3003989
Universal torsion-induced interaction from large extra dimensions
We consider the Kaluza-Klein (KK) scenario in which only gravity exists in the bulk. Without the assumption of symmetric connection, the presence of brane fermions induces torsion. The result is a universal axial contact interaction that dominates those induced by KK gravitons. This enhancement arises from a large spin density on the brane. Using a global fit to Z-pole observables, we find the 3sigma bound on the scale of quantum gravity to be 28 TeV for n = 2. If Dirac or light sterile neutrinos are present, the data from SN1987A increase the bound to sqrt[n] M(S)>/=210 TeV.
17840929
Torsion constraints in the Randall-Sundrum scenario
Torsion appears due to fermions coupled to gravity and leads to the strongest particle physics bounds on flat extra dimensions. In this work, I consider torsion constraints in the case of a warped extra dimension with brane and bulk fermions. From current data I obtain a $3\ensuremath{\sigma}$ bound on the TeV-brane mass scale ${\ensuremath{\Lambda}}_{\ensuremath{\pi}}g~2.2 (10) \mathrm{TeV}$ for the anti-de Sitter curvature $k=1(0.01)$ in (reduced) Planck units. If Dirac or light sterile neutrinos reside on the brane, the bound increases to 17 (78) TeV.
118714441
The NMSSM and string theory
Abstract We study the possibility of constructing the NMSSM from the heterotic string. String-derived NMSSMs are much more rare than MSSMs due to the extra requirement that there exist a light singlet which couples to the Higgs pairs. They share the common feature that the singlet self-interactions are typically suppressed, leading to either the “decoupling” or the Peccei–Quinn limit of the NMSSM. In the latter case, the spectrum contains a light pseudoscalar which may be relevant to the MSSM fine-tuning problem. We provide a Z 6 heterotic orbifold example of the NMSSM with approximate Peccei–Quinn symmetry, whose origin lies in the string selection rules combined with our choice of the vacuum configuration.
1934772
The CKM phase in heterotic orbifold models
Abstract We consider properties of the CKM phase in the heterotic orbifold models. We find that at the renormalizable level the CKM phase vanishes identically for the prime orbifolds, whereas it can be nonzero for some nonprime orbifolds. In particular, we study in detail the Z 6 -I orbifold which allows for a nontrivial CKM phase and analyze the modular properties of the corresponding Jarlskog invariant. The CKM phase is shown to vanish if the moduli fields are stabilized at Im T i =±1/2.
119408018
Chargino Contributions to Epsilon and Epsilon-Prime
We analyze the chargino contributions to the K-\bar K mixing and epsilon-prime in the mass insertion approximation and derive the corresponding bounds on the mass insertion parameters. We find that the chargino contributions can significantly enlarge the regions of the parameter space where CP violation can be fully supersymmetric. In principle, the observed values of epsilon and epsilon-prime may be entirely due to the chargino -- up-squark loops.
3003989
Universal torsion-induced interaction from large extra dimensions
We consider the Kaluza-Klein (KK) scenario in which only gravity exists in the bulk. Without the assumption of symmetric connection, the presence of brane fermions induces torsion. The result is a universal axial contact interaction that dominates those induced by KK gravitons. This enhancement arises from a large spin density on the brane. Using a global fit to Z-pole observables, we find the 3sigma bound on the scale of quantum gravity to be 28 TeV for n = 2. If Dirac or light sterile neutrinos are present, the data from SN1987A increase the bound to sqrt[n] M(S)>/=210 TeV.
53956287
Upgrading the RF Cavity for U-70 Accelerator 0 -
This paper presents the results on the experimental invcstigation of the IJ-70 R.I: cavity with additional short circuit loops in thr RF magnetic field. These loops introduce a negative inductance impedanre into t,hc RF cavit,y circuit, and decreascx the cquivalcnt value of cavity inductance by about a factor of 10. This method allows at a low cost ‘,-fold increase the caparity of the accelerating gap for the 1!-70 cavity operating with the booster injection complex. ‘l’he lechnique of measuring the ferrite-dominated cavity pararncters is described.