1,030 research outputs found

    Measurement of WZ and ZZ production in pp collisions at √s = 8 TeV in final states with b-tagged jets

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    Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited. Funded by SCOAP3 / License Version CC BY 4.0.Measurements are reported of the WZ and ZZ production cross sections in proton-proton collisions at s √ =8 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 W→eν , μν or Z→e + e − , μ + μ − , or νν ¯ ). The results are based on data corresponding to an integrated luminosity of 18.9 fb −1 collected with the CMS detector at the Large Hadron Collider. The measured cross sections, σ(pp→WZ)=30.7±9.3(stat.)±7.1(syst.)±4.1(th.)±1.0(lum.)pb and 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 calculationsBMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CS (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF(Germany);GSRT(Greece);OTKAand NIH(Hungary);DAEand DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Republic of Korea); LAS (Lithuania);MOE and UM(Malaysia); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS and RFBR (Russia); MESTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEPCenter, IPST, STAR and NSTDA(Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR (Ukraine); STFC (United Kingdom); DOE and NSF (USA)

    Social-demographic influence on first birth interval in China, 1980-1992

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    This study examines the delay between first marriage and first live birth in China among a sample of women who married between 1980 and 1992. Most couples in China only use contraception after the first child is born. Most sample women had their first child within 2 years of marriage. However, there are significant rural-urban differences in the first birth interval, indicating that there was most probably deliberate fertility regulation after marriage among many urban couples. Survival analysis shows that place of residence, level of education, age at first marriage and marriage cohort affect the first birth interval.DemographyPublic, Environmental & Occupational HealthSocial Sciences, BiomedicalPubMedSSCI6ARTICLE3315-3273

    Measurement of the ZZZZ production cross section in pppp collisions at s\sqrt{s} = 8 TeV using the ZZ++ZZ\to\ell^{-}\ell^{+}\ell^{\prime -}\ell^{\prime +} and ZZ+ννˉZZ\to\ell^{-}\ell^{+}\nu\bar{\nu} channels with the ATLAS detector

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    See paper for full list of authors - 55 pages in total, author list starting page 39, 9 figures, 11 tables, submitted to JHEP. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2014-16/International audienceA measurement of the ZZZZ production in the ++\ell^{-}\ell^{+}\ell^{\prime -}\ell^{\prime +} and +ννˉ\ell^{-}\ell^{+}\nu\bar{\nu} channels (=e,μ)(\ell = e, \mu) in proton--proton collisions at s=8\sqrt{s} = 8 TeV at the Large Hadron Collider at CERN, using data corresponding to an integrated luminosity of 20.3 fb1^{-1} collected by the ATLAS experiment in 2012 is presented. The fiducial cross sections for ZZ++ZZ\to\ell^{-}\ell^{+}\ell^{\prime -}\ell^{\prime +} and ZZ+ννˉZZ\to \ell^{-}\ell^{+}\nu\bar{\nu} are measured in selected phase-space regions. The total cross section for ZZZZ events produced with both ZZ bosons in the mass range 66 to 116 GeV is measured from the combination of the two channels to be 7.3±0.4(stat)±0.3(syst)±0.2(lumi)7.3\pm0.4\textrm{(stat)}\pm0.3\textrm{(syst)}\pm0.2\textrm{(lumi)} pb, which is consistent with the Standard Model prediction of 6.60.6+0.76.6^{+0.7}_{-0.6} pb. The differential cross sections in bins of various kinematic variables are presented. The differential event yield as a function of the transverse momentum of the leading ZZ boson is used to set limits on anomalous neutral triple gauge boson couplings in ZZZZ production

    Soft gluon resummation in the signal-background interference process of gg(→ h ∗) → ZZ

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    We present a precise theoretical prediction for the signal-background interference process of gg(→ h ∗) → ZZ, which is useful to constrain the Higgs boson decay width and to measure Higgs couplings to the SM particles. The approximate NNLO K-factor is in the range of 2.05 − 2.45 (1.85 − 2.25), depending on M ZZ , at the 8 (13) TeV LHC. And the soft gluon resummation can increase the approximate NNLO result by about 10% at both the 8 TeV and 13 TeV LHC. The theoretical uncertainties including the scale, uncalculated multi-loop amplitudes of the background and PDF+αs are roughly O(10%) at NNLL′. We also confirm that the approximate K-factors in the interference and the pure signal processes are the same

    Measurement of the ZZ production cross section in proton-proton collisions at √s=8 TeV using the ZZ → ℓ−ℓ+ℓ′−ℓ′+ and ZZ→ ℓ−ℓ+νν¯ decay channels with the ATLAS detector

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    A measurement of the ZZ production cross section in the ℓ−ℓ+ℓ′ −ℓ′ + and ℓ−ℓ+νν¯ channels (ℓ = e, μ) in proton-proton collisions at s=8TeV at the Large Hadron Collider at CERN, using data corresponding to an integrated luminosity of 20.3 fb−1 collected by the ATLAS experiment in 2012 is presented. The fiducial cross sections for ZZ → ℓ−ℓ+ℓ′ −ℓ′ + and ZZ→ ℓ−ℓ+νν¯ are measured in selected phase-space regions. The total cross section for ZZ events produced with both Z bosons in the mass range 66 to 116 GeV is measured from the combination of the two channels to be 7.3 ± 0.4(stat) ± 0.3(syst)− 0.1 − 0.2(lumi) pb, which is consistent with the Standard Model prediction of 6. 6− 0.6 + 0.7 pb. The differential cross sections in bins of various kinematic variables are presented. The differential event yield as a function of the transverse momentum of the leading Z boson is used to set limits on anomalous neutral triple gauge boson couplings in ZZ production.[Figure not available: see fulltext.] © 2017, The Author(s). SciVal Topic ProminenceWosScopusScopu

    Alkaid Cheng - HiggsHunting2022 - Talk in CDS

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    A combination of Higgs boson pair production and single Higgs production is performed using up to 139/fb of proton-proton collision data recorded with the ATLAS detector at a center-of-mass energy of √s = 13 TeV at the LHC. The combination includes the bbbb, bb and bbγγ decay channels from the Higgs boson pair production and the ZZ->4l, WW, γγ, tt, bb, VH, bb (boosted), bb (VBF) and bb (ttH) decay channels from the single Higgs boson production. The results are expressed in terms of the constraints on the Higgs boson trilinear self-coupling modifier κλ in two scenarios: 1. with all other coupling modifiers fixed to their SM values and 2. with the top coupling modifier κt profiled. In addition, a constraint contour on the (κλ, κt) is also presented

    Rock Concert Performance from ABBA to ZZ Top

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    This book presents an analysis of 100 rock concert performances and attempts to answer the question "What makes a truly great rock performance?" Author Peter Smith, an experienced concert goer, delves into his own recollections of experiencing rock performances over the last 50+ years and, with the support of his daughter, Laura Smith, analyzes 100 selected performances covering the themes of icons, persona, energy, fandom, venues, communities, politics, art-rock, authenticity and maturity. The approach taken is based upon qualitative analysis, reflection, and autoethnography. The selected performances cover a range of diverse acts such as the Rolling Stones, ABBA, Sex Pistols, Barbara Streisand, David Bowie, and the like

    Search for heavy resonances decaying to ZZ or ZW and axion-like particles mediating nonresonant ZZ or ZH production at √s = 13 TeV

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    © 2022, The Author(s).A search has been performed for heavy resonances decaying to ZZ or ZW and for axion-like particles (ALPs) mediating nonresonant ZZ or ZH production, in final states with two charged leptons (ℓ = e, μ) produced by the decay of a Z boson, and two quarks produced by the decay of a Z, W, or Higgs boson H. The analysis is sensitive to resonances with masses in the range 450 to 2000 GeV. Two categories are defined corresponding to the merged or resolved reconstruction of the hadronically decaying boson. The search is based on data collected during 2016–2018 by the CMS experiment at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb−1. No significant excess is observed in the data above the standard model background expectation. Upper limits on the production cross section of heavy, narrow spin-2 and spin-1 resonances are derived as functions of the resonance mass, and exclusion limits on the production of bulk graviton particles and W′ bosons are calculated in the framework of the warped extra dimensions and heavy vector triplet models, respectively. In addition, upper limits on the ALP-mediated diboson production cross section and ALP couplings to standard model particles are obtained in the framework of linear and chiral effective field theories. These are the first limits on nonresonant ALP-mediated ZZ and ZH production obtained by the LHC experiments. [Figure not available: see fulltext.

    Search for heavy resonances decaying to ZZ or ZW and axion-like particles mediating nonresonant ZZ or ZH production at ?s = 13 TeV

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    Abstract: A search has been performed for heavy resonances decaying to ZZ or ZW and for axion-like particles (ALPs) mediating nonresonant ZZ or ZH production, in final states with two charged leptons (? = e, ?) produced by the decay of a Z boson, and two quarks produced by the decay of a Z, W, or Higgs boson H. The analysis is sensitive to resonances with masses in the range 450 to 2000 GeV. Two categories are defined corresponding to the merged or resolved reconstruction of the hadronically decaying boson. The search is based on data collected during 2016–2018 by the CMS experiment at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb?1. No significant excess is observed in the data above the standard model background expectation. Upper limits on the production cross section of heavy, narrow spin-2 and spin-1 resonances are derived as functions of the resonance mass, and exclusion limits on the production of bulk graviton particles and W? bosons are calculated in the framework of the warped extra dimensions and heavy vector triplet models, respectively. In addition, upper limits on the ALP-mediated diboson production cross section and ALP couplings to standard model particles are obtained in the framework of linear and chiral effective field theories. These are the first limits on nonresonant ALP-mediated ZZ and ZH production obtained by the LHC experiments. [Figure not available: see fulltext.] © 2022, The Author(s)

    General lack of global dosage compensation in ZZ/ZW systems? Broadening the perspective with RNA-seq

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    Abstract Background Species with heteromorphic sex chromosomes face the challenge of large-scale imbalance in gene dose. Microarray-based studies in several independent male heterogametic XX/XY systems suggest that dosage compensation mechanisms are in place to mitigate the detrimental effects of gene dose differences. However, recent genomic research on female heterogametic ZZ/ZW systems has generated surprising results. In two bird species and one lepidopteran no evidence for a global dosage compensating mechanism has been found. The recent advent of massively parallel RNA sequencing now opens up the possibility to gauge the generality of this observation with a broader phylogenetic sampling. It further allows assessing the validity of microarray-based inference on dosage compensation with a novel technology. Results We here expemplify this approach using massively parallel sequencing on barcoded individuals of a bird species, the European crow (Corvus corone), where previously no genetic resources were available. Testing for Z-linkage with quantitative PCR (qPCR,) we first establish that orthology with distantly related species (chicken, zebra finch) can be used as a good predictor for chromosomal affiliation of a gene. We then use a digital measure of gene expression (RNA-seq) on brain transcriptome and confirm a global lack of dosage compensation on the Z chromosome. RNA-seq estimates of male-to-female (m:f) expression difference on the Z compare well to previous microarray-based estimates in birds and lepidopterans. The data further lends support that an up-regulation of female Z-linked genes conveys partial compensation and suggest a relationship between sex-bias and absolute expression level of a gene. Correlation of sex-biased gene expression on the Z chromosome across all three bird species further suggests that the degree of compensation has been partly conserved across 100 million years of avian evolution. Conclusions This work demonstrates that the study of dosage compensation has become amenable to species where previously no genetic resources were available. Massively parallele transcriptome sequencing allows re-assessing the degree of dosage compensation with a novel tool in well-studies species and, in addition, gain valuable insights into the generality of mechanisms across independent taxonomic group for both the XX/XY and ZZ/ZW system.</p
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