Anomalies in the X-ray diffuse scattering from Cr-doped V2O3 at the high temperature metal—insulator transition

Several anomalies in the X-ray diffuse scattering of Cr-doped V₂O₃ have been observed in proximity of the high temperature metal—insulator transition. It is speculated that charge density waves might be involved. The original interpretation in terms of a Mott transition is brought up again for discussion.     

Elastic scattering of20Ne on24Mg

High spin states in⁸⁵Rb and⁸⁵Sr were populated in the reactions⁷⁶Ge(¹²C,p2n) and⁷⁶Ge(¹²C,3n), respectively. The lifetimes of twelve states were measured via the recoil distance Doppler shift technique. The positive parity bands in both nuclei associated with theg _9/2 orbit exhibit decrasingE2 strengths for increasing spin value marking the onset of multiparticle excitation.     

νμp and νμn charged-current interactions unfolded from high energy νμ interactions in neon

We have developed a method to separate $\text{ν}$n and $\text{ν}$p interactions from antineutrino-neon interactions by using the final state electric charge. We present the distributions of the scaling variables x and y for $\text{ν}$n and $\text{ν}$p interactions separately , along with the $\text{ν}$n and $\text{ν}$p cross section ratios as a function of x and y. We obtain a total $\text{ν}$n to $\text{ν}$p cross section ratio of 0.45± 0.08. Our results are consistent with the predictions of the simple quark parton model.     

Abrupt change between smooth and oscillatory angular distributions in 16O induced transfer reactions on 26Mg

Angular distributions from (¹⁶O, ¹⁵N) and (¹⁶O, ¹⁴C) reactions on ²⁶Mg have been measured at both 45 and 60 MeV bombarding energies. The two reactions have approximately the same peak cross sections, but the (¹⁶O, ¹⁵N) distributions vary smoothly with angle while the (¹⁶O, ¹⁴C) cross section oscillates strongly as a function of angle. It is shown that the angular distribution shape is strongly dependent on the steepness of the form factor and that the magnitude of the (¹⁶O, ¹⁴C) cross section is very sensitive to the absorptive part of the optical potential.     

Elimination of nitrate interference in the trace détermination of sulphate as hydrogen sulphide

The microdetermination of sulphate by reduction to hydrogen sulphide, determined colorimetrically as Methylene Blue, is subject to interference from nitrate ion. This interference is eliminated by adding zinc acetate and igniting samples at 320 degrees for one hr.     

High-resolution spectroscopy on trapped molecular ions in rotating electric fields: A new approach for measuring the electron electric dipole moment

High-resolution molecular spectroscopy is a sensitive probe for violations of fundamental symmetries. Symmetry violation searches often require, or are enhanced by, the application of an electric field to the system under investigation. This typically precludes the study of molecular ions due to their inherent acceleration under these conditions. Circumventing this problem would be of great benefit to the high-resolution molecular spectroscopy community since ions allow for simple trapping and long interrogation times, two desirable qualities for precision measurements. Our proposed solution is to apply an electric field that rotates at radio frequencies. We discuss considerations for experimental design as well as challenges in performing precision spectroscopic measurements in rapidly time-varying electric fields. Ongoing molecular spectroscopy work that could benefit from our approach is summarized. In particular, we detail how spectroscopy on a trapped diatomic molecular ion with a ground or metastable ³Δ₁ level could prove to be a sensitive probe for a permanent electron electric dipole moment (eEDM).     

Bottomonium above deconfinement in lattice nonrelativistic QCD

We study the temperature dependence of bottomonium for temperatures in the range 0.4T(c) < T < 2.1T(c), using nonrelativistic dynamics for the bottom quark and full relativistic lattice QCD simulations for Nf = 2 light flavors on a highly anisotropic lattice. We find that the Υ is insensitive to the temperature in this range, while the χb propagators show a crossover from the exponential decay characterizing the hadronic phase to a power-law behavior consistent with nearly free dynamics at T ? 2T(c).     

Fast mixing for independent sets,colorings, and other models on trees

We study the mixing time of the Glauber dynamics for general spin systems on the regular tree, including the Ising model, the hard‐core model (independent sets), and the antiferromagnetic Potts model at zero temperature (colorings). We generalize a framework, developed in our recent paper (Martinelli, Sinclair, and Weitz, Tech. Report UCB//CSD‐03‐1256, Dept. of EECS, UC Berkeley, July 2003) in the context of the Ising model, for establishing mixing time O(nlog n), which ties this property closely to phase transitions in the underlying model. We use this framework to obtain rapid mixing results for several models over a significantly wider range of parameter values than previously known, including situations in which the mixing time is strongly dependent on the boundary condition. We also discuss applications of our framework to reconstruction problems on trees. © 2006 Wiley Periodicals, Inc. Random Struct. Alg., 2007