\\mp } $$ D s + → h ± ℓ + ℓ ′ ∓ , where h ± is a pion or kaon and ℓ (′)± is an electron or muon. The measurements are performed using proton-proton collision data, corresponding to an integrated luminosity of 1 . 6 fb − 1 , collected by the LHCb experiment in 2016. No evidence is observed for the 25 decay modes that are investigated and 90 % confidence level limits on the branching fractions are set between 1 . 4 × 10 − 8 and 6 . 4 × 10 − 6 . In most cases, these results represent an improvement on existing limits by one to two orders of magnitude.
Publisher: Springer Science and Business Media LLC
Date: 30-01-2017
DOI: 10.1038/NPHYS4021
Publisher: Elsevier BV
Date: 03-2004
Publisher: Elsevier BV
Date: 10-2023
Publisher: Elsevier BV
Date: 10-2010
Publisher: MDPI AG
Date: 28-10-2021
DOI: 10.3390/RS13214345
Abstract: A new phase-based filter (called improved analytical signal (IAS)) is introduced to detect buried unexploded ordnance (UXO) precisely from magnetic fields using the arcsine function of the ratio of the first-order vertical derivative of the analytical signal to the first-order derivatives of the x-, y-, and z-components of the analytical signal. The calculations are computed in the frequency domain and then transformed back into the space domain using the inverse Fourier transform. The filter has been tested on magnetic data collected at a test site with UXO bodies of variable orientation. It was also validated on magnetic data measured at a former army artillery range in Slovakia. The results show that the IAS filter not only revealed better imaging of the UXO bodies compared to the other commonly used filters but also produced a high-resolution image with much less influence of noise.
Publisher: Geological Society of America
Date: 04-2014
DOI: 10.1130/G35244.1
Publisher: Elsevier BV
Date: 12-2020
Publisher: Geological Society of America
Date: 31-12-2018
DOI: 10.1130/G45690.1
Publisher: Springer Science and Business Media LLC
Date: 03-2021
DOI: 10.1140/EPJC/S10052-021-08973-5
Abstract: A search is performed for heavy neutrinos in the decay of a W boson into two muons and a jet. The data set corresponds to an integrated luminosity of approximately $$3.0\\, \\text {fb} ^{-1} $$ 3.0 fb - 1 of proton–proton collision data at centre-of-mass energies of 7 and $$8\\, \\text {TeV} $$ 8 TeV collected with the LHCb experiment. Both same-sign and opposite-sign muons in the final state are considered. Data are found to be consistent with the expected background. Upper limits on the coupling of a heavy neutrino with the Standard Model neutrino are set at $$95\\%$$ 95 % confidence level in the heavy-neutrino mass range from 5 to $$50\\, \\text {GeV/}c^2 $$ 50 GeV/ c 2 . These are of the order of $$10^{-3}$$ 10 - 3 for lepton-number-conserving decays and of the order of $$10^{-4}$$ 10 - 4 for lepton-number-violating heavy-neutrino decays.
Publisher: American Physical Society (APS)
Date: 09-06-2021
Publisher: Informa UK Limited
Date: 06-1986
Publisher: American Geophysical Union (AGU)
Date: 08-2010
DOI: 10.1029/2009TC002620
Publisher: Oxford University Press (OUP)
Date: 07-1985
Publisher: Elsevier BV
Date: 09-2003
Publisher: Geological Society of London
Date: 2010
DOI: 10.1144/SP340.8
Publisher: Geological Society of America
Date: 2007
Publisher: Elsevier
Date: 2012
Publisher: Elsevier BV
Date: 2016
Publisher: Springer Science and Business Media LLC
Date: 12-2007
DOI: 10.1038/NATURE06379
Abstract: The process of continental break-up provides a large-scale experiment that can be used to test causal relations between plate tectonics and the dynamics of the Earth's deep mantle. Detailed diagnostic information on the timing and dynamics of such events, which are not resolved by plate kinematic reconstructions, can be obtained from the response of the interior of adjacent continental plates to stress changes generated by plate boundary processes. Here we demonstrate a causal relationship between North Atlantic continental rifting at approximately 62 Myr ago and an abrupt change of the intra-plate deformation style in the adjacent European continent. The rifting involved a left-lateral displacement between the North American-Greenland plate and Eurasia, which initiated the observed pause in the relative convergence of Europe and Africa. The associated stress change in the European continent was significant and explains the sudden termination of a approximately 20-Myr-long contractional intra-plate deformation within Europe, during the late Cretaceous period to the earliest Palaeocene epoch, which was replaced by low- litude intra-plate stress-relaxation features. The pre-rupture tectonic stress was large enough to have been responsible for precipitating continental break-up, so there is no need to invoke a thermal mantle plume as a driving mechanism. The model explains the simultaneous timing of several erse geological events, and shows how the intra-continental stratigraphic record can reveal the timing and dynamics of stress changes, which cannot be resolved by reconstructions based only on plate kinematics.
Publisher: Elsevier BV
Date: 08-2003
Publisher: Elsevier BV
Date: 11-2013
Publisher: Geological Society of London
Date: 2010
DOI: 10.1144/SP340.2
Publisher: Elsevier BV
Date: 02-2002
Publisher: Geological Society of London
Date: 2010
DOI: 10.1144/SP340.1
Publisher: Elsevier BV
Date: 12-2010
Publisher: Springer Science and Business Media LLC
Date: 03-2021
Abstract: The time-dependent CP asymmetries of B 0 → π + π − and $$ {B}_s^0 $$ B s 0 → K + K − decays are measured using a data s le of pp collisions corresponding to an integrated luminosity of 1.9 fb − 1 , collected with the LHCb detector at a centre-of-mass energy of 13 TeV. The results are $$ {\\displaystyle \\begin{array}{c}{C}_{\\pi \\pi}=-0.311\\pm 0.045\\pm 0.015,\\\\ {}{S}_{\\pi \\pi}=-0.706\\pm 0.042\\pm 0.013,\\\\ {}{C}_{KK}=0.123\\pm 0.034\\pm 0.015,\\\\ {}{S}_{KK}=0.164\\pm 0.034\\pm 0.014,\\\\ {}{\\mathcal{A}}_{KK}^{\\Delta \\varGamma }=-0.83\\pm 0.05\\pm 0.09,\\end{array}} $$ C ππ = − 0.311 ± 0.045 ± 0.015 , S ππ = − 0.706 ± 0.042 ± 0.013 , C KK = 0.123 ± 0.034 ± 0.015 , S KK = 0.164 ± 0.034 ± 0.014 , A KK Δ Γ = − 0.83 ± 0.05 ± 0.09 , where the first uncertainties are statistical and the second systematic. The same data s le is used to measure the time-integrated CP asymmetries of B 0 → K + π − and $$ {B}_s^0 $$ B s 0 → K − π + decays and the results are $$ {\\displaystyle \\begin{array}{c}{A}_{CP}^{B^0}=-0.0824\\pm 0.0033\\pm 0.0033,\\\\ {}{A}_{CP}^{B_s^0}=0.236\\pm 0.013\\pm 0.011.\\end{array}} $$ A CP B 0 = − 0.0824 ± 0.0033 ± 0.0033 , A CP B s 0 = 0.236 ± 0.013 ± 0.011 . All results are consistent with earlier measurements. A combination of LHCb measurements provides the first observation of time-dependent CP violation in $$ {B}_s^0 $$ B s 0 decays.
Publisher: American Physical Society (APS)
Date: 02-12-2020
Publisher: Geological Society of London
Date: 27-10-2017
DOI: 10.1144/SP428.2
Publisher: Geological Society of London
Date: 2006
Publisher: Springer Science and Business Media LLC
Date: 06-2021
Abstract: The first full angular analysis of the $$ {B}^0\\to {D}^{\\ast -}{D}_s^{\\ast +} $$ B 0 → D ∗ − D s ∗ + decay is performed using 6 fb − 1 of pp collision data collected with the LHCb experiment at a centre-of-mass energy of 13 TeV. The $$ {D}_s^{\\ast +}\\to {D}_s^{+}\\gamma $$ D s ∗ + → D s + γ and D * − → $$ {\\overline{D}}^0{\\pi}^{-} $$ D ¯ 0 π − vector meson decays are used with the subsequent $$ {D}_s^{+} $$ D s + → K + K − π + and $$ {\\overline{D}}^0 $$ D ¯ 0 → K + π − decays. All helicity litudes and phases are measured, and the longitudinal polarisation fraction is determined to be f L = 0 . 578 ± 0 . 010 ± 0 . 011 with world-best precision, where the first uncertainty is statistical and the second is systematic. The pattern of helicity litude magnitudes is found to align with expectations from quark-helicity conservation in B decays. The ratio of branching fractions [ℬ( $$ {B}^0\\to {D}^{\\ast -}{D}_s^{\\ast +} $$ B 0 → D ∗ − D s ∗ + ) × ℬ( $$ {D}_s^{\\ast +}\\to {D}_s^{+}\\gamma $$ D s ∗ + → D s + γ )] / ℬ( B 0 → D * − $$ {D}_s^{+} $$ D s + ) is measured to be 2 . 045 ± 0 . 022 ± 0 . 071 with world-best precision. In addition, the first observation of the Cabibbo-suppressed B s → D * − $$ {D}_s^{+} $$ D s + decay is made with a significance of seven standard deviations. The branching fraction ratio ℬ( B s → D * − $$ {D}_s^{+} $$ D s + ) / ℬ( B 0 → D * − $$ {D}_s^{+} $$ D s + ) is measured to be 0 . 049 ± 0 . 006 ± 0 . 003 ± 0 . 002, where the third uncertainty is due to limited knowledge of the ratio of fragmentation fractions.
Publisher: American Physical Society (APS)
Date: 31-07-2020
Publisher: Elsevier BV
Date: 12-1995
Publisher: No publisher found
Date: 2017
DOI: 10.1103/PHYSREVLETT.118.021801, 10.1103/PHYSREVLETT.118.109901
Publisher: Springer Science and Business Media LLC
Date: 12-2020
Abstract: The shape of the $$ {B}_s^0\\to {D}_s^{\\ast -}{\\mu}^{+}{\\nu}_{\\mu } $$ B s 0 → D s ∗ − μ + ν μ differential decay rate is obtained as a function of the hadron recoil parameter using proton-proton collision data at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.7 fb − 1 collected by the LHCb detector. The $$ {B}_s^0\\to {D}_s^{\\ast -}{\\mu}^{+}{\\nu}_{\\mu } $$ B s 0 → D s ∗ − μ + ν μ decay is reconstructed through the decays $$ {D}_s^{\\ast -}\\to {D}_s^{-}\\gamma $$ D s ∗ − → D s − γ and $$ {D}_s^{-}\\to {K}^{-}{K}^{+}{\\pi}^{-} $$ D s − → K − K + π − . The differential decay rate is fitted with the Caprini-Lellouch-Neubert (CLN) and Boyd-Grinstein-Lebed (BGL) parametrisations of the form factors, and the relevant quantities for both are extracted.
Publisher: American Geophysical Union (AGU)
Date: 12-1985
Publisher: Elsevier BV
Date: 07-2003
Publisher: Springer Science and Business Media LLC
Date: 11-2020
Abstract: A search for the doubly heavy $$ {\\Xi}_{bc}^0 $$ Ξ bc 0 baryon using its decay to the D 0 pK – final state is performed using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the LHCb experiment between 2016 and 2018, corresponding to an integrated luminosity of 5.4 fb − 1 . No significant signal is found in the invariant mass range from 6.7 to 7.2 GeV/ c 2 . Upper limits are set at 95% credibility level on the ratio of the $$ {\\Xi}_{bc}^0 $$ Ξ bc 0 production cross-section times its branching fraction to D 0 pK − relative to that of the $$ {\\Lambda}_b^0\\to {D}^0{pK}^{-} $$ Λ b 0 → D 0 pK − decay. The limits are set as a function of the $$ {\\Xi}_{bc}^0 $$ Ξ bc 0 mass and lifetime hypotheses, in the rapidity range from 2.0 to 4.5 and in the transverse momentum region from 5 to 25 GeV/ c . Upper limits range from 1 . 7 × 10 − 2 to 3 . 0 × 10 − 1 for the considered $$ {\\Xi}_{bc}^0 $$ Ξ bc 0 mass and lifetime hypotheses.
Publisher: Elsevier BV
Date: 07-1992
Publisher: Elsevier BV
Date: 12-2002
Publisher: American Physical Society (APS)
Date: 24-11-2021
Publisher: IOP Publishing
Date: 04-2021
Abstract: A search for the rare decay is performed using collision data collected with the LHCb dete-ctor at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb −1 . No significant signal of the decay is observed and an upper limit of at 90% confidence level is set on the branching fraction.
Publisher: Elsevier BV
Date: 11-2016
Publisher: Elsevier BV
Date: 11-2014
Publisher: Elsevier BV
Date: 11-2013
Publisher: Informa UK Limited
Date: 12-2003
Publisher: Elsevier BV
Date: 11-1999
Publisher: American Physical Society (APS)
Date: 07-09-2021
Publisher: American Physical Society (APS)
Date: 08-09-2020
Publisher: IGI Global
Date: 2007
DOI: 10.4018/978-1-59904-304-3.CH015
Abstract: simSchool is a game-based simulation developed with funding from the Preparing Tomorrow’s Teachers to Use Technology (PT3, 2003) program of the United States Department of Education. The simulation provides users with a training environment for developing skills such as lesson planning, differentiating instruction, classroom management, special education, and adapting teaching to multiple cognitive abilities. This chapter uses simSchool as an ex le to present and discuss an application of the Conceptual Assessment Framework (CAF) of (Almond, Steinberg, & Mislevy, 2002) as a general model for building assessments of what users learn through games and simulations. The CAF organizes the theories of teaching as well as the inferential frameworks in simSchool that are used to provide feedback to players about their levels of knowledge and abilities as teachers. The framework is generally relevant and useful for planning how to assess gains made by users while playing games or using simulations.
Publisher: Springer Science and Business Media LLC
Date: 05-2021
Abstract: The Cabibbo-suppressed decay $$ {\\Lambda}_{\\mathrm{b}}^0 $$ Λ b 0 → χ c1 pπ − is observed for the first time using data from proton-proton collisions corresponding to an integrated luminosity of 6 fb − 1 , collected with the LHCb detector at a centre-of-mass energy of 13 TeV. Evidence for the $$ {\\Lambda}_{\\mathrm{b}}^0 $$ Λ b 0 → χ c2 pπ − decay is also found. Using the $$ {\\Lambda}_{\\mathrm{b}}^0 $$ Λ b 0 → χ c1 pK − decay as normalisation channel, the ratios of branching fractions are measured to be $$ {\\displaystyle \\begin{array}{c}\\frac{\\mathcal{B}\\left({\\Lambda}_{\\mathrm{b}}^0\\to {\\upchi}_{\\mathrm{c}1}{\\mathrm{p}\\uppi}^{-}\\right)}{\\mathcal{B}\\left({\\Lambda}_{\\mathrm{b}}^0\\to {\\upchi}_{\\mathrm{c}1}{\\mathrm{p}\\mathrm{K}}^{-}\\right)}=\\left(6.59\\pm 1.01\\pm 0.22\\right)\\times {10}^{-2},\\\\ {}\\frac{\\mathcal{B}\\left({\\Lambda}_{\\mathrm{b}}^0\\to {\\upchi}_{\\mathrm{c}2}{\\mathrm{p}\\uppi}^{-}\\right)}{\\mathcal{B}\\left({\\Lambda}_{\\mathrm{b}}^0\\to {\\upchi}_{\\mathrm{c}1}{\\mathrm{p}\\uppi}^{-}\\right)}=0.95\\pm 0.30\\pm 0.04\\pm 0.04,\\\\ {}\\frac{\\mathcal{B}\\left({\\Lambda}_{\\mathrm{b}}^0\\to {\\upchi}_{\\mathrm{c}2}{\\mathrm{p}\\mathrm{K}}^{-}\\right)}{\\mathcal{B}\\left({\\Lambda}_{\\mathrm{b}}^0\\to {\\upchi}_{\\mathrm{c}1}{\\mathrm{p}\\mathrm{K}}^{-}\\right)}=1.06\\pm 0.05\\pm 0.04\\pm 0.04,\\end{array}} $$ B Λ b 0 → χ c 1 pπ − B Λ b 0 → χ c 1 pK − = 6.59 ± 1.01 ± 0.22 × 10 − 2 , B Λ b 0 → χ c 2 pπ − B Λ b 0 → χ c 1 pπ − = 0.95 ± 0.30 ± 0.04 ± 0.04 , B Λ b 0 → χ c 2 pK − B Λ b 0 → χ c 1 pK − = 1.06 ± 0.05 ± 0.04 ± 0.04 , where the first uncertainty is statistical, the second is systematic and the third is due to the uncertainties in the branching fractions of χ c1 , 2 → J / ψγ decays.
Publisher: American Physical Society (APS)
Date: 25-02-2021
Publisher: Springer Science and Business Media LLC
Date: 10-2020
Abstract: Searches are performed for a low-mass dimuon resonance, X , produced in proton-proton collisions at a center-of-mass energy of 13 TeV, using a data s le corresponding to an integrated luminosity of 5.1 fb − 1 and collected with the LHCb detector. The X bosons can either decay promptly or displaced from the proton-proton collision, where in both cases the requirements placed on the event and the assumptions made about the production mechanisms are kept as minimal as possible. The searches for promptly decaying X bosons explore the mass range from near the dimuon threshold up to 60 GeV, with nonnegligible X widths considered above 20 GeV. The searches for displaced X → μ + μ − decays consider masses up to 3 GeV. None of the searches finds evidence for a signal and 90% confidence-level exclusion limits are placed on the X → μ + μ − cross sections, each with minimal model dependence. In addition, these results are used to place world-leading constraints on GeV-scale bosons in the two-Higgs-doublet and hidden-valley scenarios.
Publisher: American Geophysical Union (AGU)
Date: 10-2003
DOI: 10.1029/2002TC001366
Publisher: American Physical Society (APS)
Date: 04-06-2020
Publisher: Springer Science and Business Media LLC
Date: 04-2021
Abstract: Measurements of CP observables in B ± → D (*) K ± and B ± → D (*) π ± decays are presented, where D (∗) indicates a neutral D or D ∗ meson that is an admixture of meson and anti-meson states. Decays of the D (∗) meson to the Dπ 0 and Dγ final states are partially reconstructed without inclusion of the neutral pion or photon. Decays of the D meson are reconstructed in the K ± π ∓ , K + K − , and π + π − final states. The analysis uses a s le of charged B mesons produced in proton-proton collisions and collected with the LHCb experiment, corresponding to integrated luminosities of 2.0, 1.0, and 5.7 fb − 1 taken at centre-of-mass energies of 7, 8, and 13 TeV, respectively. The measurements of partially reconstructed B ± → D (*) K ± and B ± → D (∗) π ± with D → K ∓ π ± decays are the first of their kind, and a first observation of the B ± → $$ {\\left(D{\\pi}^0\\right)}_{D^{\\ast }}{\\pi}^{\\pm } $$ D π 0 D ∗ π ± decay is made with a significance of 6.1 standard deviations. All CP observables are measured with world-best precision, and in combination with other LHCb results will provide strong constraints on the CKM angle γ .
Publisher: American Geophysical Union (AGU)
Date: 04-09-2004
DOI: 10.1029/2003TC001582
Publisher: Elsevier BV
Date: 12-2005
Publisher: Geological Society of London
Date: 03-02-2016
DOI: 10.1144/SP428.11
Publisher: Geological Society of London
Date: 12-09-2013
DOI: 10.1144/JGS2012-146
Publisher: Elsevier BV
Date: 02-2002
Publisher: Canadian Society of Petroleum Geologists
Date: 12-2014
Publisher: Geological Society of London
Date: 23-05-2016
DOI: 10.1144/SP428.15
Publisher: Elsevier BV
Date: 02-2019
Publisher: Geological Society of London
Date: 2017
DOI: 10.1144/SP428.16
Publisher: IOP Publishing
Date: 09-2021
Abstract: The first search for the doubly heavy baryon and a search for the baryon are performed using collision data collected via the experiment from 2016 to 2018 at a centre-of-mass energy of , corresponding to an integrated luminosity of 5.2 . The baryons are reconstructed via their decays to and . No significant excess is found for invariant masses between 6700 and 7300 , in a rapidity range from 2.0 to 4.5 and a transverse momentum range from 2 to 20 . Upper limits are set on the ratio of the and production cross-section times the branching fraction to ( ) relative to that of the ( ) baryon, for different lifetime hypotheses, at 95% confidence level. The upper limits range from to for the ( ) decay, and from to for the ( ) decay, depending on the considered mass and lifetime of the ( ) baryon.
Publisher: American Physical Society (APS)
Date: 06-01-2021
Publisher: Oxford University Press (OUP)
Date: 06-2008
Publisher: Oxford University Press (OUP)
Date: 16-05-2019
DOI: 10.1093/GJI/GGZ227
Publisher: Geological Society of London
Date: 12-06-2017
DOI: 10.1144/SP460.8
Publisher: Elsevier BV
Date: 11-2016
Publisher: Springer Science and Business Media LLC
Date: 31-08-2021
DOI: 10.1007/S11433-021-1742-7
Abstract: A search for the doubly charmed baryon Ω cc + with the decay mode Ω cc + → Ξ c + K − π + is performed using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4 fb −1 . No significant signal is observed within the invariant mass range of 3.6 to 4.0GeV/ c 2 . Upper limits are set on the ratio R of the production cross-section times the total branching fraction of the Ω cc + → Ξ c + K − π + decay with respect to the $$\\Xi _{cc}^{ + + } \\to \\Lambda _c^ + {K^ - }{\\pi ^ + }{\\pi ^ + }$$ Ξ c c + + → Λ c + K − π + π + decay. Upper limits at 95% credibility level for R in the range 0.005 to 0.11 are obtained for different hypotheses on the Ω cc + mass and lifetime in the rapidity range from 2.0 to 4.5 and transverse momentum range from 4 to 15 GeV/ c .
Publisher: No publisher found
Date: 2019
Publisher: American Physical Society (APS)
Date: 07-12-2020
Publisher: Elsevier BV
Date: 11-2015
Publisher: Oxford University Press (OUP)
Date: 28-01-2016
DOI: 10.1093/GJI/GGV539
Publisher: Geological Society of America
Date: 2003
DOI: 10.1130/G19329.1
Publisher: American Physical Society (APS)
Date: 26-10-2021
Publisher: Springer Science and Business Media LLC
Date: 03-2021
Abstract: The CKM angle γ is measured for the first time from mixing-induced CP violation between $$ {B}_s^0\\to {D}_s^{\\mp }{K}^{\\pm }{\\pi}^{\\pm }{\\pi}^{\\mp } $$ B s 0 → D s ∓ K ± π ± π ∓ and $$ {\\overline{B}}_s^0\\to {D}_s^{\\pm }{K}^{\\mp }{\\pi}^{\\mp }{\\pi}^{\\pm } $$ B ¯ s 0 → D s ± K ∓ π ∓ π ± decays reconstructed in proton-proton collision data corresponding to an integrated luminosity of 9 fb − 1 recorded with the LHCb detector. A time-dependent litude analysis is performed to extract the CP -violating weak phase γ − 2 β s and, subsequently, γ by taking the $$ {B}_s^0\\hbox{-} {\\overline{B}}_s^0 $$ B s 0 ‐ B ¯ s 0 mixing phase β s as an external input. The measurement yields γ = (44 ± 12)° modulo 180°, where statistical and systematic uncertainties are combined. An alternative model-independent measurement, integrating over the five-dimensional phase space of the decay, yields $$ \\gamma =\\left({44}_{-13}^{+20}\\right){}^{\\circ} $$ γ = 44 − 13 + 20 ° modulo 180°. Moreover, the $$ {B}_s^0\\hbox{-} {\\overline{B}}_s^0 $$ B s 0 ‐ B ¯ s 0 oscillation frequency is measured from the flavour-specific control channel $$ {B}_s^0\\to {D}_s^{-}{\\pi}^{+}{\\pi}^{+}{\\pi}^{-} $$ B s 0 → D s − π + π + π − to be ∆ m s = (17 . 757 ± 0 . 007(stat) ± 0 . 008(syst)) ps − 1 , consistent with and more precise than the current world-average value.
Publisher: Springer Science and Business Media LLC
Date: 12-2021
Abstract: A data set corresponding to an integrated luminosity of 9 fb − 1 of proton-proton collisions collected by the LHCb experiment has been analysed to search for $$ {B}_c^{+}\\to {D}_{(s)}^{\\left(\\ast \\right)+}{\\genfrac{}{}{0pt}{}{\\left(\\hbox{---} \\right)}{D}}^{\\left(\\ast \\right)0} $$ B c + → D s ∗ + — D ∗ 0 decays. The decays are fully or partially reconstructed, where one or two missing neutral pions or photons from the decay of an excited charm meson are allowed. Upper limits for the branching fractions, normalised to B + decays to final states with similar topologies, are obtained for sixteen $$ {B}_c^{+} $$ B c + decay modes. For the decay $$ {B}_c^{+}\\to {D}_s^{+}{\\overline{D}}^0 $$ B c + → D s + D ¯ 0 , an excess with a significance of 3.4 standard deviations is found.
Publisher: Geological Society of London
Date: 23-07-2019
DOI: 10.1144/JGS2018-211
Publisher: Springer Science and Business Media LLC
Date: 03-2021
Abstract: A search for the $$ {B}_{\\mathrm{s}}^0 $$ B s 0 → D *± D ∓ decay is performed using proton-proton collision data at centre-of-mass energies of 7, 8 and 13 TeV collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb − 1 . The decay is observed with a high significance and its branching fraction relative to the B 0 → D *± D ∓ decay is measured to be $$ \\frac{\\mathrm{\\mathcal{B}}\\left({B}_s^0\\to {D}^{\\ast \\pm }{D}^{\\mp}\\right)}{\\left({B}^0\\to {D}^{\\ast \\pm }{D}^{\\mp}\\right)}=0.137\\pm 0.017\\pm 0.002\\pm 0.006, $$ ℬ B s 0 → D ∗ ± D ∓ B 0 → D ∗ ± D ∓ = 0.137 ± 0.017 ± 0.002 ± 0.006 , where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the ratio of the $$ {B}_{\\mathrm{s}}^0 $$ B s 0 and B 0 hadronisation fractions.
Publisher: Copernicus GmbH
Date: 08-04-2020
DOI: 10.5194/EGUSPHERE-EGU2020-409
Abstract: & & During the Mesozoic, the relative movement of African and Eurasian plates caused the opening of the Tethys Ocean. The rifting phase is well charted by the stratigraphic sequence of Western Alps, which provide an exceptional record of continental margin evolution. The Brian& #231 onnais domain occupies a pivotal place for testing various rifting models. This domain contains a remarkably uniform succession of very shallow-water carbonates of Triassic age, capped by Middle-Jurassic shallow-water carbonates or by non-deposition before passing abruptly up into deep-water facies. Here we show that the back-stripped Mesozoic tectonic evolution of the Brian& #231 onnais block can be applied to investigate models of lithospheric stretching. Applying the Airy correction, we found that the Triassic is characterised by a constant tectonic subsidence rate of 17 m/Ma. If this is the result of & #8220 ost-rift& #8221 thermal re-equilibration of upper mantle after late Palaeozoic rifting, this rift phase occurred with a stretching factor of c 1.4. That this thermal subsidence was modulated by differential uplift and erosion of the Brian& #231 onnais in the early Jurassic implies significant mantle thinning, reducing net density of the Brian& #231 onnais lithosphere. The subsidence of more than 3000m during Bathonian-Callovian stages are too rapid to be explained by thermal re-equilibration: it suggests substantial crustal thinning. Our results demonstrate that a uniform stretching model is not able to explain the Jurassic isostatic movement of the Brian& #231 onnais domain. It is consistent with two-stage, depth-variable stretching of the Brian& #231 onnais lithosphere during the Jurassic. Our study represents a starting point for more sophisticated and developed numerical models, to explain rapid vertical movements in hyper-extended continental margins.& &
Publisher: American Geophysical Union (AGU)
Date: 09-2016
DOI: 10.1002/2016JB013460
Publisher: Elsevier BV
Date: 02-2003
Publisher: Springer Science and Business Media LLC
Date: 02-2021
Abstract: A measurement of CP -violating observables is performed using the decays B ± → DK ± and B ± → Dπ ± , where the D meson is reconstructed in one of the self-conjugate three-body final states $$ {K}_{\\mathrm{S}}^0 $$ K S 0 π + π − and $$ {K}_{\\mathrm{S}}^0 $$ K S 0 K + K − (commonly denoted $$ {K}_{\\mathrm{S}}^0 $$ K 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 litude. The observables are inter- preted in terms of the CKM angle γ . Using a data s le corresponding to an integrated luminosity of 9 fb − 1 collected in proton-proton collisions at centre-of mass energies of 7, 8, and 13 TeV with the LHCb experiment, γ is measured to be $$ \\left({68.7}_{-5.1}^{+5.2}\\right){}^{\\circ} $$ 68.7 − 5.1 + 5.2 ° . The hadronic parameters $$ {r}_B^{D K},{r}_B^{D\\pi},{\\delta}_B^{D K},\\kern0.5em \\mathrm{and}\\kern0.5em {\\delta}_B^{D\\pi} $$ r B DK , r B Dπ , δ B DK , and δ B Dπ , which are the ratios and strong-phase differences of the suppressed and favoured B ± decays, are also reported.
Publisher: Elsevier BV
Date: 2000
Publisher: Elsevier BV
Date: 12-1999
Publisher: Elsevier BV
Date: 08-2020
Publisher: Copernicus GmbH
Date: 27-03-2022
DOI: 10.5194/EGUSPHERE-EGU22-3025
Abstract: & & The Black Sea is a deep marine basin formed by lithosphere extension and active rifting in a Tethyan back-arc tectonic setting in the Cretaceous, which by general consensus is taken to represent the main process forming the present-day basin (although significant post-rift deformation has occurred). Rifting took place within continental lithosphere that had earlier been accreted to and, by this time, formed part of the Eurasian lithospheric plate. The present-day crust is thin though the lithosphere appears to be of typical thickness. A much-debated issue about the Black Sea is whether Cretaceous rifting was intense enough to have led to oceanic or & #8220 sub-oceanic& #8221 crust formation prior to the deposition of the overlying thick Cretaceous and younger sedimentary succession. This is the focus of the present multidisciplinary study, which integrates detailed subsurface mapping in the Ukrainian sector of the northern Black Sea with regional geophysical characterisations of the lithosphere and the record of pre-Cretaceous Tethyan belt geology of the area. These allow new quantitative basin modelling that strongly suggests that Cretaceous rifting was insufficient to reveal exhumed continental mantle or to promote ocean crust formation. Legacy extensional tectonic events affecting the area in pre-Cretaceous times are inferred to be important for explaining the observed present-day crustal and lithosphere architecture of the Black Sea area. The results are likely relevant to the formation and eventual consumption of back-arc basins in the Tethyan orogenic belt generally.& &
Publisher: Elsevier BV
Date: 11-1999
Publisher: Geological Society of London
Date: 2018
DOI: 10.1144/SP472.9
Publisher: Geological Society of London
Date: 23-08-2019
DOI: 10.1144/JGS2019-018
Publisher: Springer Science and Business Media LLC
Date: 10-2021
Abstract: This article presents differential measurements of the asymmetry between $$ {\\varLambda}_b^0 $$ Λ b 0 and $$ {\\overline{\\varLambda}}_b^0 $$ Λ ¯ b 0 baryon production rates in proton-proton collisions at centre-of-mass energies of $$ \\sqrt{s} $$ s = 7 and 8 TeV collected with the LHCb experiment, corresponding to an integrated luminosity of 3 fb − 1 . The $$ {\\varLambda}_b^0 $$ Λ b 0 baryons are reconstructed through the inclusive semileptonic decay $$ {\\varLambda}_b^0 $$ Λ b 0 → $$ {\\varLambda}_c^{+} $$ Λ c + μ − $$ \\overline{\\nu} $$ ν ¯ μ X . The production asymmetry is measured both in intervals of rapidity in the range 2 . 15 y 4 . 10 and transverse momentum in 2 p T 27 GeV/ c . The results are found to be incompatible with symmetric production with a significance of 5.8 standard deviations for both $$ \\sqrt{s} $$ s = 7 and 8 TeV data, assuming no CP violation in the decay. There is evidence for a trend as a function of rapidity with a significance of 4 standard deviations. Comparisons to predictions from hadronisation models in P ythia and heavy-quark recombination are provided. This result constitutes the first observation of a particle-antiparticle asymmetry in b -hadron production at LHC energies.
Publisher: Elsevier BV
Date: 12-1995
Publisher: Elsevier BV
Date: 07-2020
Publisher: American Physical Society (APS)
Date: 05-03-2021
Publisher: American Physical Society (APS)
Date: 20-09-2021
Publisher: Elsevier BV
Date: 08-2021
Publisher: American Physical Society (APS)
Date: 27-12-2021
Publisher: Elsevier BV
Date: 07-2021
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for Randell Stephenson.