118691822
Search for microscopic black holes in pp collisions at $ \sqrt{s}=8 $ TeV
A bstractA search for microscopic black holes and string balls is presented, based on a data sample of pp collisions at $ \sqrt{s}=8 $ TeV recorded by the CMS experiment at the Large Hadron Collider and corresponding to an integrated luminosity of 12 fb−1. No excess of events with energetic multiparticle final states, typical of black hole production or of similar new physics processes, is observed. Given the agreement of the observations with the expected standard model background, which is dominated by QCD multijet production, 95% confidence level limits are set on the production of semiclassical or quantum black holes, or of string balls, corresponding to the exclusions of masses below 4.3 to 6.2 TeV, depending on model assumptions. In addition, model-independent limits are set on new physics processes resulting in energetic multiparticle final states.

841502
Observation of the diphoton decay of the Higgs boson and measurement of its properties
Observation of the diphoton decay mode of the recently discovered Higgs boson and measurement of some of its properties are reported. The analysis uses the entire dataset collected by the CMS experiment in proton-proton collisions during the 2011 and 2012 LHC running periods. The data samples correspond to integrated luminosities of 5.1$$\,\text {fb}^\text {-1}$$fb-1at $$\sqrt{s}=7\,\text {TeV}\,$$s=7TeV and 19.7$$\,\text {fb}^\text {-1}$$fb-1at 8$$\,\text {TeV}$$TeV . A clear signal is observed in the diphoton channel at a mass close to 125$$\,\text {GeV}$$GeV with a local significance of $$5.7\,\sigma $$5.7σ, where a significance of $$5.2\,\sigma $$5.2σ is expected for the standard model Higgs boson. The mass is measured to be $$124.70\pm 0.34\,\text {GeV} \,=124.70\pm 0.31\,\text {(stat)}\,\pm 0.15\,\text {(syst)}\,\,\text {GeV} \,$$124.70±0.34GeV=124.70±0.31(stat)±0.15(syst)GeV , and the best-fit signal strength relative to the standard model prediction is $$1.14^\mathrm{+0.26}_{-0.23}=1.14\pm 0.21\,\text {(stat)}\,$$1.14-0.23+0.26=1.14±0.21(stat)$$^\mathrm{+0.09}_{-0.05}\,\text {(syst)}\,$$-0.05+0.09(syst)$$^\mathrm{+0.13}_{-0.09}\,\text {(theo)}\,$$-0.09+0.13(theo). Additional measurements include the signal strength modifiers associated with different production mechanisms, and hypothesis tests between spin-0 and spin-2 models.
37672579
Search for heavy neutrinos and $$\mathrm {W}$$W bosons with right-handed couplings in proton–proton collisions at $$\sqrt{s} = 8\,\text {TeV} $$s=8TeV
A search for heavy, right-handed neutrinos, $$\mathrm {N}_{\ell }$$Nℓ ($$\ell = \mathrm {e}, \mu $$ℓ=e,μ), and right-handed $$\mathrm {W}_{\mathrm {R}}$$WR bosons, which arise in the left-right symmetric extensions of the standard model, has been performed by the CMS experiment. The search was based on a sample of two lepton plus two jet events collected in proton–proton collisions at a center-of-mass energy of 8$$\,\text {TeV}$$TeV corresponding to an integrated luminosity of 19.7 $$\mathrm{fb}^{-1}$$fb-1. For models with strict left-right symmetry, and assuming only one $$\mathrm {N}_{\ell }$$Nℓ flavor contributes significantly to the $$\mathrm {W}_{\mathrm {R}}$$WR decay width, the region in the two-dimensional $$(M_{\mathrm {W}_{\mathrm {R}}}, M_{\mathrm {N}_{\ell }})$$(MWR,MNℓ) mass plane excluded at a 95 % confidence level extends to approximately $$M_{\mathrm {W}_{\mathrm {R}}} = 3.0\,\text {TeV} $$MWR=3.0TeV and covers a large range of neutrino masses below the $$\mathrm {W}_{\mathrm {R}}$$WR boson mass, depending on the value of $$M_{\mathrm {W}_{\mathrm {R}}}$$MWR. This search significantly extends the $$(M_{\mathrm {W}_{\mathrm {R}}}, M_{\mathrm {N}_{\ell }})$$(MWR,MNℓ) exclusion region beyond previous results.
119204233
Search for new physics in events with same-sign dileptons and b-tagged jets in pp collisions at $ \sqrt {s} = 7 $ TeV
A bstractA search for new physics is performed using isolated same-sign dileptons with at least two b-quark jets in the final state. Results are based on a 4.98 fb−1 sample of proton-proton collisions at a centre-of-mass energy of 7 TeV collected by the CMS detector. No excess above the standard model background is observed. Upper limits at 95% confidence level are set on the number of events from non-standard-model sources. These limits are used to set constraints on a number of new physics models. Information on acceptance and efficiencies are also provided so that the results can be used to confront additional models in an approximate way.
86624438
Search for massive resonances decaying into pairs of boosted bosons in semi-leptonic final states at s$$ \sqrt{s} $$ = 8 TeV
A bstractA search for new resonances decaying to WW, ZZ, or WZ is presented. Final states are considered in which one of the vector bosons decays leptonically and the other hadronically. Results are based on data corresponding to an integrated luminosity of 19.7 fb−1 recorded in proton-proton collisions at s$$ \sqrt{s} $$ = 8 TeV with the CMS detector at the CERN LHC. Techniques aiming at identifying jet substructures are used to analyze signal events in which the hadronization products from the decay of highly boosted W or Z bosons are contained within a single reconstructed jet. Upper limits on the production of generic WW, ZZ, or WZ resonances are set as a function of the resonance mass and width. We increase the sensitivity of the analysis by statistically combining the results of this search with a complementary study of the all-hadronic final state. Upper limits at 95% confidence level are set on the bulk graviton production cross section in the range from 700 to 10 fb for resonance masses between 600 and 2500 GeV, respectively. These limits on the bulk graviton model are the most stringent to date in the diboson final state.

32172622
Measurement of WZ and ZZ production in pp collisions at $$\sqrt{s} = 8\,\text {TeV} $$s=8TeV in final states with b-tagged jets
Measurements are reported of the WZ and ZZ production cross sections in proton-proton collisions at $$\sqrt{s} = 8$$s=8$$\,\text {TeV}$$TeV in final states where one Z boson decays to b-tagged jets. The other gauge boson, either W or Z, is detected through its leptonic decay (either $$\mathrm {W}\rightarrow \mathrm {e}\nu $$W→eν, $$\mathrm {\mu }\nu $$μν or $$\mathrm {Z}\rightarrow \mathrm {e}^+\mathrm {e}^-$$Z→e+e-, $$\mathrm {\mu ^+}\mathrm {\mu ^-}$$μ+μ-, or $${\nu }\overline{\nu }$$νν¯). The results are based on data corresponding to an integrated luminosity of 18.9 fb$$^{-1}$$-1 collected with the CMS detector at the Large Hadron Collider. The measured cross sections, $$\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm {W}\mathrm {Z}) = 30.7 \pm 9.3\,\text {(stat.)} \pm 7.1\,\text {(syst.)} \pm 4.1\,\text {(th.)} \pm 1.0\,\text {(lum.)} \,\text {pb} $$σ(pp→WZ)=30.7±9.3(stat.)±7.1(syst.)±4.1(th.)±1.0(lum.)pb and $$\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm {Z}\mathrm {Z}) = 6.5 \pm 1.7\,\text {(stat.)} \pm 1.0\,\text {(syst.)} \pm 0.9\,\text {(th.)} \pm 0.2\,\text {(lum.)} \,\text {pb} $$σ(pp→ZZ)=6.5±1.7(stat.)±1.0(syst.)±0.9(th.)±0.2(lum.)pb, are consistent with next-to-leading order quantum chromodynamics calculations.
43759506
Bounds on the CP asymmetry in b --> sgamma decays.
We have measured the CP asymmetry A(CP) identical with[gamma(b-->sgamma)-gammab-->sgamma)]/[gamma(b-->sgamma)+gamma(b-->sgamma)] to be A(CP) = (-0.079+/-0.108+/-0.022) (1.0+/-0.030), implying that, at 90% confidence level, A(CP) lies between -0.27 and +0.10. These limits rule out some extreme non-standard-model predictions, but are consistent with most, as well as with the standard model.
124472455
Search for diphoton events with large missing transverse momentum in 7 TeV proton-proton collision data with the ATLAS detector
A search for diphoton events with large missing transverse momentum has been performed using proton-proton collision data at is root s = 7 TeV recorded with the ATLAS detector, corresponding to an integrated luminosity of 4.8 fb(-1). No excess of events was observed above the Standard Model prediction and model-dependent 95% confidence level exclusion limits are set. In the context of a generalised model of gauge-mediated supersymmetry breaking with a bino-like lightest neutralino of mass above 50 GeV, gluinos (squarks) below 1.07 TeV (0.87 TeV) are excluded, while a breaking scale Lambda below 196 TeV is excluded for a minimal model of gauge-mediated supersymmetry breaking. For a specific model with one universal extra dimension, compactification scales 1/R < 1.40 TeV are excluded. These limits provide the most stringent tests of these models to date. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.
12501278
An upgraded version of the generator BCVEGPY2.0 for hadronic production of Bc meson and its excited states
An upgraded version of the package BCVEGPY2.0: [C.-H. Chang, J.-X. Wang, X.-G. Wu, Comput. Phys. Common. 174 (2006) 241] is presented, which works under LINUX system and is named as BCVEGPY2.1. With the version and a GNU C compiler additionally, users may simulate the B-c-events in various experimental environments very conveniently. It has been manipulated in better modularity and code reusability (less cross communication among various modules) than BCVEGPY2.0 has. Furthermore, in the upgraded version a special execution is arranged as that the GNU command make compiles a requested code with the help of a master makefile in main code directory, and then builds an executable file with the default name run. Finally, this paper may also be considered as an erratum, i.e., typo errors in BCVEGPY2.0 and corrections accordingly have been listed.
120805024
Search for First Generation Scalar Leptoquarks in pp Collisions at $\sqrt{s}=7$ TeV with the ATLAS Detector
We report a search for first generation scalar leptoquarks using 1.03 fb−1 of proton–proton collisions data produced by the Large Hadron Collider at and recorded by the ATLAS experiment. Leptoquarks are sought via their decay into an electron or neutrino and a quark, producing events with two oppositely charged electrons and at least two jets, or events with an electron, missing transverse momentum and at least two jets. Control data samples are used to validate background predictions from Monte Carlo simulation. In the signal region, the observed event yields are consistent with the background expectations. We exclude at 95% confidence level the production of first generation scalar leptoquark with masses when assuming the branching fraction of a leptoquark to a charged lepton is equal to 1.0 (0.5).
29287213
Observation of psi(3770) --> pi pi J/psi and measurement of Gamma ee[psi(2S)].
We observe signals for the decays psi(3770) --> XJ/psi from data acquired with the CLEO detector operating at the CESR e+ e- collider with square root of s = 3773 MeV. We measure the following branching fractions Beta(psi(3770) --> XJ/psi and significances: (189 +/- 20 +/- 20) x 10(-5) (11.6sigma) for X = pi+ pi-, (80 +/- 25 +/- 16) x 10(-5) (3.4sigma) for X = pi0 pi0, and (87 +/- 33 +/- 22) x 10(-5) (3.5sigma) for X = eta, where the errors are statistical and systematic, respectively. The radiative return process e+ e- --> gamma psi(2S) populates the same event sample and is used to measure Gamma ee[psi(2S)] = (2.54 +/- 0.03 +/- 0.11) keV.