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This study was carried out in preparation for the conservation of the oil painted dome of Archangel Gabriel church located at Haret El Saqqayeen in Abdeen (Cairo). Stratigraphic, chemical and environmental studies were conducted to examine the painting technique and to assess the conservation state of the dome. The dome was imaged using Multi-spectral imaging and samples were collected from representative areas. Cross-sections were investigated by the means of scanning electron microscopy coupled with dispersive energy of X-ray spectrometer (SEM-EDS) and stereo microscopy. Fourier transformed infrared spectroscopy (FTIR) and gas chromatography-mass spectroscopy (GC/MS) was employed for the identification of the paint medium. X-ray diffraction (XRD) and the colorimetric measurements were conducted for characterization the differences of hues between the original and non-original pigments. As a part of the study, the environment within the dome was measured with data loggers and gas sampling. The results showed that the painted dome dates back to two different periods. The older paintings were applied before 1907 and were covered by ground layers to be repainted in 1907. Non-professional over-painting and the uncontrolled indoor climate have a significant role in the deterioration phenomena of the dome.

A model-dependent amplitude analysis of the decay B0→D(K0Sπ+π−)K∗0 is performed using proton-proton collision data corresponding to an integrated luminosity of 3.0fb−1, recorded at s√=7 and 8TeV by the LHCb experiment. The CP violation observables x± and y±, sensitive to the CKM angle γ, are measured to bex−=−0.15±0.14±0.03±0.01,y−=0.25±0.15±0.06±0.01,x+=0.05±0.24±0.04±0.01,y+=−0.65+0.24−0.23±0.08±0.01,where the first uncertainties are statistical, the second systematic and the third arise from the uncertainty on the D→K0Sπ+π− amplitude model. These are the most precise measurements of these observables. They correspond to γ=(80+21−22)∘ and rB0=0.39±0.13, where rB0 is the magnitude of the ratio of the suppressed and favoured B0→DK+π− decay amplitudes, in a Kπ mass region of ±50MeV around the K∗(892)0 mass and for an absolute value of the cosine of the K∗0 decay angle larger than 0.4.

Associated production of bottomonia and open charm hadrons inppcollisions at√s̅=7and8 TeV is observed using data corresponding to an integrated luminosity of 3 fb⁻¹accumulated with the LHCb detector. The observation of five combinations,Υ(1S)D⁰ ,Υ(2S)D⁰ ,Υ(1S)D⁺ ,Υ(2S)D⁺andΥ(1S)D⁺_(s) , is reported. Production cross-sections are measured forΥ(1S)D⁰andΥ(1S)D⁺pairs in the forward region. The measured cross-sections and the differential distributions indicate the dominance of double parton scattering as the main production mechanism. This allows a precise measurement of the effective cross-section for double parton scattering.

The first model-independent measurement of the charm mixing parameters in the decayD⁰ → K_(S) π⁺ π⁻is reported, using a sample ofppcollision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 1.0 fb ⁻¹at a centre-of-mass energy of 7 TeV. The measured values are eqnarray* x &=& (+0.86 0.53 0.17) 10⁻2, y &=& (+0.03 0.46 0.13) 10⁻2, eqnarray* where the first uncertainties are statistical and include small contributions due to the external input for the strong phase measured by the CLEO collaboration, and the second uncertainties are systematic. The results are consistent with the current world averages.

Production cross-sections of prompt charm mesons are measured with the first data from$pp$collisions at the LHC at a centre-of-mass energy of$13\\,\\mathrm{TeV}$ . The data sample corresponds to an integrated luminosity of$4.98 \\pm 0.19\\,\\mathrm{pb}^{-1}$collected by the LHCb experiment. The production cross-sections of$D^{0}$ ,$D^{+}$ ,$D_{s}^{+}$ , and$D^{*+}$mesons are measured in bins of charm meson transverse momentum,$p_{\\mathrm{T}}$ , and rapidity,$y$ , and cover the range$0 < p_{\\mathrm{T}} < 15\\,\\mathrm{GeV}/c$and$2.0 < y < 4.5$ . The ratios of the integrated cross-sections between charm mesons agree with previously measured fragmentation fractions. The inclusive$c\\overline{c}$cross-section within the range of$0 < p_{\\mathrm{T}} < 8\\,\\mathrm{GeV}/c$is found to be \\[ (pp ccX) = 2940 3 180 160\\, \\] where the uncertainties are due to statistical, systematic and fragmentation fraction uncertainties, respectively.

TheB_(s)⁰ → J/ψ φ φdecay is observed inppcollision data corresponding to an integrated luminosity of 3 fb ⁻¹recorded by the LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV. This is the first observation of this decay channel, with a statistical significance of 15 standard deviations. The mass of theB_(s)⁰meson is measured to be5367.08 ± 0.38 ± 0.15MeV/c ² . The branching fraction ratio𝓑(B_(s)⁰ → J/ψ φ φ)/𝓑(B_(s)⁰ → J/ψ φ)is measured to be0.0115 ± 0.0012 ^(+0.0005)_(-0.0009) . In both cases, the first uncertainty is statistical and the second is systematic. No evidence for non-resonantB_(s)⁰ → J/ψ φ K⁺ K⁻orB_(s)⁰ → J/ψ K⁺ K⁻ K⁺ K⁻decays is found.

An angular analysis of the$B^{0}\\rightarrow K^{*0}(\\rightarrow K^{+}\\pi^{-})\\mu^{+}\\mu^{-}$decay is presented. The dataset corresponds to an integrated luminosity of$3.0\\,{\\mbox{fb}^{-1}}$of$pp$collision data collected at the LHCb experiment. The complete angular information from the decay is used to determine$C\\!P$ -averaged observables and$C\\!P$asymmetries, taking account of possible contamination from decays with the$K^{+}\\pi^{-}$system in an S-wave configuration. The angular observables and their correlations are reported in bins of$q^2$ , the invariant mass squared of the dimuon system. The observables are determined both from an unbinned maximum likelihood fit and by using the principal moments of the angular distribution. In addition, by fitting for$q^2$ -dependent decay amplitudes in the region$1.1

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