47 research outputs found

    The e+e- -> Z gamma gamma -> q q gamma gamma Reaction at LEP and Constraints on Anomalous Quartic Gauge Boson Couplings

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    The cross section of the process e^+ e^- -> Z \gamma\gamma -> qq \gamma \gamma is measured with 215 pb^-1 of data collected with the L3 detector during the final LEP run at centre-of-mass energies around 205 GeV and 207 GeV. No deviation from the Standard Model expectation is observed. The full data sample of 713 pb^-1, collected above the Z resonance, is used to constrain the coefficients of anomalous quartic gauge boson couplings to: -0.02 GeV^-2 < a_0/\Lambda^2 < 0.03 GeV^-2 and -0.07 GeV^-2 < a_c/\Lambda^2 < 0.05 GeV^-2, at 95% confidence level

    CP Violation in τ3πντ\tau\rightarrow 3\pi\nu_\tau

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    We consider CP violating effects in the decays τ(3π)ντ\tau\rightarrow (3\pi)\nu_\tau where both the JP=1+{\rm J}^{\rm P}=1^+ resonance, a1a_1, and JP=0{\rm J}^{\rm P}=0^- resonance, π\pi^\prime, can contribute. The interference between the a1a_1 and π\pi^\prime resonances can lead to enhanced CP-violating asymmetries whose magnitudes depend crucially on the π\pi^\prime decay constant, fπf_{\pi^\prime}. We make an estimate of fπf_{\pi^\prime} with a simplified chiral Lagrangian coupled to a massive pseudoscalar field, and we compare the estimates from the non-relativistic quark model and from the QCD sum rule with the estimate from the `mock' meson model. We then estimate quantitatively the size of CP-violating effects in a multi-Higgs-doublet model and scalar-leptoquark models. We find that, while CP-violating effects in the scalar-leptoquark models may require more than 101010^{10} τ\tau leptons, CP-violating effects from the multi-Higgs-doublet model can be seen at the 2σ2\sigma level with about 10710^7 τ\tau leptons using the chiral Lagrangian estimate of fπ=(15)×103f_{\pi^\prime}=(1\sim 5)\times 10^{-3} GeV.Comment: Latex, 30 pages, 2 figures (not included). Three compressed postscript files of the paper available at ftp://ftp.kek.jp/kek/preprints/TH/TH-419/kekth419.ps.gz, Tau1.ps.gz, Tau2.ps.g

    Lives versus Livelihoods? Perceived economic risk has a stronger association with support for COVID-19 preventive measures than perceived health risk

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    This paper examines whether compliance with COVID-19 mitigation measures is motivated by wanting to save lives or save the economy (or both), and which implications this carries to fight the pandemic. National representative samples were collected from 24 countries (N = 25,435). The main predictors were (1) perceived risk to contract coronavirus, (2) perceived risk to suffer economic losses due to coronavirus, and (3) their interaction effect. Individual and country-level variables were added as covariates in multilevel regression models. We examined compliance with various preventive health behaviors and support for strict containment policies. Results show that perceived economic risk consistently predicted mitigation behavior and policy support—and its effects were positive. Perceived health risk had mixed effects. Only two significant interactions between health and economic risk were identified—both positive

    Study of the e+e- -> Z gamma gamma -> q q~ gamma gamma Process at LEP

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    The process e^+e^- -> Z gamma gamma -> q q~ gamma gamma is studied in 0.5 fb-1 of data collected with the L3 detector at centre-of-mass energies between 130.1 GeV and 201.7 GeV. Cross sections are measured and found to be consistent with the Standard Model expectations. The study of the least energetic photon constrains the quartic gauge boson couplings to -0.008 GeV-2 < a_0/\Lambda^2 < 0.005 GeV-2 and -0.007 GeV-2 < a_c/\Lambda^2 < 0.011 GeV-2, at 95% confidence level

    Addressing climate change with behavioral science: a global intervention tournament in 63 countries

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    Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions’ effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior—several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people’s initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors

    Addressing climate change with behavioral science:A global intervention tournament in 63 countries

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    Study of the W+W-gamma Process and Limits on Anomalous Quartic Gauge Boson Couplings at LEP

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    The process e+e- -> W+ W- gamma is studied using the data collected by the L3 detector at LEP. New results, corresponding to an integrated luminosity of 427.4 pb-1 at centre-of-mass energies from 192 GeV to 207 GeV, are presented. The W+W- gamma cross sections are measured to be in agreement with Standard Model expectations. No hints of anomalous quartic gauge boson couplings are observed. Limits at 95% confidence level are derived using also the process e+e- --> nu nubar gamma gamma

    Identifying important individual‐ and country‐level predictors of conspiracy theorizing: a machine learning analysis

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    Psychological research on the predictors of conspiracy theorizing—explaining important social and political events or circumstances as secret plots by malevolent groups—has flourished in recent years. However, research has typically examined only a small number of predictors in one, or a small number of, national contexts. Such approaches make it difficult to examine the relative importance of predictors, and risk overlooking some potentially relevant variables altogether. To overcome this limitation, the present study used machine learning to rank-order the importance of 115 individual- and country-level variables in predicting conspiracy theorizing. Data were collected from 56,072 respondents across 28 countries during the early weeks of the COVID-19 pandemic. Echoing previous findings, important predictors at the individual level included societal discontent, paranoia, and personal struggle. Contrary to prior research, important country-level predictors included indicators of political stability and effective government COVID response, which suggests that conspiracy theorizing may thrive in relatively well-functioning democracies

    Supersize my identity: when thoughts of contracting swine flu boost one's patriotic identity

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    Pandemics are socially threatening situations that rapidly spread across large regions. Thinking of contracting dangerous diseases can potentially evoke fear and death-related thoughts. The aim of the present work was to investigate how individuals respond to fear associated with contracting a pandemic disease (i.e., swine flu). In accordance with the mortality salience hypothesis of terror management theory (Greenberg, Pyszczynski, & Solomon, 1986), we predicted that individuals concerned with contracting swine flu would demonstrate greater investment in cultural worldviews (i.e., patriotism) in response to death anxiety. The implications of these findings for understanding global issues in domains related to health and politics are discussed
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