54186542
Position and Momentum Uncertainties of the Normal and Inverted Harmonic Oscillators under the Minimal Length Uncertainty Relation
p 2 ). This deformed commutation relation leads to the minimal length uncertainty relationx � (~/2)(1/�p + ��p), which implies thatx � 1/�p at smallp whilex � �p at largep. We find that the uncertainties of the energy eigenstates of the normal harmonic oscillator (m > 0), derived in Ref. (1), only populate thex � 1/�p branch. The other branch, �x � �p, is found to be populated by the energy eigenstates of the 'inverted' harmonic oscillator (m p 2(~ 2 /k|m|) 1/4 . Correspondence with the classical limit is also discussed.
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.
444650
Oblique corrections to the W width.
The lowest-order expression for the partial $W$ width to $e \nu ,~\Gamma (W \to e \nu) = G_\mu M_W^3 /(6 \pi \sqrt{2})$, has no oblique radiative corrections from new physics if the measured $W$ mass is used. Here $G_\mu = (1.16639 \pm 0.00002) \times 10^{-5}$ GeV/$c^2$ is the muon decay constant. For the present value of $M_W = (80.14 \pm 0.27)$ GeV/$c^2$, and with $m_t = 140$ GeV$/c^2$, one expects $\Gamma (W \to e \nu) = (224.4 \pm 2.3)$ MeV. The total width $\Gamma_{\rm tot}(W)$ is also expected to lack oblique corrections from new physics, so that $\Gamma_{\rm tot} (W)/ \Gamma (W \to e \nu) = 3 + 6 [1 + \{\alpha_s (M_W)/\pi \}]$. Present data are consistent with this prediction.
42982683
Analytical and numerical study of the Schwinger-Dyson equation with four-fermion coupling.
L'equation d'echelle habillee de Schwinger-Dyson, pour la self-energie du fermion Σ(p 2 ), avec un terme de couplage a 4 fermions additionnel, est etudiee de facon a la fois analytique et numerique. L'analyse est limitee aux theories asymptotiquement libres avec une hierarchie grande entre l'echelle de confinement Λ c et le cutoff ultraviolet Λ. On obtient la dependance de la masse dynamique Σ o =Σ(0) et le condensat de fermion vis-a-vis de la force de couplage a 4 fermions λ. Il existe une force de couplage a 4 fermions critique λ 2 , de sorte que dans la region λ λ 2 , la masse dynamique Σ 0 soit de l'ordre du cutoff Λ
215736286
STATUS AND PERSPECTIVE OF THE NB3AL DEVELOPMENT IN JAPAN
The RHQT process enables to form a stoichiometric Nb3Al with fine-grain structures via a bcc supersaturated solid solution and so that a large Jc is achieved over the whole range of magnetic fields without trading off the excellent strain tolerance. A long-length of RHQ processing has been established, and a rectangular but Cu stabilized Nb3Al strand is about to be commercially available for NMR uses. Another stabilization technique has been developed and likely applicable to accelerator uses. Research activities at the KEK with respect to the low field Jc characterization are also described.
134388752
Design study of 15-Tesla RHQT Nb3Al block type dipole magnet
The design study of the block type 15-Tesla RHQT Nb{sub 3}Al dipole magnet, and its merits over Nb{sub 3}Sn magnets are presented. The copper stabilized RHQT Nb{sub 3}Al strand is now becoming commercially available for the application to the accelerator magnets. A 1 mm diameter RHQT Nb{sub 3}Al strand with filament size about 50 {mu}, non-copper Jc about 1000 A/mm{sup 2} at 15 Tesla at 4.2K, copper ratio of 50%, can now be produced over several hundred meters. The stress and strain characteristics of the Nb{sub 3}Al strand are superior to the Nb{sub 3}Sn strand. Another advantage is that it can tolerate a longitudinal strain up to 0.55%. The RHQT Nb{sub 3}Al Rutherford cable will have less chance of contamination of the stabilizer, compared to Nb{sub 3}Sn cable. These characteristics of the RHQT Nb{sub 3}Al will be beneficial for designing and producing 15-Tesla dipole magnets. An example 15-Tesla magnet cross section, utilizing the RHQT Nb{sub 3}Sn strand is presented. A systematic investigation on RHQT Nb{sub 3}Al strands, its Rutherford cables, and building a small racetrack magnet for cable testing are proposed.