Measurements of differential production cross sections for a Z boson in association with jets in pp collisions at root s=8 TeV

Peer reviewe

Search for the associated production of the Higgs boson with a top-quark pair

A search for the standard model Higgs boson produced in association with a top-quark pair t t ¯ H (tt¯H) is presented, using data samples corresponding to integrated luminosities of up to 5.1 fb −1 and 19.7 fb −1 collected in pp collisions at center-of-mass energies of 7 TeV and 8 TeV respectively. The search is based on the following signatures of the Higgs boson decay: H → hadrons, H → photons, and H → leptons. The results are characterized by an observed t t ¯ H tt¯H signal strength relative to the standard model cross section, μ = σ/σ SM ,under the assumption that the Higgs boson decays as expected in the standard model. The best fit value is μ = 2.8 ± 1.0 for a Higgs boson mass of 125.6 GeV

Measurement of prompt Jψ\psi pair production in pp collisions at \sqrt s = 7 Tev

Production of prompt J/ ψ meson pairs in proton-proton collisions at s s√ = 7 TeV is measured with the CMS experiment at the LHC in a data sample corresponding to an integrated luminosity of about 4.7 fb −1 . The two J/ ψ mesons are fully reconstructed via their decays into μ + μ − pairs. This observation provides for the first time access to the high-transverse-momentum region of J/ ψ pair production where model predictions are not yet established. The total and differential cross sections are measured in a phase space defined by the individual J/ ψ transverse momentum ( p T J/ ψ ) and rapidity (| y J/ ψ |): | y J/ ψ | 6.5 GeV/ c ; 1.2 4.5 GeV/ c . The total cross section, assuming unpolarized prompt J/ ψ pair production is 1.49 ± 0.07 (stat) ±0.13 (syst) nb. Different assumptions about the J/ ψ polarization imply modifications to the cross section ranging from −31% to +27%

Charged-particle nuclear modification factors in PbPb and pPb collisions at √=sNN=5.02 TeV

The spectra of charged particles produced within the pseudorapidity window |η| < 1 at √ sNN = 5.02 TeV are measured using 404 µb −1 of PbPb and 27.4 pb−1 of pp data collected by the CMS detector at the LHC in 2015. The spectra are presented over the transverse momentum ranges spanning 0.5 < pT < 400 GeV in pp and 0.7 < pT < 400 GeV in PbPb collisions. The corresponding nuclear modification factor, RAA, is measured in bins of collision centrality. The RAA in the 5% most central collisions shows a maximal suppression by a factor of 7–8 in the pT region of 6–9 GeV. This dip is followed by an increase, which continues up to the highest pT measured, and approaches unity in the vicinity of pT = 200 GeV. The RAA is compared to theoretical predictions and earlier experimental results at lower collision energies. The newly measured pp spectrum is combined with the pPb spectrum previously published by the CMS collaboration to construct the pPb nuclear modification factor, RpA, up to 120 GeV. For pT > 20 GeV, RpA exhibits weak momentum dependence and shows a moderate enhancement above unity

Method of implementing graded index media by symmetry-reduced helical photonic structures

We propose a new approach for the realization of a graded index (GRIN) medium using a symmetry reduced unit element in photonic crystals. An index gradient on the order of ?n = 0.16 is achieved without modifying the filling fraction or cell size dimensions. Various beam manipulation techniques can be implemented with such a GRIN medium. We show that designed GRIN structure may effectively focus an incident beam over wide bandwidth. The arrangement of the photonic crystal (PC) elements within unit cells exhibits structural order which is helical along the transverse to propagation direction. The designed GRIN PC structurally resembles the molecular orientation of cholesteric liquid crystals. © 2015 Optical Society of America

Reduced symmetry and analogy to chirality in periodic dielectric media

Much attention has been paid to photonic applications based on periodic media. Meanwhile, quasi-periodic and disordered mediahave extended the research domain and provided additional novelties for manipulating and controlling light propagation. This review article attempts to highlight the benefits of symmetry reduction in highly symmetric periodic photonic media, and applies the concept of chirality to all-dielectric materials arranged in special orders. Two-dimensional periodic structures known as photonic crystals (PCs) are highly symmetric in terms of structural patterns, due to the lattice types and shape of the elements occupying the PC unit-cell. We propose the idea of intentionally introducing reduced-symmetry, to search for anomalous optical characteristics so that these types of PCs can be used in the design of novel optical devices. Breaking either translational or rotational symmetries of PCs provides enhanced and additional optical characteristics such as creation of a complete photonic bandgap, wavelength demultiplexing, super-collimation, tilted self-collimation, and beam deflecting/routing properties. Utilizing these characteristics allows the design of several types of photonic devices such as polarization-independent waveguides, wavelength demultiplexers, beam deflectors, and routers. Moreover, reducing the symmetry in the PC unit-cell scale produces a novel feature in all-dielectric PCs that is known as chirality. On the basis of above considerations, it is expected that low-symmetric PCs can be considered as a potential structure in photonic device applications, due to the rich inherent optical properties, providing broadband operation, and being free of absorption losses. © 2014, European Optical Society (EOS). All rights reserved

The effect of streptokinase therapy in STEMI and conventional therapy in NSTEMI patients on TIMI risk index, B-type natriuretic peptide and high-sensitive C-reactive protein [Akut stemi'de streptokinaz tedavisi ve NSTEMI'de konvansiyonel tedavinin ti·mi· risk indeksi, B-tip natriüretik peptit ve yüksek-duyarlikli C-reaktif protein üzerindeki etkisi]

PubMedID: 21821500Objective: In this study, it was aimed to investigate the effect of streptokinase therapy in ST elevation myocardial infarction (STEMI) and conventional therapy in non-ST elevation myocardial infarction (NSTEMI) patients on the thrombolysis in myocardial infarction (TIMI) risk index (TRI), B-type natriuretic peptide (BNP), and high-sensitive C-reactive protein (hs-CRP) levels. Methods: Eighty-six STEMI (male/female ratio: 65/21, mean age 57.52±9.87 years) and eighty NSTEMI patients (male/female ratio: 50/30, mean age 57.6±1.7 years) were included in this prospective observational study. Hs-CRP and BNP were measured and TIMI risk index was calculated in all patients. Coronary angiography was performed in all patients for principally determining TIMI flow rate. Chi-square test, paired t-test or Wilcoxon signed rank test, ANOVA and Spearman correlation analysis were used for statistical analysis where appropriate. Results: STEMI patients had higher systolic blood pressure, heart rate, BNP and hs-CRP values than NSTEMI patients at admission (p=0.04, p=0.01, p=0.001 and p=0.01, respectively). Thrombolytic therapy in STEMI patients resulted in statistically significant higher levels of BNP, hs-CRP and TRI values compared to baseline levels (p=0.001, p=0.001 and p=0.042, respectively). For NSTEMI patients conventional therapy yielded statistically significant decrease in systolic blood pressure levels and increase in TRI (p=0.001 and p=0.047, respectively). We found significantly lower BNP, hs-CRP in patients with higher TIMI flow rate (p=0.001 and p=0.001 respectively). Conclusion: Thrombolytic therapy with streptokinase failed to decrease BNP, hs-CRP and TRI values in STEMI patients. Conventional therapy in NSTEMI patients also resulted in higher TRI values than baseline values. We reached TIMI 3 flow in only 10.5% of the study patients, which may be responsible for our findings. © 2011 by AVES Yayi{dotless}nci{dotless}li{dotless}k Ltd