Fixed-order and merged parton-shower predictions for WW and WWj production at the LHC including NLO QCD and EW corrections

First, we present a combined analysis of pp $$ \to {\mu}^{+}{v}_{\mu }{\mathrm{e}}^{-}{\overline{v}}_{\mathrm{e}} $$ → μ + v μ e − v ¯ e and pp $$ \to {\mu}^{+}{v}_{\mu }{\mathrm{e}}^{-}{\overline{v}}_{\mathrm{e}}\mathrm{j} $$ → μ + v μ e − v ¯ e j at next-to-leading order, including both QCD and electroweak corrections. Second, we provide all-order predictions for pp $$ \to {\mu}^{+}{v}_{\mu }{\mathrm{e}}^{-}{\overline{v}}_{\mathrm{e}}+ $$ → μ + v μ e − v ¯ e + jets using merged parton-shower simulations that also include approximate EW effects. A fully inclusive sample for WW production is compared to the fixed-order computations for exclusive zero- and one-jet selections. The various higher-order effects are studied in detail at the level of cross sections and differential distributions for realistic experimental set-ups. Our study confirms that merged predictions are significantly more stable than the fixed-order ones in particular regarding ratios between the two processes.

Queer solidarities: New activisms erupting at the intersection of structural precarity and radical misrecognition

This article investigates the relationship between exposure to structural injustice, experiences of social discrimination, psychological well being, physical health, and engagement in activist solidarities for a large, racially diverse and inclusive sample of 5,860 LGBTQ/Gender Expansive youth in the United States. Through a participatory action research design and a national survey created by an intergenerational research collective, the “What’s Your Issue?” survey data are used to explore the relationships between injustice, discrimination and activism; to develop an analysis of how race and gender affect young people’s vulnerabilities to State violence (in housing, schools and by the police), and their trajectories to activism, and to amplify a range of “intimate activisms” engaged by LGBTQ/GE youth with powerful adults outside their community, and with often marginalized peers within. The essay ends with a theoretical appreciation of misrecognition as structural violence; activism as a racialized and gendered response to injustice, and an elaborated archive of “intimate activisms” engaged with dominant actors and within community, by LGBTQ/GE youth who have been exiled from home, school, state protection and/or community and embody, nevertheless, “willful subjectivities”.

Study of ${\rm B^0_s}$ oscillations and measurement of the inclusive b semileptonic branching ratio in ALEPH

An improved search for [Formula: see text] oscillations is performed on b hadron decays collected by the ALEPH experiment during 1991-1995 with three analyses, using respectively an inclusive sample of semileptonic b decays, a sample of [Formula: see text] events and a sample of fully reconstructed [Formula: see text] decays. This update results in a significant improvement over previously published results. A precise measurement of the inclusive semileptonic b branching ratio is performed, by exploiting the correlation between the lepton charge and an inclusive charge estimator in the opposite hemisphere, thus allowing to reduce the dependence on the b-decay modelling.

Quarkonium Production at LEP with the OPAL Detector

Evidence for the production of ϒ mesons in hadronic Z0 decays has recently been reported by the OPAL experiment at LEP. ϒ mesons are identified from their decays into e+e- and μ+μ- pairs. These decays provide a clear signature, since the e+e- and μ+ μ- background with invariant mass around 10 GeV/c2 is found to be small. In the first part of this report, a summary of the ϒ analysis is presented and possible production mechanisms are discussed. In the second part, studies on charmonium production are presented. Charmonium studies are based on an inclusive sample of J/ψ candidates, used to derive inclusive J/ψ and ψ′ rates, and the prompt J/ψ rate as well. Finally, since prompt J/ψ mesons are expected to be produced at LEP by the same production mechanisms as for the ϒ, a more general discussion on quarkonium production via fragmentation processes is presented.