Publications by authors named "McNab A"

Article Synopsis
  • The study investigates CP symmetry violation in the decay of D^{+} particles into K^{-}K^{+}π^{+} using data from proton-proton collisions at a high energy of 13 TeV.
  • A unique model-independent method was employed to analyze the phase-space distributions of D^{+} and D^{-} particles, correcting for any instrumental biases using D_{s}^{+} decays.
  • The findings indicate no significant evidence of CP violation, with a p value of 8.1%, and measure specific CP asymmetry observables, marking this study as the most sensitive search of its kind in multibody decays.
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Article Synopsis
  • This study focused on identifying risk factors and management outcomes for patients with orbital cellulitis stemming from dacryocystitis, analyzing a group of 18 patients.
  • The majority of patients (56% female, mean age 62) experienced reduced visual acuity, but most showed improvement after treatment, with acute intervention helping in resolving acute cellulitis.
  • Key findings suggested that recurrent dacryocystitis and the presence of dacryoliths are significant risk factors, while immunosuppression worsens prognosis; successful long-term resolution typically requires dacryocystorhinostomy.
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Purpose: To characterise patterns of disease recurrence in idiopathic orbital myositis (IOM).

Methods: Multi-centre retrospective longitudinal study of IOM patients. Serial imaging was also analysed.

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Background: Idiopathic apical orbital inflammation (AOI) is used to describe inflammation involving the posterior third of the orbit where no specific cause can be identified. It is a rare entity in which the presentation can vary widely. We aim to describe a case series of patients with idiopathic AOI and their clinicoradiological features and visual outcomes.

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Article Synopsis
  • A study was conducted on B^{+} decays to explore resonant structures using data from the LHCb experiment at various energy levels, totaling an integrated luminosity of 9 fb^{-1}.
  • The researchers performed a simultaneous amplitude fit on two decay channels, determining the C parities of resonances in the D^{*±}D^{∓} mass spectra.
  • Four new charmonium or charmoniumlike states were discovered, including η_{c}(3945) and h_{c}(4000), and the presence of T_{c[over ¯]s[over ¯]0}^{*}(2870)^{0} and T_{c[over ¯]s
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A measurement of time-dependent CP violation in D^{0}→π^{+}π^{-}π^{0} decays using a pp collision data sample collected by the LHCb experiment in 2012 and from 2015 to 2018, corresponding to an integrated luminosity of 7.7  fb^{-1}, is presented. The initial flavor of each D^{0} candidate is determined from the charge of the pion produced in the D^{*}(2010)^{+}→D^{0}π^{+} decay.

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Purpose: The purpose of this study was to provide Australian data on the clinical and radiological features and outcomes in patients with orbital plasmacytomas.

Methods: Multicentre retrospective review of orbital plasmacytoma and orbital involvement in multiple myeloma (MM) from 2005 to 2022 in Australia.

Results: Twenty-one participants were identified.

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Background: Endovascular embolization of carotid-cavernous sinus dural arteriovenous fistulas (CCFs) is most commonly performed via a transfemoral-transvenous approach. Surgical cut-down of the superior ophthalmic vein is an alternative, well-described route. When these prove inaccessible, a transorbital approach can be used to reach the fistula.

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The LHCb Collaboration measures production of the exotic hadron χ_{c1}(3872) in proton-nucleus collisions for the first time. Comparison with the charmonium state ψ(2S) suggests that the exotic χ_{c1}(3872) experiences different dynamics in the nuclear medium than conventional hadrons, and comparison with data from proton-proton collisions indicates that the presence of the nucleus may modify χ_{c1}(3872) production rates. This is the first measurement of the nuclear modification factor of an exotic hadron.

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Background: Posterior movement of ocular tissue secondary to orbital cavernous venous malformation shrinkage from fractionated stereotactic radiotherapy can allow healthy structures to move into the radiation field during treatment. This may carry an increased risk of radiation-induced retinopathy.

Methods: We present a case of a young female whose radiotherapy treatment for an orbital cavernous venous malformation resulted in a 3 mm reduction in proptosis and subsequent retinopathy.

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Article Synopsis
  • - Calcification in pleomorphic adenomas of the lacrimal gland is rare and more common in lacrimal gland cancers, while bony formation (ossification) is even less frequent.
  • - Occurrences of extensive sclerosis and ossification may indicate a higher risk of cancer transformation, but these changes can sometimes be mistaken for malignant conditions, confusing diagnosis.
  • - Two case reports are discussed where patients with presumed pleomorphic adenomas showed histopathological signs of ossification and necrosis, yet no evidence of malignancy or invasive disease was found.
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An amplitude analysis of the B^{0}→K^{*0}μ^{+}μ^{-} decay is presented using a dataset corresponding to an integrated luminosity of 4.7  fb^{-1} of pp collision data collected with the LHCb experiment. For the first time, the coefficients associated to short-distance physics effects, sensitive to processes beyond the standard model, are extracted directly from the data through a q^{2}-unbinned amplitude analysis, where q^{2} is the μ^{+}μ^{-} invariant mass squared.

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The fraction of χ_{c1} and χ_{c2} decays in the prompt J/ψ yield, F_{χ_{c}→J/ψ}=σ_{χ_{c}→J/ψ}/σ_{J/ψ}, is measured by the LHCb detector in pPb collisions at sqrt[s_{NN}]=8.16  TeV. The study covers the forward (1.

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The first observation of the singly Cabibbo-suppressed Ω_{c}^{0}→Ω^{-}K^{+} and Ω_{c}^{0}→Ξ^{-}π^{+} decays is reported, using proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4  fb^{-1}, collected with the LHCb detector between 2016 and 2018. The branching fraction ratios are measured to be B(Ω_{c}^{0}→Ω^{-}K^{+})/B(Ω_{c}^{0}→Ω^{-}π^{+})=[6.

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The production rate of Λ_{b}^{0} baryons relative to B^{0} mesons in pp collisions at a center-of-mass energy sqrt[s]=13  TeV is measured by the LHCb experiment. The ratio of Λ_{b}^{0} to B^{0} production cross sections shows a significant dependence on both the transverse momentum and the measured charged-particle multiplicity. At low multiplicity, the ratio measured at LHCb is consistent with the value measured in e^{+}e^{-} collisions, and increases by a factor of ∼2 with increasing multiplicity.

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Purpose: To characterize the qualitative and quantitative features of idiopathic orbital myositis (IOM) on MRI.

Methods: This was a multicenter retrospective study of patients with active IOM with MRI. Patients with incomplete clinical records, poor-quality or interval scans without active myositis, and specific orbital myositis (i.

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The decay-time-dependent CP asymmetry in B_{s}^{0}→J/ψ(→μ^{+}μ^{-})K^{+}K^{-} decays is measured using proton-proton collision data, corresponding to an integrated luminosity of 6  fb^{-1}, collected with the LHCb detector at a center-of-mass energy of 13 TeV. Using a sample of approximately 349 000 B_{s}^{0} signal decays with an invariant K^{+}K^{-} mass in the vicinity of the ϕ(1020) resonance, the CP-violating phase ϕ_{s} is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the B_{s}^{0}-B[over ¯]_{s}^{0} system, ΔΓ_{s}, and the difference of the average B_{s}^{0} and B^{0} meson decay widths, Γ_{s}-Γ_{d}. The values obtained are ϕ_{s}=-0.

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A measurement of time-dependent CP violation in the decays of B^{0} and B[over ¯]^{0} mesons to the final states J/ψ(→μ^{+}μ^{-})K_{S}^{0}, ψ(2S)(→μ^{+}μ^{-})K_{S}^{0} and J/ψ(→e^{+}e^{-})K_{S}^{0} with K_{S}^{0}→π^{+}π^{-} is presented. The data correspond to an integrated luminosity of 6  fb^{-1} collected at a center-of-mass energy of sqrt[s]=13  TeV with the LHCb detector. The CP-violation parameters are measured to be S_{ψK_{S}^{0}}=0.

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A flavor-tagged time-dependent angular analysis of the decay B_{s}^{0}→ϕϕ is performed using pp collision data collected by the LHCb experiment at the center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6  fb^{-1}. The CP-violating phase and direct CP-violation parameter are measured to be ϕ_{s}^{ss[over ¯]s}=-0.042±0.

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The first observation and study of two new baryonic structures in the final state Ξ_{b}^{0}π^{+}π^{-} and the confirmation of the Ξ_{b}(6100)^{-} state in the Ξ_{b}^{-}π^{+}π^{-} decay mode are reported using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. In addition, the properties of the known Ξ_{b}^{*0}, Ξ_{b}^{'-} and Ξ_{b}^{*-} resonances are measured with improved precision. The new decay mode of the Ξ_{b}^{0} baryon to the Ξ_{c}^{+} π^{-} π^{+} π^{-} final state is observed and exploited for the first time in these measurements.

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The branching fraction of the rare decay Λ_{b}^{0}→Λ(1520)μ^{+}μ^{-} is measured for the first time, in the squared dimuon mass intervals q^{2}, excluding the J/ψ and ψ(2S) regions. The data sample analyzed was collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9  fb^{-1}. The result in the highest q^{2} interval, q^{2}>15.

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An amplitude analysis of B^{0}→J/ψϕK_{S}^{0} decays is performed using proton-proton collision data, corresponding to an integrated luminosity of 9  fb^{-1}, collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. Evidence with a significance of 4.0 standard deviations of a structure in the J/ψK_{S}^{0} system, named T_{ψs1}^{θ}(4000)^{0}, is seen, with its mass and width measured to be 3991_{-10}^{+12} _{-17}^{+9}  MeV/c^{2} and 105_{-25}^{+29} _{-23}^{+17}  MeV, respectively, where the first uncertainty is statistical and the second systematic.

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Two new excited states, Ω_{c}(3185)^{0} and Ω_{c}(3327)^{0}, are observed in the Ξ_{c}^{+}K^{-} invariant-mass spectrum using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. Five previously observed excited Ω_{c}^{0} states are confirmed, namely Ω_{c}(3000)^{0}, Ω_{c}(3050)^{0}, Ω_{c}(3065)^{0}, Ω_{c}(3090)^{0}, and Ω_{c}(3119)^{0}. The masses and widths of these seven states are measured with the highest precision to date.

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The ratios of branching fractions R(D^{*})≡B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}μ^{-}ν[over ¯]_{μ}) and R(D^{0})≡B(B^{-}→D^{0}τ^{-}ν[over ¯]_{τ})/B(B^{-}→D^{0}μ^{-}ν[over ¯]_{μ}) are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0  fb^{-1} of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ^{-}→μ^{-}ν_{τ}ν[over ¯]_{μ}.

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Article Synopsis
  • The LHCb experiment measures prompt D^{0} meson production in proton-lead collisions at a center-of-mass energy of 8.16 TeV, focusing on both forward and backward rapidity regions.
  • Results reveal significant suppression of D^{0} meson production in the forward rapidity region compared to proton-proton collisions, offering valuable insights into nuclear parton distribution models.
  • In the backward rapidity region, a noteworthy suppression is also observed, particularly in high transverse momentum ranges, challenging existing parton distribution function predictions in a nuclear context.
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