Constraints on the Higgs boson width from off-shell production and decay to Z-boson pairs

Constraints are presented on the total width of the recently discovered Higgs boson, GH, using its relative on-shell and off-shell production and decay rates to a pair of Z bosons, where one Z boson decays to an electron or muon pair, and the other to an electron, muon, or neutrino pair. The analysis is based on the data collected by the CMS experiment at the LHC in 2011 and 2012, corresponding to integrated luminosities of 5.1fb-1 at a center-of-mass energy vs=7 TeV and 19.7fb-1at vs=8 TeV. A simultaneous maximum likelihood fit to the measured kinematic distributions near the resonance peak and above the Z-boson pair production threshold leads to an upper limit on the Higgs boson width of GH<22 MeV at a 95% confidence level, which is 5.4 times the expected value in the standard model at the measured mass of mH=125.6 GeV

Do Chinese SOEs and Private Companies Differ in Their Foreign Location Strategies?

We empirically analyze the host-country determinants of Chinese outbound foreign direct investments (ODI) in the period from 2003 to 2008, using disaggregated data by country and sector and distinguishing between State-owned enterprises (SOEs) and privately owned firms. Our results show that the pattern of Chinese ODI differs according to corporate ownership. Private firms are attracted by large markets and host-country strategic assets and are averse to economic and political risks when choosing investment locations abroad. Differently, state-owned enterprises follow the strategic needs of their home country and invest more in natural resource sectors, being largely indifferent to the political and economic conditions in the host countries

Measurement of forward-backward asymmetry A FB and of the weak mixing angle in processes of dilepton production in proton-proton collisions at 1as = 7 TeV in the CMS experiment at the LHC

The results obtained by measuring the forward \u2013 backward asymmetry ( A FB ) of Drell \u2013 Yan lepton pairs in proton \u2013 proton collisions at 1as =7 TeV at the LHC are presented. This asymmetry is measured as a function of the dilepton mass and rapidity in the dielectron and dimuon channels. The values of A FB were found for invariant masses of dileptons in the range of 40 M ll 600 GeV. The results for the e ff ective weak mixing angle that were deduced from data on dimuon production in Drell \u2013 Yan processes are also presented. The respective data sample was collected by using the Compact Muon Solenoid (CMS) detector over the period spanning the years 2010 and 2011. The measured asymmetry and the e ff ective weak mixing are consistent with the respective Standard Model predictions

Search for supersymmetry in pp collisions at sqrt(s) = 8 TeV in events with a single lepton, large jet multiplicity, and multiple b jets

Submitted to Phys. Lett. B ; see paper for full list of authorsResults are reported from a search for supersymmetry in pp collisions at a center-of-mass energy of 8 TeV, based on events with a single isolated lepton (e or mu) and multiple jets, at least two of which are identified as b jets. The data sample corresponds to an integrated luminosity of 19.3 inverse femtobarns recorded by the CMS experiment at the LHC in 2012. The search is motivated by supersymmetric models that involve strong-production processes and cascade decays of new particles. The resulting final states contain multiple jets as well as missing transverse momentum from weakly interacting particles. The event yields, observed across several kinematic regions, are consistent with the expectations from standard model processes predicted from control samples in the data. The results are interpreted in the context of simplified supersymmetric scenarios with pair production of gluinos, where each gluino decays to a top quark-antiquark pair and the lightest neutralino. For the case of decays via virtual top squarks, gluinos with a mass smaller than 1.26 TeV are excluded for low neutralino masses

Searches for signals from microscopic black holes in processes of proton collisions at 1as = 7 TeV in the CMS experiment at the LHC

If the fundamental scale of mul tidimensional gravity is about one or several TeV units, microscopic black holes or objects referred to as string balls may be produced at the LHC. The most recent results obtained by the CMS Collaboration at the LHC from searches for such signals at the c.m. proton- interaction energy of 7 TeV and for an integrated luminosity of 4.7 fb 12 1 . Lower limits on the masses of objects of strongly acting gravity were set in the parameter region accessible to tests at the present time. Prospects for further research in this field are discusse

Energy calibration and resolution of the CMS electromagnetic calorimeter in pp collisions at s\sqrt{s} = 7 TeV

The energy calibration and resolution of the electromagnetic calorimeter (ECAL) of the CMS detector have been determined using proton-proton collision data from LHC operation in 2010 and 2011 at a centre-of-mass energy of sqrt(s)=7 TeV with integrated luminosities of about 5 inverse femtobarns. Crucial aspects of detector operation, such as the environmental stability, alignment, and synchronization, are presented. The in-situ calibration procedures are discussed in detail and include the maintenance of the calibration in the challenging radiation environment inside the CMS detector. The energy resolution for electrons from Z-boson decays is better than 2% in the central region of the ECAL barrel (for pseudorapidity abs(eta)<0.8) and is 2-5% elsewhere. The derived energy resolution for photons from 125 GeV Higgs boson decays varies across the barrel from 1.1% to 2.6% and from 2.2% to 5% in the entraps. The calibration of the absolute energy is determined from Z to e+e- decays to a precision of 0.4% in the barrel and 0.8% in the endcaps