Displaying publications 61 - 80 of 209 in total

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  1. Fulltext Identification of α-glucosidase inhibitors from Clinacanthus nutans leaf extract using liquid chromatography-mass spectrometry-based metabolomics and protein-ligand interaction with molecular docking
    Murugesu S, Ibrahim Z, Ahmed QU, Uzir BF, Nik Yusoff NI, Perumal V, et al.
    J Pharm Anal, 2019 Apr;9(2):91-99.
    PMID: 31011465 DOI: 10.1016/j.jpha.2018.11.001
    The present study used in vitro and in silico techniques, as well as the metabolomics approach to characterise α-glucosidase inhibitors from different fractions of Clinacanthus nutans. C. nutans is a medicinal plant belonging to the Acanthaceae family, and is traditionally used to treat diabetes in Malaysia. n-Hexane, n-hexane: ethyl acetate (1:1, v/v), ethyl acetate, ethyl acetate: methanol (1:1, v/v), and methanol fractions were obtained via partitioning of the 80% methanolic crude extract. The in vitro α-glucosidase inhibitory activity was analyzed using all the fractions collected, followed by profiling of the metabolites using liquid chromatography combined with mass spectrometry. The partial least square (PLS) statistical model was developed using the SIMCA P+14.0 software and the following four inhibitors were obtained: (1) 4,6,8-Megastigmatrien-3-one; (2) N-Isobutyl-2-nonen-6,8-diynamide; (3) 1',2'-bis(acetyloxy)-3',4'-didehydro-2'-hydro-β, ψ-carotene; and (4) 22-acetate-3-hydroxy-21-(6-methyl-2,4-octadienoate)-olean-12-en-28-oic acid. The in silico study performed via molecular docking with the crystal structure of yeast isomaltase (PDB code: 3A4A) involved a hydrogen bond and some hydrophobic interactions between the inhibitors and protein. The residues that interacted include ASN259, HID295, LYS156, ARG335, and GLY209 with a hydrogen bond, while TRP15, TYR158, VAL232, HIE280, ALA292, PRO312, LEU313, VAL313, PHE314, ARG315, TYR316, VAL319, and TRP343 with other forms of bonding.
  2. Impact of GSK199 and GSK106 binding on protein arginine deiminase IV stability and flexibility: A computational approach
    Zainal Fithri HH, Ibrahim Z, Ali EZ
    Comput Biol Chem, 2023 Dec;107:107962.
    PMID: 37847978 DOI: 10.1016/j.compbiolchem.2023.107962
    Protein arginine deiminase IV (PAD4) is a potential target for diseases including rheumatoid arthritis and cancers. Currently, GSK199 is a potent, selective yet reversible PAD4 inhibitor. Its derivative, GSK106, on the other hand, was reported as an inactive compound when tested against PAD4 assay. Although they had similar skeleton, their impact towards PAD4 structural and flexibility is unknown. In order to fill the research gap, the impact of GSK199 and GSK106 binding towards PAD4 stability and flexibility is investigated via a combination of computational methods. Molecular docking indicates that GSK199 and GSK106 are capable to bind at PAD4 pocket by using its back door with -10.6 kcal/mol and -9.6 kcal/mol, respectively. The simulations of both complexes were stable throughout 100 ns. The structure of PAD4 exhibited a tighter packing in the presence of GSK106 compared to GSK199. The RMSF analysis demonstrates significant changes between the PAD4-GSK199 and PAD4-GSK106 simulations in the regions containing residues 136, 160, 220, 438, and 606. The Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA) analysis shows a marked difference in binding free energies, with -11.339 kcal/mol for the PAD4-GSK199 complex and 1.063 kcal/mol for the PAD4-GSK106 complex. The hydrogen bond analysis revealed that the GSK199 and GSK106 binding to PAD4 are assisted by six hydrogen bonds and three hydrogen bonds, respectively. The visualisation of the MD simulations revealed that GSK199 remained in the PAD4 pocket, whereas GSK106 shifted away from the catalytic site. Meanwhile, molecular dockings of benzoyl arginine amide (BAEE) substrate have shown that BAEE is able to bind to PAD4 catalytic site when GSK106 was present but not when GSK199 occupied the site. Overall, combination of computational approaches successfully described the behaviour of binding pocket of PAD4 structure in the presence of the active and inactive compounds.
  3. Fulltext Improving Vector Evaluated Particle Swarm Optimisation by incorporating nondominated solutions
    Lim KS, Ibrahim Z, Buyamin S, Ahmad A, Naim F, Ghazali KH, et al.
    ScientificWorldJournal, 2013;2013:510763.
    PMID: 23737718 DOI: 10.1155/2013/510763
    The Vector Evaluated Particle Swarm Optimisation algorithm is widely used to solve multiobjective optimisation problems. This algorithm optimises one objective using a swarm of particles where their movements are guided by the best solution found by another swarm. However, the best solution of a swarm is only updated when a newly generated solution has better fitness than the best solution at the objective function optimised by that swarm, yielding poor solutions for the multiobjective optimisation problems. Thus, an improved Vector Evaluated Particle Swarm Optimisation algorithm is introduced by incorporating the nondominated solutions as the guidance for a swarm rather than using the best solution from another swarm. In this paper, the performance of improved Vector Evaluated Particle Swarm Optimisation algorithm is investigated using performance measures such as the number of nondominated solutions found, the generational distance, the spread, and the hypervolume. The results suggest that the improved Vector Evaluated Particle Swarm Optimisation algorithm has impressive performance compared with the conventional Vector Evaluated Particle Swarm Optimisation algorithm.
  4. Inclusive Search for a Highly Boosted Higgs Boson Decaying to a Bottom Quark-Antiquark Pair
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 Feb 16;120(7):071802.
    PMID: 29542941 DOI: 10.1103/PhysRevLett.120.071802
    An inclusive search for the standard model Higgs boson (H) produced with large transverse momentum (p_{T}) and decaying to a bottom quark-antiquark pair (bb[over ¯]) is performed using a data set of pp collisions at sqrt[s]=13  TeV collected with the CMS experiment at the LHC. The data sample corresponds to an integrated luminosity of 35.9  fb^{-1}. A highly Lorentz-boosted Higgs boson decaying to bb[over ¯] is reconstructed as a single, large radius jet, and it is identified using jet substructure and dedicated b tagging techniques. The method is validated with Z→bb[over ¯] decays. The Z→bb[over ¯] process is observed for the first time in the single-jet topology with a local significance of 5.1 standard deviations (5.8 expected). For a Higgs boson mass of 125 GeV, an excess of events above the expected background is observed (expected) with a local significance of 1.5 (0.7) standard deviations. The measured cross section times branching fraction for production via gluon fusion of H→bb[over ¯] with reconstructed p_{T}>450  GeV and in the pseudorapidity range -2.5
  5. Fulltext Intraosseous synovial sarcoma of the proximal femur: Case report
    Zulkarnaen M, Pan K, Shanmugam P, Ibrahim Z, Chan W
    Malays Orthop J, 2012 Mar;6(1):49-52.
    PMID: 25279044 MyJurnal DOI: 10.5704/MOJ.1203.003
    ABSTRACT: Synovial sarcoma is primarily a soft tissue malignancy that most often affects adolescents and young adults. It very rarely presents as a primary bone tumour and has only been reported in nine other cases to date. We report a case of primary synovial sarcoma arising from the proximal femur in a 57-year-old man.

    KEY WORDS: Synovial sarcoma, primary bone tumour.

  6. Isolation of Potential Bacteria as Inoculum for Biofloc Formation in Pacific Whiteleg Shrimp, Litopenaeus vannamei Culture Ponds
    Kasan NA, Ghazali NA, Ikhwanuddin M, Ibrahim Z
    Pak J Biol Sci, 2017;20(6):306-313.
    PMID: 29023055 DOI: 10.3923/pjbs.2017.306.313
    BACKGROUND AND OBJECTIVE: A new green technology to reduce environmental damages while optimizing production of Pacific Whiteleg shrimp, Litopenaeus vannamei was developed known as "Biofloc technology". Microbial communities in biofloc aggregates are responsible in eliminating water exchange and producing microbial proteins that can be used as supplemented feed for L. vannamei. This study aimed to isolate and identify potential bioflocculant-producing bacteria to be used as inoculum for rapid formation of biofloc.

    MATERIALS AND METHODS: For the purpose of this study, bacterial communities during 0, 30 and 70 days of culture (DOC) of L. vannamei grow-out ponds were isolated and identified through phenotypic and 16S rDNA sequences analysis. Phylogenetic relationships between isolated bacteria were then evaluated through phylogenetic tree analysis. One-way analysis of variance (ANOVA) was used to compare the differences of microbial communities at each DOC.

    RESULTS: Out of 125 bacterial isolates, nine species of bacteria from biofloc were identified successfully. Those bacteria species were identified as Halomonas venusta, H. aquamarina, Vibrio parahaemolyticus, Bacillus infantis, B. cereus, B. safensis, Providencia vermicola, Nitratireductor aquimarinus and Pseudoalteromonas sp., respectively. Through phylogenetic analysis, these isolates belong to Proteobacteria and Firmicutes families under the genera of Halomonas sp., Vibrio sp., Bacillus sp., Providencia sp., Nitratireductor sp. and Pseudoalteromonas sp.

    CONCLUSION: In this study, bioflocculant-producing bacteria were successfully identified which are perfect candidates in forming biofloc to reduce water pollution towards a sustainable aquaculture industry. Presence of Halomonas sp. and Bacillus sp. in all stages of biofloc formation reinforces the need for new development regarding the ability of these species to be used as inoculum in forming biofloc rapidly.

  7. Jet Shapes of Isolated Photon-Tagged Jets in Pb-Pb and pp Collisions at sqrt[s_{NN}]=5.02  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2019 Apr 19;122(15):152001.
    PMID: 31050516 DOI: 10.1103/PhysRevLett.122.152001
    The modification of jet shapes in Pb-Pb collisions, relative to those in pp collisions, is studied for jets associated with an isolated photon. The data were collected with the CMS detector at the LHC at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Jet shapes are constructed from charged particles with track transverse momenta (p_{T}) above 1  GeV/c in annuli around the axes of jets with p_{T}^{jet}>30  GeV/c associated with an isolated photon with p_{T}^{γ}>60  GeV/c. The jet shape distributions are consistent between peripheral Pb-Pb and pp collisions, but are modified for more central Pb-Pb collisions. In these central Pb-Pb events, a larger fraction of the jet momentum is observed at larger distances from the jet axis compared to pp, reflecting the interaction between the partonic medium created in heavy ion collisions and the traversing partons.
  8. Kinetic and equilibrium studies of the removal of ammonium ions from aqueous solution by rice husk ash-synthesized zeolite Y and powdered and granulated forms of mordenite
    Yusof AM, Keat LK, Ibrahim Z, Majid ZA, Nizam NA
    J Hazard Mater, 2010 Feb 15;174(1-3):380-5.
    PMID: 19879040 DOI: 10.1016/j.jhazmat.2009.09.063
    The removal of ammonium from aqueous solutions using zeolite NaY prepared from a local agricultural waste, rice husk ash waste was investigated and a naturally occurring zeolite mordenite in powdered and granulated forms was used as comparison. Zeolite NaY and mordenite were well characterized by powder X-ray diffraction (XRD), energy dispersive X-ray (EDX) analysis and the total cation exchange capacity (CEC). CEC of the zeolites were measured as 3.15, 1.46 and 1.34 meq g(-1) for zeolite Y, powdered mordenite and granular mordenite, respectively. Adsorption kinetics and equilibrium data for the removal of NH(4)(+) ions were examined by fitting the experimental data to various models. Kinetic studies showed that the adsorption followed a pseudo-second-order reaction. The equilibrium pattern fits well with the Langmuir isotherm compared to the other isotherms. The monolayer adsorption capacity for zeolite Y (42.37 mg/g) was found to be higher than that powdered mordenite (15.13 mg/g) and granular mordenite (14.56 mg/g). Thus, it can be concluded that the low cost and economical rice husk ash-synthesized zeolite NaY could be a better sorbent for ammonium removal due to its rapid adsorption rate and higher adsorption capacity compared to natural mordenite.
  9. Luminescence characteristics of Li₂CO₃-K₂CO₃-H₃BO₃ glasses co-doped with TiO₂/MgO
    Alajerami YS, Hashim S, Ghoshal SK, Ramli AT, Saleh MA, Ibrahim Z, et al.
    Appl Radiat Isot, 2013 Dec;82:12-9.
    PMID: 23948307 DOI: 10.1016/j.apradiso.2013.07.005
    Understanding the influence of co-dopants in the luminescence enhancement of carbonate glasses is the key issue in dosimetry. A series of borate glasses modified by lithium and potassium carbonate were synthesized by the melt-quenching method. The glass mixture activated with various concentrations of TiO2 and MgO was subjected to various doses of gamma-rays ((60)Co). The amorphous nature of the samples was confirmed by x-ray diffraction (XRD) spectra. The simple glowing curve of the glass doped with TiO2 features a peak at 230°C, whose intensity is maximal at 0.5 mol% of the dopant. The intensity of the glowing curve increases with the concentration of MgO added as a co-dopant up to 0.25 mol%, where it is two times higher than for the material without MgO thermoluminescence properties, including dose response, reproducibility, and fading were studied. The effective atomic number of the material was also determined. Kinetic parameters, such as kinetics order, activation energy, and frequency factor are estimated. The photoluminescence spectra of the titanium-doped glass consist of a prominent peaks at 480 nm when laser excitation at 650 nm is used. A three-fold photoluminescence enhancement and a blue shift of the peak were observed when 0.1% MgO was introduced. In addition, various physical parameters, such as ion concentration, polaron radius and internuclear distances were calculated. The mechanism for the thermoluminescence and photoluminescence enhancements are discussed.
  10. Fulltext Machinability and surface quality of hybrid composite CFRP/Al2024
    Mohamed, S.B., Mohamad, W.N.F.W., Yew, B.S., Ibrahim, Z., Musanih, M.R., Zitoune, R., et al.
    Malaysian Journal of Applied Sciences, 2018;2(2):37-44.
    MyJurnal
    The use of hybrid composite has increased due to their special mechanical and physical properties.
    However, machining of composite materials is extremely difficult due to non-homogeneous,
    anisotropic and highly abrasive characteristics. The performance of machined surface quality of
    CFRP/Al2024 was described using two level full factorial methodology. Trimming test was performed
    under dry conditions using 6mm diameter of burr tools end mills. The factors investigated were spindle
    speed(N), feed rate(fr) and depth of cut(dc), furthermore Ra CFRP and Ra Al2024 were the response
    variables. This work aims to minimize the machined surface quality of CFRP/Al2024 between 1µm to
    2µm. The finding of this empirical study has shown that, the best estimated value of fr should be 500
    mm/min to 530 mm/min, N is between and 2313.870 rpm to 2336.042 rpm. For both response spindle
    speed is the most significant effect followed by Feed rate and Depth of Cut.
  11. Fulltext Measurement of Long-Range Near-Side Two-Particle Angular Correlations in pp Collisions at sqrt[s]=13  TeV
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2016 Apr 29;116(17):172302.
    PMID: 27176516 DOI: 10.1103/PhysRevLett.116.172302
    Results on two-particle angular correlations for charged particles produced in pp collisions at a center-of-mass energy of 13 TeV are presented. The data were taken with the CMS detector at the LHC and correspond to an integrated luminosity of about 270  nb^{-1}. The correlations are studied over a broad range of pseudorapidity (|η|<2.4) and over the full azimuth (ϕ) as a function of charged particle multiplicity and transverse momentum (p_{T}). In high-multiplicity events, a long-range (|Δη|>2.0), near-side (Δϕ≈0) structure emerges in the two-particle Δη-Δϕ correlation functions. The magnitude of the correlation exhibits a pronounced maximum in the range 1.0
  12. Measurement of Prompt D^{0} Meson Azimuthal Anisotropy in Pb-Pb Collisions at sqrt[s_{NN}]=5.02  TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Phys Rev Lett, 2018 May 18;120(20):202301.
    PMID: 29864330 DOI: 10.1103/PhysRevLett.120.202301
    The prompt D^{0} meson azimuthal anisotropy coefficients, v_{2} and v_{3}, are measured at midrapidity (|y|<1.0) in Pb-Pb collisions at a center-of-mass energy sqrt[s_{NN}]=5.02  TeV per nucleon pair with data collected by the CMS experiment. The measurement is performed in the transverse momentum (p_{T}) range of 1 to 40  GeV/c, for central and midcentral collisions. The v_{2} coefficient is found to be positive throughout the p_{T} range studied. The first measurement of the prompt D^{0} meson v_{3} coefficient is performed, and values up to 0.07 are observed for p_{T} around 4  GeV/c. Compared to measurements of charged particles, a similar p_{T} dependence, but smaller magnitude for p_{T}<6  GeV/c, is found for prompt D^{0} meson v_{2} and v_{3} coefficients. The results are consistent with the presence of collective motion of charm quarks at low p_{T} and a path length dependence of charm quark energy loss at high p_{T}, thereby providing new constraints on the theoretical description of the interactions between charm quarks and the quark-gluon plasma.
  13. Fulltext Measurement of [Formula: see text] production with additional jet activity, including [Formula: see text] quark jets, in the dilepton decay channel using pp collisions at [Formula: see text]
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016;76(7):379.
    PMID: 28280447 DOI: 10.1140/epjc/s10052-016-4105-x
    Jet multiplicity distributions in top quark pair ([Formula: see text]) events are measured in pp collisions at a centre-of-mass energy of 8 TeV with the CMS detector at the LHC using a data set corresponding to an integrated luminosity of 19.7[Formula: see text]. The measurement is performed in the dilepton decay channels ([Formula: see text], [Formula: see text], and [Formula: see text]). The absolute and normalized differential cross sections for [Formula: see text] production are measured as a function of the jet multiplicity in the event for different jet transverse momentum thresholds and the kinematic properties of the leading additional jets. The differential [Formula: see text] and [Formula: see text] cross sections are presented for the first time as a function of the kinematic properties of the leading additional [Formula: see text] jets. Furthermore, the fraction of events without additional jets above a threshold is measured as a function of the transverse momenta of the leading additional jets and the scalar sum of the transverse momenta of all additional jets. The data are compared and found to be consistent with predictions from several perturbative quantum chromodynamics event generators and a next-to-leading order calculation.
  14. Fulltext Measurement of associated Z + charm production in proton-proton collisions at s = 8 TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2018;78(4):287.
    PMID: 31007580 DOI: 10.1140/epjc/s10052-018-5752-x
    A study of the associated production of a Z boson and a charm quark jet ( Z + c ), and a comparison to production with a b quark jet ( Z + b ), in p p collisions at a centre-of-mass energy of 8 TeV are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 fb - 1 , collected with the CMS detector at the CERN LHC. The Z boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of c or b flavoured hadrons and hadronic decays of charm hadrons. The measurements are performed in the kinematic region with two leptons with p T ℓ > 20 GeV , | η ℓ | < 2.1 , 71 < m ℓ ℓ < 111 GeV , and heavy flavour jets with p T jet > 25 GeV and | η jet | < 2.5 . The Z + c production cross section is measured to be σ ( p p → Z + c + X ) B ( Z → ℓ + ℓ - ) = 8.8 ± 0.5 (stat) ± 0.6 (syst) pb . The ratio of the Z + c and Z + b production cross sections is measured to be σ ( p p → Z + c + X ) / σ ( p p → Z + b + X ) = 2.0 ± 0.2 (stat) ± 0.2 (syst) . The Z + c production cross section and the cross section ratio are also measured as a function of the transverse momentum of the Z boson and of the heavy flavour jet. The measurements are compared with theoretical predictions.
  15. Fulltext Measurement of associated production of a W boson and a charm quark in proton-proton collisions at s = 13 Te
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2019;79(3):269.
    PMID: 30971865 DOI: 10.1140/epjc/s10052-019-6752-1
    Measurements are presented of associated production of a W boson and a charm quark ( W + c ) in proton-proton collisions at a center-of-mass energy of 13 Te . The data correspond to an integrated luminosity of 35.7 fb - 1 collected by the CMS experiment at the CERN LHC. The W bosons are identified by their decay into a muon and a neutrino. The charm quarks are tagged via the full reconstruction of D ∗ ( 2010 ) ± mesons that decay via D ∗ ( 2010 ) ± → D 0 + π ± → K ∓ + π ± + π ± . A cross section is measured in the fiducial region defined by the muon transverse momentum p T μ > 26 Ge , muon pseudorapidity | η μ | < 2.4 , and charm quark transverse momentum p T c > 5 Ge . The inclusive cross section for this kinematic range is σ ( W + c ) = 1026 ± 31 (stat) + 76 - 72 (syst) pb . The cross section is also measured differentially as a function of the pseudorapidity of the muon from the W boson decay. These measurements are compared with theoretical predictions and are used to probe the strange quark content of the proton.
  16. Fulltext Measurement of b hadron lifetimes in pp collisions at s = 8 TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2018;78(6):457.
    PMID: 30956548 DOI: 10.1140/epjc/s10052-018-5929-3
    Measurements are presented of the lifetimes of the B 0 , B s 0 , Λ b 0 , and B c + hadrons using the decay channels B 0 → J / ψ K ∗ ( 892 ) 0 , B 0 → J / ψ K S 0 , B s 0 → J / ψ π + π - , B s 0 → J / ψ ϕ ( 1020 ) , Λ b 0 → J / ψ Λ 0 , and B c + → J / ψ π + . The data sample, corresponding to an integrated luminosity of 19.7 fb -1 , was collected by the CMS detector at the LHC in proton-proton collisions at s = 8 TeV . The B 0 lifetime is measured to be 453.0 ± 1.6 (stat) ± 1.8 (syst) μ m in J / ψ K ∗ ( 892 ) 0 and 457.8 ± 2.7 (stat) ± 2.8 (syst) μ m in J / ψ K S 0 , which results in a combined measurement of c τ B 0 = 454.1 ± 1.4 (stat) ± 1.7 (syst) μ m . The effective lifetime of the B s 0 meson is measured in two decay modes, with contributions from different amounts of the heavy and light eigenstates. This results in two different measured lifetimes: c τ B s 0 → J / ψ π + π - = 502.7 ± 10.2 (stat) ± 3.4 (syst) μ m and c τ B s 0 → J / ψ ϕ ( 1020 ) = 443.9 ± 2.0 (stat) ± 1.5 (syst) μ m . The Λ b 0 lifetime is found to be 442.9 ± 8.2 (stat) ± 2.8 (syst) μ m . The precision from each of these channels is as good as or better than previous measurements. The B c + lifetime, measured with respect to the B + to reduce the systematic uncertainty, is 162.3 ± 7.8 (stat) ± 4.2 (syst) ± 0.1 ( τ B + ) μ m . All results are in agreement with current world-average values.
  17. Fulltext Measurement of charged particle spectra in minimum-bias events from proton-proton collisions at s = 13 TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2018;78(9):697.
    PMID: 30839770 DOI: 10.1140/epjc/s10052-018-6144-y
    Pseudorapidity, transverse momentum, and multiplicity distributions are measured in the pseudorapidity range | η | < 2.4 for charged particles with transverse momenta satisfying p T > 0.5 GeV in proton-proton collisions at a center-of-mass energy of s = 13 TeV . Measurements are presented in three different event categories. The most inclusive of the categories corresponds to an inelastic p p data set, while the other two categories are exclusive subsets of the inelastic sample that are either enhanced or depleted in single diffractive dissociation events. The measurements are compared to predictions from Monte Carlo event generators used to describe high-energy hadronic interactions in collider and cosmic-ray physics.
  18. Fulltext Measurement of differential cross sections and charge ratios for t-channel single top quark production in proton-proton collisions at s = 13 Te
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Brandstetter J, et al.
    Eur Phys J C Part Fields, 2020;80(5):370.
    PMID: 32633732 DOI: 10.1140/epjc/s10052-020-7858-1
    A measurement is presented of differential cross sections for t-channel single top quark and antiquark production in proton-proton collisions at a centre-of-mass energy of 13 Te by the CMS experiment at the LHC. From a data set corresponding to an integrated luminosity of 35.9 fb - 1 , events containing one muon or electron and two or three jets are analysed. The cross section is measured as a function of the top quark transverse momentum ( p T ), rapidity, and polarisation angle, the charged lepton p T and rapidity, and the p T of the W  boson from the top quark decay. In addition, the charge ratio is measured differentially as a function of the top quark, charged lepton, and W  boson kinematic observables. The results are found to be in agreement with standard model predictions using various next-to-leading-order event generators and sets of parton distribution functions. Additionally, the spin asymmetry, sensitive to the top quark polarisation, is determined from the differential distribution of the polarisation angle at parton level to be 0.440 ± 0.070 , in agreement with the standard model prediction.
  19. Measurement of differential cross sections for Higgs boson production in the diphoton decay channel in pp collisions at [Formula: see text]
    Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2016 01 11;76:13.
    PMID: 26855607
    A measurement is presented of differential cross sections for Higgs boson (H) production in pp collisions at [Formula: see text][Formula: see text]. The analysis exploits the [Formula: see text] decay in data corresponding to an integrated luminosity of 19.7[Formula: see text] collected by the CMS experiment at the LHC. The cross section is measured as a function of the kinematic properties of the diphoton system and of the associated jets. Results corrected for detector effects are compared with predictions at next-to-leading order and next-to-next-to-leading order in perturbative quantum chromodynamics, as well as with predictions beyond the standard model. For isolated photons with pseudorapidities [Formula: see text], and with the photon of largest and next-to-largest transverse momentum ([Formula: see text]) divided by the diphoton mass [Formula: see text] satisfying the respective conditions of [Formula: see text] and [Formula: see text], the total fiducial cross section is [Formula: see text][Formula: see text].
  20. Fulltext Measurement of differential cross sections for Z boson production in association with jets in proton-proton collisions at s = 13 TeV
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2018;78(11):965.
    PMID: 30881214 DOI: 10.1140/epjc/s10052-018-6373-0
    The production of a Z boson, decaying to two charged leptons, in association with jets in proton-proton collisions at a centre-of-mass energy of 13 TeV is measured. Data recorded with the CMS detector at the LHC are used that correspond to an integrated luminosity of 2.19 fb -1 . The cross section is measured as a function of the jet multiplicity and its dependence on the transverse momentum of the Z boson, the jet kinematic variables (transverse momentum and rapidity), the scalar sum of the jet momenta, which quantifies the hadronic activity, and the balance in transverse momentum between the reconstructed jet recoil and the Z boson. The measurements are compared with predictions from four different calculations. The first two merge matrix elements with different parton multiplicities in the final state and parton showering, one of which includes one-loop corrections. The third is a fixed-order calculation with next-to-next-to-leading order accuracy for the process with a Z boson and one parton in the final state. The fourth combines the fully differential next-to-next-to-leading order calculation of the process with no parton in the final state with next-to-next-to-leading logarithm resummation and parton showering.
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