Measurement of differential cross-sections of a top quark produced in association with a W boson at √s=13 TeV with ATLAS

The differential cross-section for the production of a W boson in association with a top quark is measured for several particle-level observables. The measurements are performed using 36.1fb−1 of pp collision data collected with the ATLAS detector at the LHC in 2015 and 2016. Differential cross-sections are measured in a fiducial phase space defined by the presence of two charged leptons and exactly one jet matched to a b-hadron, and are normalised with the fiducial cross-section. Results are found to be in good agreement with predictions from several Monte Carlo event generators

Outcome for esophageal cancer following treatment with chemotherapy and radiotherapy but not esophagectomy: nonsurgical treatment of esophageal cancer

Urs Zingg1,2, Dennis DiValentino1, Alexander McQuinn1, Ahmad Mardzuki1, Sarah K Thompson2,  Christos S Karapetis1,3, David I Watson11Flinders University Department of Surgery, Flinders Medical Centre, Bedford Park, South Australia, Australia; 2Discipline of Surgery, University of Adelaide, Adelaide, South Australia, Australia; 3Department of Medical Oncology, Flinders Medical Centre, Bedford Park, South Australia, AustraliaBackground: More than 50% of patients with esophageal cancer are not suitable for surgery. The aim of this study was to analyze the outcome of patients undergoing standard nonsurgical treatment.Methods: Data of all patients undergoing nonsurgical treatment for esophageal cancer were identified from a prospective database.Results: Seventy-five patients were treated for localized disease, and 52 for metastatic disease at diagnosis. Except for age, which was higher in patients without metastases, there were no significant differences between the patients with vs. without metastatic disease. Kaplan–Meier analysis showed a median survival of 10.8 months for all patients. There was a significant difference in survival (p < 0.001) between the groups with versus without metastases, with median survival in the patients without metastases 13.6 months versus 6.5 months in patients with metastases. Patients undergoing nonsurgical treatment for localized disease had a five-year survival of 12%. No significant difference between adenocarcinoma and squamous cell carcinoma was identified. Subanalysis of patients who received chemoradiotherapy revealed similar results to the overall group of patients.Conclusion: In patients with localized disease at diagnosis, long-term survival can be achieved in some patients, whereas five-year survival is rare in patients who present with metastatic disease.Keywords: nonsurgical treatment, esophageal cancer, chemoradiotherapy, metastases, surviva

Search for heavy ZZ resonances in the l(+) l(-) l(+) l(-) and l(+) l(-) nu(nu)over-bar final states using proton-proton collisions at root s=13 TeV with the ATLAS detector

A search for heavy resonances decaying into a pair of $Z$ bosons leading to $\ell^+\ell^-\ell^+\ell^-$ and $\ell^+\ell^-\nu\bar\nu$ final states, where $\ell$ stands for either an electron or a muon, is presented. The search uses proton proton collision data at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 36.1 fb$^{-1}$ collected with the ATLAS detector during 2015 and 2016 at the Large Hadron Collider. Different mass ranges for the hypothetical resonances are considered, depending on the final state and model. The different ranges span between 200 GeV and 2000 GeV. The results are interpreted as upper limits on the production cross section of a spin 0 or spin 2 resonance. The upper limits for the spin 0 resonance are translated to exclusion contours in the context of Type I and Type II two-Higgs-doublet models, while those for the spin 2 resonance are used to constrain the Randall Sundrum model with an extra dimension giving rise to spin 2 graviton excitations

Search for heavy ZZ resonances in the +−+− and +−νν¯ final states using proton–proton collisions at √s = 13 TeV with the ATLAS detector

A search for heavy resonances decaying into a pair of Z bosons leading to +−+− and +−νν¯ final states, where stands for either an electron or a muon, is presented. The search uses proton–proton collision data at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 36.1 fb−1 collected with the ATLAS detector during 2015 and 2016 at the Large Hadron Collider. Different mass ranges for the hypothetical resonances are considered, depending on the final state and model. The different ranges span between 200 and 2000 GeV. The results are interpreted as upper limits on the production cross section of a spin-0 or spin-2 resonance. The upper limits for the spin-0 resonance are translated to exclusion contours in the context of Type-I and Type-II two-Higgs-doublet models, while those for the spin-2 resonance are used to constrain the Randall–Sundrum model with an extra dimension giving rise to spin-2 graviton excitations

Search for W ' -> t(b)over-bar in the lepton plus jets final state in proton-proton collisions at a centre-of-mass energy of root s=8 TeV with the ATLAS detector

A search for new charged massive gauge bosons, called W', is performed with the ATLAS detector at the LHC, in proton-proton collisions at a centre-of-mass energy of root s = 8 TeV, using a dataset corresponding to an integrated luminosity of 20.3 fb(-1). This analysis searches for W' bosons in the W' -> t (b) over tilde decay channel in final states with electrons or muons, using a multivariate method based on boosted decision trees. The search covers masses between 0.5 and 3.0 TeV, for right-handed or left-handed W' bosons. No significant deviation from the Standard Model expectation is observed and limits are set on the W' -> t (b) over bar cross-section times branching ratio and on the W'-boson effective couplings as a function of the W'-boson mass using the CLs procedure. For a left-handed (right-handed) W' boson, masses below 1.70 (1.92) TeV are excluded at 95% confidence level. Published by Elsevier B.V