Search for jet extinction in the inclusive jet-pT spectrum from proton-proton collisions at s=8 TeV

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and DOI.The first search at the LHC for the extinction of QCD jet production is presented, using data collected with the CMS detector corresponding to an integrated luminosity of 10.7  fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV. The extinction model studied in this analysis is motivated by the search for signatures of strong gravity at the TeV scale (terascale gravity) and assumes the existence of string couplings in the strong-coupling limit. In this limit, the string model predicts the suppression of all high-transverse-momentum standard model processes, including jet production, beyond a certain energy scale. To test this prediction, the measured transverse-momentum spectrum is compared to the theoretical prediction of the standard model. No significant deficit of events is found at high transverse momentum. A 95% confidence level lower limit of 3.3 TeV is set on the extinction mass scale

Search for three-jet resonances in pp collisions at √s=7 TeV

This is a Pre-Print version of the Article - Copyright @ 2011 APSA model-independent search for three-jet hadronic resonance production in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity of 35 inverse picobarns. Events with high jet multiplicity and a large scalar sum of jet transverse momenta are analyzed. The number of expected standard model background events is found to be in good agreement with the observed events. Limits are set on a model describing the production of R-parity-violating supersymmetric gluino pairs, and gluino masses in the range of 200 to 280 GeV/c^2 are excluded at a 95% confidence level for the first time.This work is supported by the FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia); Academy of Finland, ME, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF andWCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE (Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA)

Searches for electroweak neutralino and chargino production in channels with Higgs, Z, and W bosons in pp collisions at 8 TeV

Searches for supersymmetry (SUSY) are presented based on the electroweak pair production of neutralinos and charginos, leading to decay channels with Higgs, Z, and W bosons and undetected lightest SUSY particles (LSPs). The data sample corresponds to an integrated luminosity of about 19.5 fb(-1) of proton-proton collisions at a center-of-mass energy of 8 TeV collected in 2012 with the CMS detector at the LHC. The main emphasis is neutralino pair production in which each neutralino decays either to a Higgs boson (h) and an LSP or to a Z boson and an LSP, leading to hh, hZ, and ZZ states with missing transverse energy (E-T(miss)). A second aspect is chargino-neutralino pair production, leading to hW states with E-T(miss). The decays of a Higgs boson to a bottom-quark pair, to a photon pair, and to final states with leptons are considered in conjunction with hadronic and leptonic decay modes of the Z and W bosons. No evidence is found for supersymmetric particles, and 95% confidence level upper limits are evaluated for the respective pair production cross sections and for neutralino and chargino mass values

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

The total cross-section of (5pi)-nucleon collision

Coherent 5\u3c0 production on nine nuclear targets has been studied at 40 GeV incident energy at the Serpukhov accelerator (CERN-Serpukhov experiment No. 5). The collision cross section of the 5\u3c0 system on the nucleon has been determined in the frame of the K\uf6lbig-Margolis-Glauber model; its value, <10 mb, is definitely lower than the (3\u3c0)-nucleon cross section at the same energy

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

CMS Physics Technical Design Report: Addendum on High Density QCD with Heavy Ions

This report presents the capabilities of the CMS experiment to explore the rich heavy-ion physics programme offered by the CERN Large Hadron Collider (LHC). The collisions of lead nuclei at energies $\sqrt{s_{NN}}= 5.5\,{\rm TeV}$ , will probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research is to study the fundamental theory of the strong interaction \u2014 Quantum Chromodynamics (QCD) \u2014 in extreme conditions of temperature, density and parton momentum fraction (low- x ). This report covers in detail the potential of CMS to carry out a series of representative Pb-Pb measurements. These include "bulk" observables, (charged hadron multiplicity, low p T inclusive hadron identified spectra and elliptic flow) which provide information on the collective properties of the system, as well as perturbative probes such as quarkonia, heavy-quarks, jets and high p T hadrons which yield "tomographic" information of the hottest and densest phases of the reaction