Measurement of the triple-differential cross section for photon plus jets production in proton-proton collisions at √s = 7 TeV

Peer reviewe

Measurement of the inelastic proton-proton cross section at root s=13 TeV

A measurement of the inelastic proton-proton cross section with the CMS detector at a center-of-mass energy of root s = 13 TeV is presented. The analysis is based on events with energy deposits in the forward calorimeters, which cover pseudorapidities of -6.6 4.1 GeV and/or M-Y > 13 GeV, where M-x and M-Y are the masses of the diffractive dissociation systems at negative and positive pseudorapidities, respectively. The results are compared with those from other experiments as well as to predictions from high-energy hadron-hadron interaction models.Peer reviewe

Measurement of the W-boson helicity in top-quark decays from t(t)over-bar production in lepton plus jets events in pp collisions at √s=7 TeV

This is the pre-print version of the final published article that can be accessed at the link below.The W-boson helicity fractions in top-quark decays are measured with tt events in the lepton+jets final state, using proton-proton collisions at a centre-of-mass energy of 7 TeV, collected in 2011 with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 5.0 fb-1. The measured fractions of longitudinal, left-, and right-handed helicity are F0 = 0.682 0.030 (stat.) 0.033 (syst.), FL = 0.310 0.022 (stat.) 0.022 (syst.), and FR = 0.008 0.012 (stat.) 0.014 (syst.), consistent with the standard model predictions. The measured fractions are used to probe the existence of anomalous Wtb couplings. Exclusion limits on the real components of the anomalous couplings gL, gR are also derived

Search for ZZ resonances in the 2l2v final state in proton-proton collisions at 13 TeV

A search for heavy resonances decaying to a pair of Z bosons is performed using data collected with the CMS detector at the LHC. Events are selected by requiring two oppositely charged leptons (electrons or muons), consistent with the decay of a Z boson, and large missing transverse momentum, which is interpreted as arising from the decay of a second Z boson to two neutrinos. The analysis uses data from proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). The hypothesis of a spin-2 bulk graviton (X) decaying to a pair of Z bosons is examined for 600 ZZ ranging from 100 to 4 fb. For bulk graviton models characterized by a curvature scale parameter (k) over tilde = 0.5 in the extra dimension, the region nix <800 GeV is excluded, providing the most stringent limit reported to date. Variations of the model considering the possibility of a wide resonance produced exclusively via gluon-gluon fusion or q annihilation are also examined.Peer reviewe

Measurement of the triple-differential cross section for photon plus jets production in proton-proton collisions at=7 TeV

A measurement of the triple-differential cross section, d3&#963;/(dp&#947;Td&#951;&#947;d&#951;jet) , in photon + jets final states using a data sample from proton-proton collisions at s&#8730; = 7 TeV is presented. This sample corresponds to an integrated luminosity of 2.14 fb &#8722;1 collected by the CMS detector at the LHC. Photons and jets are reconstructed within a pseudorapidity range of | &#951; | 30 GeV, respectively. The measurements are compared to theoretical predictions from the sherpa leading-order QCD Monte Carlo event generator and the next-to-leading-order perturbative QCD calculation from jetphox. The predictions are found to be consistent with the data over most of the examined kinematic region

Разработка дизайна оболочки велотренажера для людей с ограниченными физическими возможностями

Объектом исследования является велотренажер для людей с ограниченными физическими возможностями. Цель работы – проектирование оболочки велотренажера для людей с ограниченными физическими возможностями. В процессе проектирования проводилась разработка вариантов дизайнерских решений оболочки корпуса. В результате проектирования была разработана велотренажера для людей с ограниченными физическими возможностями.The object of the study is an exercise bike for people with disabilities. The aim of the work is to design the shell of an exercise bike for people with disabilities. In the design process, the development of variants of the design solutions of the hull shell was carried out. As a result of the design, an exercise bike was developed for people with disabilities

Measurement of the inelastic proton-proton cross section at s=13 \sqrt{s}=13 TeV

A measurement of the inelastic proton-proton cross section with the CMS detector at a center-of-mass energy of s√=13 TeV is presented. The analysis is based on events with energy deposits in the forward calorimeters, which cover pseudorapidities of −6.6 4.1 GeV and/or MY > 13 GeV, where MX and MY are the masses of the diffractive dissociation systems at negative and positive pseudorapidities, respectively. The results are compared with those from other experiments as well as to predictions from high-energy hadron-hadron interaction models

Search for low mass vector resonances decaying into quark-antiquark pairs in proton-proton collisions at √s =13 TeV

A search for narrow vector resonances decaying into quark-antiquark pairs is presented. The analysis is based on data collected in proton-proton collisions at s √ =13 s=13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 35.9 fb−1. The hypothetical resonance is produced with sufficiently high transverse momentum that its decay products are merged into a single jet with two-prong substructure. A signal would be identified as a peak over a smoothly falling background in the distribution of the invariant mass of the jet, using novel jet substructure techniques. No evidence for such a resonance is observed within the mass range of 50-300 GeV. Upper limits at 95% confidence level are set on the production cross section, and presented in a mass-coupling parameter space. The limits further constrain simplified models of dark matter production involving a mediator interacting between quarks and dark matter particles through a vector or axial-vector current. In the framework of these models, the results are the most sensitive to date, extending for the first time the search region to masses below 100 GeV

Measurement of the production cross sections for a Z boson and one or more b jets in pp collisions at s s√ = 7 TeV

The production of a Z boson, decaying into two leptons and produced in association with one or more b jets, is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV. The data were recorded in 2011 with the CMS detector and correspond to an integrated luminosity of 5 fb &#8722;1 . The Z( &#8467;&#8467; ) + b-jets cross sections (where &#8467;&#8467; = &#956;&#956; or ee) are measured separately for a Z boson produced with exactly one b jet and with at least two b jets. In addition, a cross section ratio is extracted for a Z boson produced with at least one b jet, relative to a Z boson produced with at least one jet. The measured cross sections are compared to various theoretical predictions, and the data favour the predictions in the five-flavour scheme, where b quarks are assumed massless. The kinematic properties of the reconstructed particles are compared with the predictions from the M ad G raph event generator using the pythia parton shower simulation