119197432
Proton decay and the origin of quark and lepton mixing
A bstractIt was recently proposed that all flavor mixing has a single source, namely the mixing of the three quark and lepton families with “extra” vectorlike fermions in 5 + $ \overline{5} $ multiplets of SU(5). This was shown to lead to several testable predictions including neutrino masses and CP-violating phases. Here it is shown that the mixing angles within grand unified fermion multiplets are also predicted. Proton decay branching ratios would thus give several independent tests of the model. Certain model parameters could be determined independently from the quark and lepton spectrum and from proton decay.
118658279
A simple grand unified relation between neutrino mixing and quark mixing
A bstractIt is proposed that all flavor mixing is caused by the mixing of the three quark and lepton families with vectorlike fermions in $ 5+\bar{5} $ multiplets of SU(5). This simple assumption implies that both VCKM and UM N S are generated by a single matrix. The entire 3 × 3 complex mass matrix of the neutrinos Mv is then found to have a simple expression in terms of two complex parameters and an overall scale. Thus, all the presently unknown neutrino parameters are predicted. The best fits are for θatm ≲ 40°. The leptonic Dirac CP phase is found to be somewhat greater than π.
120528491
Tau-Charm factory project at Beijing
Abstract The Tau-Charm Factory (TCF) is a proposed high luminosity e + e − collider at the threshold region of the production of τ and charm. It could provide many precision measurements and search for new phenomena in the flavor physics. IHEP, Beijing, is an ideal cite to build a TCF. The status of the feasibility study of Beijing Tau-Charm Factory (BTCF) is reported.
119270909
Wall crossing and instantons in compactified gauge theory
We calculate the leading weak-coupling instanton contribution to the modulispace metric of $ \mathcal{N} = 2 $ supersymmetric Yang-Mills theory with gauge group SU(2) compactified on $ {\mathbb{R}^3} \times {S^1} $. The results are in precise agreement with the semiclassical expansion of the exact metric recently conjectured by Gaiotto, Moore and Neitzke based on considerations related to wall-crossing in the corresponding four-dimensional theory.
14512709
The present day mass function in the central region of the Arches cluster
We study the evolution of the mass function in young and dense star clusters by means of direct N-body simulations. Our main aim is to explain the recent observations of the relatively flat mass function observed near the centre of the Arches star cluster. In this region, the power-law index of the mass function for stars more massive than about 5–6 M⊙ is larger than the Salpeter value by about unity, whereas further out, and for the lower mass stars, the mass function resembles the Salpeter distribution. We show that the peculiarities in the Arches mass function can be explained satisfactorily without primordial mass segregation. We draw two conclusions from our simulations: (i) the Arches initial mass function is consistent with a Salpeter slope down to ∼1 M⊙, and (ii) the cluster is about half-way towards core collapse. The cores of other star clusters with characteristics similar to those of the Arches are expected to show similar flattening in the mass functions for the high-mass (≳5 M⊙) stars.
119213771
A 5d/3d duality from relativistic integrable system
A bstractWe propose and prove a new exact duality between the F-terms of supersymmetric gauge theories in five and three dimensions with adjoint matter fields. The theories are compactified on a circle and are subject to the Ω deformation. In the limit proposed by Nekrasov and Shatashvili, the supersymmetric vacua become isolated and are identified with the eigenstates of a quantum integrable system. The effective twisted superpotentials are the Yang-Yang functional of the relativistic elliptic Calogero-Moser model. We show that they match on-shell by deriving the Bethe ansatz equation from the saddle point of the five-dimensional partition function. We also show that the Chern-Simons terms match and extend our proposal to the elliptic quiver generalizations.
119200064
Notes on wall crossing and instanton in compactified gauge theory with matter
We study the quantum effects on the Coulomb branch of $ \mathcal{N} = 2 $ SU(2) super-symmetric Yang-Mills with fundamental matters compactified on $ {\mathbb{R}^3} \times {S^1} $, and extract the explicit perturbative and leading non-perturbative corrections to the moduli space metric predicted from the recent work of Gaiotto, Moore and Neitzke on wall-crossing [1]. We verify the predicted metric by computing the leading weak coupling instanton contribution to the four fermion correlation using standard field theory techniques, and demonstrate perfect agreement. We also demonstrate how previously known three dimensional quantities can be recovered in appropriate small radius limit, and provide a simple geometric picture from brane construction.