Constraint on the number of quark generations through mass matrices

Erdem, Recai


Constraints on the Higgs boson width from off-shell production and decay to Z-boson pairs
Khachatryan, V.; et. al. (Elsevier BV, 2014-09-01)
Constraints are presented on the total width of the recently discovered Higgs boson, Gamma(H), using its relative on-shell and off-shell production and decay rates to a pair of Z bosons, where one Z boson decays to an electron or muon pair, and the other to an electron, muon, or neutrino pair. The analysis is based on the data collected by the CMS experiment at the LHC in 2011 and 2012, corresponding to integrated luminosities of 5.1 fb(-1) at a center-of-mass energy root s = 7 TeV and 19.7 fb(-1) at root s...
Constraints on the spin-parity and anomalous HVV couplings of the Higgs boson in proton collisions at 7 and 8 TeV
Khachatryan, V.; et. al. (American Physical Society (APS), 2015-07-01)
The study of the spin-parity and tensor structure of the interactions of the recently discovered Higgs boson is performed using the H -> ZZ, Z gamma*, gamma*gamma* -> 4l, H -> WW -> l(nu)l(nu), and H -> gamma gamma decay modes. The full data set recorded by the CMS experiment during the LHC run 1 is used, corresponding to an integrated luminosity of up to 5.1 fb(-1) at a center-of-mass energy of 7 TeV and up to 19.7 fb(-1) at 8 TeV. A wide range of spin-two models is excluded at a 99% confidence level or hi...
Model independent analysis of rare, exclusive b-meson decays
Çakmak, Mehmet Kerim; Savcı, Mustafa; Department of Physics (2004)
Using the general, model indepenent form of the effective Hamiltonian, the general expressions of the longitudinal, normal and transversal polarization asymmetries for l+ and l- for the effective B -> K(K*)l+l- decays has been calculated. Existence of regions of Wilson coefficients for which the branching ratio coincides with the Standard Model result, while the lepton polarizations differ from the standard model prediction is expected. Hence, studying lepton polarizations in these regions of Wilson coeffic...
Dependence on pseudorapidity and on centrality of charged hadron production in PbPb collisions at root s(NN)=2.76 TeV
Sirunyan, A. M.; et. al. (Springer Science and Business Media LLC, 2011-08-01)
A measurement is presented of the charged hadron multiplicity in hadronic PbPb collisions, as a function of pseudorapidity and centrality, at a collision energy of 2.76 TeV per nucleon pair. The data sample is collected using the CMS detector and a minimum-bias trigger, with the CMS solenoid off. The number of charged hadrons is measured both by counting the number of reconstructed particle hits and by forming hit doublets of pairs of layers in the pixel detector. The two methods give consistent results. Th...
Limits on the Higgs boson lifetime and width from its decay to four charged leptons
Khachatryan, V.; et. al. (American Physical Society (APS), 2015-10-01)
Constraints on the lifetime and width of the Higgs boson are obtained from H -> ZZ -> 4l events using data recorded by the CMS experiment during the LHC run 1 with an integrated luminosity of 5.1 and 19.7 fb(-1) at a center-of-mass energy of 7 and 8 TeV, respectively. The measurement of the Higgs boson lifetime is derived from its flight distance in the CMS detector with an upper bound of tau(H) 3.5 x 10(-9) MeV. The measurement of the width is obtained from an off-shell production technique, generalized t...
Citation Formats
R. Erdem, “Constraint on the number of quark generations through mass matrices,” Ph.D. - Doctoral Program, Middle East Technical University, 1991.