A search is presented for a heavy spin-1 resonance Formula omitted decaying to a top quark and a vector-like top quark partner Formula omitted in the lepton + jets final state. The search is ...performed using a data set of Formula omitted Formula omitted collisions at a centre-of-mass energy of 13 Formula omitted corresponding to an integrated luminosity of Formula omitted as recorded by the CMS experiment at the CERN LHC in the year 2016. The analysis is optimised for final states arising from the Formula omitted decay modes to a top quark and a Higgs or Formula omitted boson ( Formula omitted). The event selection makes use of resolved and merged top quark decay products, as well as decays of boosted Higgs bosons and Formula omitted and Formula omitted bosons using jet substructure techniques. No significant deviation from the standard model background expectation is observed. Exclusion limits on the product of the cross section and branching fraction for Formula omitted are presented for various combinations of the Formula omitted resonance mass and the vector-like Formula omitted quark mass. These results represent the most stringent limits to date for the decay mode Formula omitted. In a benchmark model with extra dimensions, invoking a heavy spin-1 resonance Formula omitted, masses of the Formula omitted between 1.5 and 2.3 Formula omitted and between 2.0 and 2.4 Formula omitted are excluded for Formula omitted masses of 1.2 and 1.5 Formula omitted, respectively.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The exclusive photoproduction of \\mathrm {\Upsilon }\mathrm {(nS)} \ meson states from protons, \\gamma \mathrm {p} \rightarrow \mathrm {\Upsilon }\mathrm {(nS)} \,\mathrm {p}\ (with \\mathrm ...{n}=1,2,3\), is studied in ultraperipheral \\mathrm {p}\Pb collisions at a centre-of-mass energy per nucleon pair of \\sqrt{\smash b{s_{_{\mathrm {NN}}} = 5.02\,\text {TeV} \. The measurement is performed using the \\mathrm {\Upsilon }\mathrm {(nS)} \rightarrow \mu ^+\mu ^-\ decay mode, with data collected by the CMS experiment corresponding to an integrated luminosity of 32.6\\,\text {nb}^{-1}\. Differential cross sections as functions of the \\mathrm {\Upsilon }\mathrm {(nS)} \ transverse momentum squared \p_{\mathrm {T}} ^2\, and rapidity y, are presented. The \\mathrm {\Upsilon (1S)}\ photoproduction cross section is extracted in the rapidity range \|y |< 2.2\, which corresponds to photon–proton centre-of-mass energies in the range \91<W_{\gamma \mathrm {p}} <826\,\text {GeV} \. The data are compared to theoretical predictions based on perturbative quantum chromodynamics and to previous measurements.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Measurements of normalized differential cross sections as functions of the multiplicity and kinematic variables of charged-particle tracks from the underlying event in top quark and antiquark pair ...production are presented. The measurements are performed in proton-proton collisions at a center-of-mass energy of 13 Formula omitted, and are based on data collected by the CMS experiment at the LHC in 2016 corresponding to an integrated luminosity of 35.9 Formula omitted. Events containing one electron, one muon, and two jets from the hadronization and fragmentation of Formula omitted quarks are used. These measurements characterize, for the first time, properties of the underlying event in top quark pair production and show no deviation from the universality hypothesis at energy scales typically above twice the top quark mass.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A search is presented for the single production of vector-like quarks in proton-proton collisions at Formula omitted. The data, corresponding to an integrated luminosity of 35.9 Formula omitted, were ...recorded with the CMS experiment at the LHC. The analysis focuses on the vector-like quark decay into a top quark and a Formula omitted boson, with one muon or electron in the final state. The mass of the vector-like quark candidate is reconstructed from hadronic jets, the lepton, and the missing transverse momentum. Methods for the identification of Formula omitted quarks and of highly Lorentz boosted hadronically decaying top quarks and Formula omitted bosons are exploited in this search. No significant deviation from the standard model background expectation is observed. Exclusion limits at 95% confidence level are set on the product of the production cross section and branching fraction as a function of the vector-like quark mass, which range from 0.3 to 0.03 Formula omitted for vector-like quark masses of 700 to 2000 Formula omitted. Mass exclusion limits up to 1660 Formula omitted are obtained, depending on the vector-like quark type, coupling, and decay width. These represent the most stringent exclusion limits for the single production of vector-like quarks in this channel.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A search is presented for decays of Formula omitted and Higgs bosons to a Formula omitted meson and a photon, with the subsequent decay of the Formula omitted to Formula omitted. The analysis uses ...data from proton-proton collisions with an integrated luminosity of 35.9 Formula omitted at Formula omitted collected with the CMS detector at the LHC. The observed limit on the Formula omitted decay branching fraction, assuming that the Formula omitted meson is produced unpolarized, is Formula omitted at 95% confidence level, which corresponds to a rate higher than expected in the standard model by a factor of 15. For extreme-polarization scenarios, the observed limit changes from Formula omitted to Formula omitted with respect to the unpolarized scenario. The observed upper limit on the branching fraction for Formula omitted where the Formula omitted meson is assumed to be transversely polarized is Formula omitted, a factor of 260 larger than the standard model prediction. The results for the Higgs boson are combined with previous data from proton-proton collisions at Formula omitted to produce an observed upper limit on the branching fraction for Formula omitted that is a factor of 220 larger than the standard model value.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Measurements of inclusive isolated-photon and photon+jet production in proton-proton collisions at
are presented. The analysis uses data collected by the CMS experiment in 2015, corresponding to an ...integrated luminosity of 2.26
. The cross section for inclusive isolated photon production is measured as a function of the photon transverse energy in a fiducial region. The cross section for photon+jet production is measured as a function of the photon transverse energy in the same fiducial region with identical photon requirements and with the highest transverse momentum jet. All measurements are in agreement with predictions from next-to-leading-order perturbative QCD.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A search is presented for a heavy pseudoscalar boson
decaying to a Z boson and a Higgs boson with mass of 125
. In the final state considered, the Higgs boson decays to a bottom quark and antiquark, ...and the Z boson decays either into a pair of electrons, muons, or neutrinos. The analysis is performed using a data sample corresponding to an integrated luminosity of 35.9
collected in 2016 by the CMS experiment at the LHC from proton-proton collisions at a center-of-mass energy of 13
. The data are found to be consistent with the background expectations. Exclusion limits are set in the context of two-Higgs-doublet models in the
boson mass range between 225 and 1000
.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A search for dark matter produced in association with a Higgs boson decaying to a pair of bottom quarks is performed in proton-proton collisions at a center-of-mass energy of 13
collected with the ...CMS detector at the LHC. The analyzed data sample corresponds to an integrated luminosity of 35.9
. The signal is characterized by a large missing transverse momentum recoiling against a bottom quark-antiquark system that has a large Lorentz boost. The number of events observed in the data is consistent with the standard model background prediction. Results are interpreted in terms of limits both on parameters of the type-2 two-Higgs doublet model extended by an additional light pseudoscalar boson
(2HDM+
) and on parameters of a baryonic
simplified model. The 2HDM+
model is tested experimentally for the first time. For the baryonic
model, the presented results constitute the most stringent constraints to date.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A top quark mass measurement is performed using
of LHC proton-proton collision data collected with the CMS detector at
. The measurement uses the
all-jets final state. A kinematic fit is performed to ...reconstruct the decay of the
system and suppress the multijet background. Using the ideogram method, the top quark mass (
) is determined, simultaneously constraining an additional jet energy scale factor (
). The resulting value of
is in good agreement with previous measurements. In addition, a combined measurement that uses the
lepton+jets and all-jets final states is presented, using the same mass extraction method, and provides an
measurement of
. This is the first combined
extraction from the lepton+jets and all-jets channels through a single likelihood function.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Combined measurements of the production and decay rates of the Higgs boson, as well as its couplings to vector bosons and fermions, are presented. The analysis uses the LHC proton-proton collision ...data set recorded with the CMS detector in 2016 at
, corresponding to an integrated luminosity of 35.9
. The combination is based on analyses targeting the five main Higgs boson production mechanisms (gluon fusion, vector boson fusion, and associated production with a
or
boson, or a top quark-antiquark pair) and the following decay modes:
,
,
,
,
, and
. Searches for invisible Higgs boson decays are also considered. The best-fit ratio of the signal yield to the standard model expectation is measured to be
, assuming a Higgs boson mass of
. Additional results are given for various assumptions on the scaling behavior of the production and decay modes, including generic parametrizations based on ratios of cross sections and branching fractions or couplings. The results are compatible with the standard model predictions in all parametrizations considered. In addition, constraints are placed on various two Higgs doublet models.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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