Results are presented from searches for the standard model Higgs boson in proton-proton collisions at root s = 7 and 8 TeV in the Compact Muon Solenoid experiment at the LHC, using data samples corresponding to integrated luminosities of up to 5.1 fb(-1) at 7 TeV and 5.3 fb(-1) at 8 TeV. The search is performed in five decay modes: gamma gamma, ZZ, W+W-, tau(+)tau(-), and b (b) over bar. An excess of events is observed above the expected background, with a local significance of 5.0 standard deviations, at a mass near 125 GeV, signalling the production of a new particle. The expected significance for a standard model Higgs boson of that mass is 5.8 standard deviations. The excess is most significant in the two decay modes with the best mass resolution, gamma gamma and ZZ; a fit to these signals gives a mass of 125.3 +/- 0.4(stat.) +/- 0.5(syst.) GeV. The decay to two photons indicates that the new particle is a boson with spin different from one.BMWF ; FWF ; FNRS ; FWO ; CNPq ; CAPES ; FAPERJ ; FAPESP ; MEYS ; CERN ; CAS ; MoST ; NSFC ; COLCIENCIAS ; MSES ; RPF ; MoER ; SF0690030s09 ; ERDF ; Academy of Finland ; MEC ; HIP ; CEA ; CNRS/IN2P3 ; BMBF ; DFG ; HGF ; GSRT ; OTKA ; NKTH ; DAE ; DST ; IPM ; SFI ; INFN ; NRF ; WCU ; LAS ; CINVESTAV ; CONACYT ; SEP ; UASLP-FAI ; MSI ; PAEC ; MSHE ; NSC ; FCT ; JINR ; MON ; RosAtom ; RAS ; RFBR ; MSTD ; SEIDI ; CPAN ; Swiss Funding Agencies ; NSC ; ThEPCenter ; IPST ; NSTDA ; TUBITAK ; TAEK ; NASU ; STFC ; University of California Institute for Mexico and the United States ; the Marie-Curie programme and the European Research Council and EPLANET ; DOE and NSF ; the Leventis Foundation ; the A. P. Sloan Foundation ; the Alexander von Humboldt Foundation ; the Belgian Federal Science Policy Office ; the Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture ; the Agentschap voor Innovatie door Wetenschap en Technologie ; the Ministry of Education, Youth and Sports of Czech Republic ; the Agence Nationale de la Recherche ANR-12-JS05-002-01 ; the Council of Science and Industrial Research, India; the Compagnia di San Paolo ; the HOMING PLUS programme of Foundation for Polish Science, cofinanced by EU ; Regional Development Fund

New sets of parameters (“tunes”) for the underlying-event (UE) modelling of the pythia8, pythia6 and herwig++Monte Carlo event generators are constructed using different parton distribution...

Results on two-particle angular correlations for charged particles emitted in proton-proton collisions at center-of-mass energies of 0.9, 2.36, and 7 TeV are presented, using data collected with the CMS detector over a broad range of pseudorapidity (η) and azimuthal angle (ϕ). Short-range correlations in Δη, which are studied in minimum bias events, are characterized using a simple “independent cluster” parametrization in order to quantify their strength (cluster size) and their extent in η (cluster decay width). Long-range azimuthal correlations are studied differentially as a function of charged particle multiplicity and particle transverse momentum using a 980 nb⁻¹ data set at 7 TeV. In high multiplicity events, a pronounced structure emerges in the two-dimensional correlation function for particle pairs with intermediate p _T of 1–3 GeV/c, 2.0 < |Δη| < 4.8 and Δϕ ≈ 0. This is the first observation of such a long-range, near-side feature in two-particle correlation functions in pp or \( p\overline p \) collisions.

Jet production in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV was studied with the Compact Muon Solenoid (CMS) detector at the LHC, using a data sample corresponding to an integrated luminosity of $6.7\mu$b${}^{-1}$. Jets are reconstructed using the energy deposited in the CMS calorimeters and studied as a function of collision centrality. With increasing collision centrality, a striking imbalance in dijet transverse momentum is observed, consistent with jet quenching. The observed effect extends from the lower cutoff used in this study (jet $p_{\mathrm{T}}=120$ GeV/c) up to the statistical limit of the available data sample (jet $p_{\mathrm{T}}\approx 210$ GeV/c). Correlations of charged particle tracks with jets indicate that the momentum imbalance is accompanied by a softening of the fragmentation pattern of the second most energetic, away-side jet. The dijet momentum balance is recovered when integrating low transverse momentum particles distributed over a wide angular range relative to the direction of the away-side jet.

The transverse momentum spectra of charged particles have been measured in pp and PbPb collisions at [equation] by the CMS experiment at the LHC. In the transverse momentum range pT=5–10 GeV/ c, the...