11013185
Phenomenology of not-so-heavy neutral leptons: The NuTeV anomaly, lepton universality, and non-universal neutrino-gauge couplings
The Standard Model (SM) predictions of these parameters based on a global fit to non-NuTeV data, cited as [g L]SM = 0.3042 and [g 2 R]SM = 0.0301 in Ref. [1], differ from the NuTeV result by 3σ in g L. The NuTeV value for g L in Eq. (1) is smaller than its SM prediction, reflecting the fact that the ratios Rν = σ(νμN → νμX)/σ(νμN → μ X) and Rν = σ(νμN → νμX)/σ(νμN → μ X) were smaller than expected by the SM. Thus, possible new physics explanations of the NuTeV anomaly would be those that suppress the neutral current cross sections over the charged current cross sections, or enhance the charged current cross sections over the neutral current cross sections. To this end, two classes of models have been devised. Models of the first class suppress Rν and Rν through new neutrino-quark interactions, mediated by leptoquarks or extra U(1) gauge bosons (Z ’s), which interfere either destructively with the Z-exchange amplitude, or constructively with the W -exchange amplitude [2]. To maintain agreement between the SM and non-NuTeV data, the new interactions must selectively interfere with the νμN (νμN) scattering process, but little else. This severely restricts the types of interactions that may be introduced. Models of the second class suppress the Zνν coupling by mixing the neutrino with heavy gauge singlet states (neutrissimos, i.e. right-handed neutrinos) [3, 4, 5]. For instance, if the SU(2)L active ν is a linear combination of two mass eigenstates with mixing angle θ,
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.
119454228
A Simple parameterization of matter effects on neutrino oscillations
We present simple analytical approximations to matter-effect corrected effective neutrino mixingangles and effective mass-squared-differences. The expressions clarify the dependence of oscillation probabilities in matter to the mixing angles and mass-squared-differences in vacuum, and are useful for analyzing long-baseline neutrino oscillation experiments.
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.
119450303
Indirect probes of new physics
We summarize the indirect effects of new physics in a variety of processes. We consider precision electroweak measurements, the $g-2$ of the muon, rare decays, meson mixing, CP violation, lepton number violating interactions, double beta decay, and the electric dipole moments of atoms, molecules, and the neutron. We include discussions of both model independent and dependent analyses where applicable.
16033618
Precision Tests of Electroweak Physics
We review the current status of precision electroweak measurements andthe constraints they impose on new physics. We perform a model inde-pendent analysis using the STU–formalism of Ref. 1, and then discusshow the Z–pole data from LEP and SLD can be used to constrain modelsthat are not covered within that framework.
140060327
Nb-3_Al high field accelerator magnet \&
136296280
Characteristics of round and extracted strands of Nb3Al Rutherford cable
Long Nb{sub 3}Al strands with copper stabilizer are promising for future high field accelerator magnets. A 1.2 kilometer Nb{sub 3}Al strand with Cu stabilizer was fabricated at the National Institute for Materials Science in Japan. Using this strand a 30 meter Cu stabilized Nb{sub 3}Al Rutherford cable was made for the first time by a collaboration of NIMS and Fermilab. The Nb{sub 3}Al strands extracted from cable with a relatively low packing factor showed almost no J{sub c} degradation. But the extracted strands from the highly compacted cable showed some degradation in both J{sub c} and n value, which may be caused by local separation of the copper stabilizer. Still, its J{sub c} degradation is lower than that of typical Nb{sub 3}Sn strands. The current limit due to magnetic instability in low field is about 500 A at 4.2 K. The magnetization of the strands, which was measured with balanced coils at 4.2 K, showed large flux jumps, usually around 1.5 T. This value is much larger than the B{sub c2} (4.2 K) of the Nb matrix, which is around 0.4 Tesla. The magnetic instability of the Nb{sub 3}Al strand at low field is not completely understood, but it might be explained by the superconducting coupling current through the Nb matrix.
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.