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The strong coupling constant $alpha_s$ and the heavy-quark masses, $m_c$, $m_b$, $m_t$ are extracted simultaneosly with the parton distribution functions (PDFs) in the updated ABM12 fit including recent data from CERN-SPS, HERA, Tevatron, and the LHC. The values of begin{eqnarray} onumber alpha_s(M_Z)&=&0.1147pm0.0008~({rm exp.)}, onumber m_c(m_c)&=&1.252pm 0.018~({rm exp.})~{rm GeV}, onumber m_b(m_b)&=&3.83pm0.12~({rm exp.})~{rm GeV}, onumber m_t(m_t)&=&160.9pm1.1~({rm exp.})~{rm GeV} end{eqnarray} are obtained with the $overline{MS}$ heavy-quark mass definition being employed throughout the analysis.
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We perform global fits to the moments of semileptonic B decay distributions and extract |V_cb|, the heavy quark masses, and the non-perturbative parameters of the heavy quark expansion. We include NNLO perturbative corrections and recent determinations of the charm mass, and discuss how they improve the precision of the global fit. In particular, using the m_c determination of Ref.[11] we get m_b^kin=4.541(23) GeV and |V_cb|=(42.42+- 0.86) 10^{-3}. We also discuss the implications of the new fits for the normalization of rare B decays, the zero-recoil sum rule in B-> D* l nu, and the inclusive determination of |V_ub|.
The quark and charged lepton masses and the angles and phase of the CKM mixing matrix are nicely reproduced in a model which assumes SU(3)xSU(3) flavour symmetry broken by the v.e.v.s of fields in its bi-fundamental representation. The relations among the quark mass eigenvalues, m_u/m_c approx m_c/m_t approx m^2_d/m^2_s approx m^2_s/m^2_b approx Lambda^2_{GUT}/M^2_{Pl}, follow from the broken flavour symmetry. Large tan(beta) is required which also provides the best fits to data for the obtained textures. Lepton-quark grandunification with a field that breaks both SU(5) and the flavour group correctly extends the predictions to the charged lepton masses. The seesaw extension of the model to the neutrino sector predicts a Majorana mass matrix quadratically hierarchical as compared to the neutrino Dirac mass matrix, naturally yielding large mixings and low mass hierarchy for neutrinos.
We present comprehensive global fits of supersymmetric (SUSY) models from the Global and Modular Beyond-the-Standard-Model Inference Tool (GAMBIT) collaboration, based on arXiv:1705.07935 and arXiv:1705.07917. We investigate several variants of the minimal supersymmetric standard model, a fully constrained version (CMSSM) with universal scalar ($m_0$), gaugino ($m_{1/2}$) and trilinear masses ($A_0$) at the gauge coupling unification scale, a similar model that is relaxed by adding an extra parameter for the soft Higgs masses (NUHM1), another where the soft Higgs masses are also split (NUHM2) and finally a weak scale MSSM7 model. We use the public GAMBIT global fitting framework and take into account all relevant data to reveal the regions of parameter space with the highest likelihood. Our results reveal that all models have very heavy scenarios that are well out of reach of the LHC, but will be probed by forthcoming dark matter experiments, as well as a stop-co-annihilation region which has better prospects for detection in collider experiments. The stau co-annihilation region is excluded from the CMSSM at $2 sigma$ but is present in the NUHM1 and NUHM2 variants. Finally by relaxing constraints in the NUHM1, NUHM2 and MSSM7 we see additional regions appear: lighter chargino co-annihilation region, sbottom co-annihilation and $h/Z$ funnels.
We consider a simple extension of the electroweak theory, incorporating one $SU(2)_L$ doublet of colour-octet scalars with Yukawa couplings satisfying the principle of minimal flavour violation. Using the HEPfit package, we perform a global fit to the available data, including all relevant theoretical constraints, and extract the current bounds on the model parameters. Coloured scalars with masses below 1.05 TeV are already excluded, provided they are not fermiophobic. The mass splittings among the different (charged and CP-even and CP-odd neutral) scalars are restricted to be smaller than 20 GeV. Moreover, for scalar masses smaller than 1.5 TeV, the Yukawa coupling of the coloured scalar multiplet to the top quark cannot exceed the one of the SM Higgs doublet by more than 80%. These conclusions are quite generic and apply in more general frameworks (without fine tunings). The theoretical requirements of perturbative unitarity and vacuum stability enforce relevant constraints on the quartic scalar potential parameters that are not yet experimentally tested.
A brief overview of the global DGLAP analyses of the nuclear parton distribution functions is given. Although all the current global nPDF sets describe $R_{F_2}^A(x,Q^2)$ well in the large-$x$ region where the data exist, variations between their parton distributions can be substantial.
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