A search is conducted for a low-mass charged Higgs boson produced in a top quark decay and subsequently decaying into a charm and a strange quark. The data sample was recorded in proton-proton collisions at s=13  TeV by the CMS experiment at the LHC and corresponds to an integrated luminosity of 35.9  fb-1. The search is performed in the process of top quark pair production, where one top quark decays to a bottom quark and a charged Higgs boson and the other to a bottom quark and a W boson. With the W boson decaying to a charged lepton (electron or muon) and a neutrino, the final state comprises an isolated lepton, missing transverse momentum, and at least four jets, of which two are tagged as b jets. To enhance the search sensitivity, one of the jets originating from the charged Higgs boson is required to satisfy a charm tagging selection. No significant excess beyond standard model predictions is found in the dijet invariant mass distribution. An upper limit in the range 1.68%–0.25% is set on the branching fraction of the top quark decay to the charged Higgs boson and bottom quark for a charged Higgs boson mass between 80 and 160 GeV.

A search is conducted for a low-mass charged Higgs boson produced in a top quark decay and subsequently decaying into a charm and a strange quark. The data sample was recorded in proton-proton collisions at $\\sqrt{s}=$ 13 TeV by the CMS experiment at the LHC and corresponds to an integrated luminosity of 35.9 fb$^{-1}$. The search is performed in the process of top quark pair production, where one top quark decays to a bottom quark and a charged Higgs boson, and the other to a bottom quark and a W boson. With the W boson decaying to a charged lepton (electron or muon) and a neutrino, the final state comprises an isolated lepton, missing transverse momentum, and at least four jets, of which two are tagged as b jets. To enhance the search sensitivity, one of the jets originating from the charged Higgs boson is required to satisfy a charm tagging selection. No significant excess beyond standard model predictions is found in the dijet invariant mass distribution. An upper limit in the range 1.68-0.25% is set on the branching fraction of the top quark decay to the charged Higgs boson and bottom quark for a charged Higgs boson mass between 80 and 160 GeV.

The second-order Fourier coefficients ($v_2$) characterizing the azimuthal distribution of $\Upsilon$(1S) and $\Upsilon$(2S) mesons arising from PbPb collisions at $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV are studied. The $\Upsilon$ mesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The data set was collected in 2018 and corresponds to an integrated luminosity of 1.7 nb$^{-1}$. The scalar product method is used to extract the $v_2$ coefficients of the azimuthal distribution. Results are reported for the rapidity range $|y|\lt$ 2.4, with the transverse momentum 0 $\lt p_\mathrm{T} \lt$ 50 GeV/$c$, and in three centrality ranges of 10-30, 30-50 and 50-90%. In contrast to the J/$\psi$ mesons, no azimuthal anisotropy is observed for the $\Upsilon$ mesons.

Article history: Received 3 October 2019 Received in revised form 31 March 2020 Accepted 1 April 2020 Available online 7 April 2020 Editor: M. Doser

We describe a search for Z boson pair production in p (cid:1) p collisions at ffiffiffi s p ¼ 1 : 96 TeV with the D0 detector at the Fermilab Tevatron Collider using a data sample corresponding to an integrated luminosity of 2 : 7 fb (cid:1) 1 . Using the final state decay ZZ ! ‘ þ ‘ (cid:1) (cid:1) (cid:1) (cid:1) (where ‘ ¼ e or (cid:2) ) we find a signal with a 2.6 standard deviations significance (2.0 expected) corresponding to a cross section of (cid:3) ð p (cid:1) p ! ZZ þ X Þ ¼ 2 : 01 (cid:2) 0 : 93 ð stat Þ (cid:2) 0 : 29 ð sys Þ pb .