Loading of bosons in optical lattices into the p band

We present a method for transferring bosonic atoms residing on the lowest s-band of an optical lattice to the first excited p-bands. Our idea hinges on resonant tunneling between adjacent sites of accelerated lattices. The acceleration effectively shifts the quasi-bound energies on each site such that the system can be cast into a Wannier-Stark ladder problem. By adjusting the acceleration constant, a situation of resonant tunneling between the s- and p-bands is achievable. Within a mean-field model, considering 87Rb atoms, we demonstrate population transfer from the s- to the p-bands with around 95 % efficiency. Nonlinear effects deriving from atom-atom interactions, as well as coupling of the quasi bound Wannier-Stark states to the continuum, are considered.Comment: 8 pages, 7 figure

Research of metal solidification in zero-g state

An experiment test apparatus that allows metal melting and resolidification in the three seconds available during free fall in a drop tower was built and tested in the tower. Droplets (approximately 0.05 cm) of pure nickel and 1090 steel were prepared in this fashion. The apparatus, including instrumentation, is described. As part of the instrumentation, a method for measuring temperature-time histories of the free floating metal droplets was developed. Finally, a metallurgical analysis of the specimens prepared in the apparatus is presented

DISTANCE EDUCATION IN AGRICULTURAL ECONOMICS: AN ASSESSMENT OF STUDENT ACCEPTANCE AND PERFORMANCE.

This paper reports an analysis of student evaluation of and performance in three agricultural economics classes offered at distance by audio-visual connection in real time. Multiple regression analyses of student questionnaire data are used to examine the relationship between student attributes and their evaluation of and performance in the distance-offered course.Teaching/Communication/Extension/Profession,

Rabi oscillations in a quantum dot-cavity system coupled to a non-zero temperature phonon bath

We study a quantum dot strongly coupled to a single high-finesse optical microcavity mode. We use a rotating wave approximation method, commonly used in ion-laser interactions, tegether with the Lamb-Dicke approximation to obtain an analytic solution of this problem. The decay of Rabi oscillations because of the electron-phonon coupling are studied at arbitrary temperature and analytical expressions for the collapse and revival times are presented. Analyses without the rotating wave approximation are presented by means of investigating the energy spectrum.Comment: 7 pages, 5 figures; Revised versio

Thermomagnetic analysis of meteorites. 3: C3 and C4 chondrites

Thermomagnetic analysis on all of the C3 and C4 chondrites, conducted under conditions of controlled oxygen fugacity, indicates the presence of a thermally unstable component in at least 5 of the C3 chondrites which upon heating results in magnetite production. This unstable component is most likely troilite (FeS). The presence of the unstable substance may affect the estimation of paleointensities in meteorites which contain it. Our results indicate that Grosnaja, Ornans, Kainsaz, Felix, and Warrenton are likely to be less complicated for paleointensity determinations than the other C3 chondrites. Both C4 chondrites should lead to reliable results

Identifying Potential Breeding Areas of Short-Eared Owls Prior to Nesting Using Roadside Surveys to Detect Courtship and Territoriality Behavior: A Comparison of Visual and Audio Techniques

We piloted a roadside survey technique for detecting Short-eared Owls during the courtship period in western Montana.  Thirty-five surveys were conducted between 2009 and 2012 and were timed to coincide with pair-formation and courtship behavior. Short-eared Owls perform courtship flights and vocalizations which can be observed and heard during the crepuscular period.  Surveys were designed to compare visual and audio survey techniques.  Visual surveys occurred during the crepuscular period at the end of civil twilight and were immediately followed by a nocturnal audio survey.  Visual survey techniques accounted for over 91% (N=240) of all detections.  Detections associated with audio survey techniques were almost always associated with survey points where at least one owl was detected during visual survey.  Nearly three-quarters of visual detections (N=220) occurred between 30 and 70 min before the end of civil twilight.  Over 75% of visual detections and 90% of nocturnal detections occurred in areas where vegetation was uncut and ungrazed and most frequently associated with vegetation heights greater than approximately 60cm.  Short-eared Owls were never detected in areas where livestock was present.  We recommend visual surveys during the courtship to identify potential breeding areas prior to the onset of incubation

Thermomagnetic analysis of meterorites. 4: Ureilites

Samples of all available ureilites have been analyzed thermomagnetically. For three of the six (Dyalpur, Goalpara and Havero) evidence was found for only low-nickel metallic-iron as the magnetic component and the (saturation magnetization vs, temperature) curves were reversible. In the Novo Urei ureilite, magnetite in addition to low-nickel metallic-iron was indicated and again the Js-T curve was reversible. For the two badly weathered ureilites, Dingo Pup Donga and North Haig, indication was also found that both initial magnetite and low-nickel metallic-iron were present. However, the Js-T curves were somewhat irreversible and the final saturation magnetization was 20% and 50% greater than initially for North Haig and Dingo Pup Donga, respectively. This behavior is interpreted to be the result of magnetite production from a secondary iron oxide during the experiment

Thermomagnetic analysis of meteorites, 2: C2 chondrites

Samples of all eighteen of the known C2 chondrites were analyzed thermomagnetically. For eleven of these, initial Fe3O4 content is low(generally 1%) and the J sub s-T curves are irreversible. The heating curves show variable and erratic behavior, whereas the cooling curves appear to be that of Fe3O4. The saturation moment after cooling is greater (up to 10 times larger) than it is initially. This behavior is interpreted to be the result of the production of magnetite from a thermally unstable phase--apparently FeS. Four of the remaining 7 C2 chondrites contain Fe3O4 as the only significant magnetic phase: initial magnetite contents range from 4 to 13 percent. The remaining three C2 chondrites contain iron or nickel-iron in addition to Fe3O4. These seven C2 chondrites show little evidence of the breakdown of a thermally unstable phase

A Relativistic Version of the Two-Level Atom in the Rest-Frame Instant Form of Dynamics

We define a relativistic version of the two-level atom, in which an extended atom is replaced by a point particle carrying suitable Grassmann variables for the description of the two-level structure and of the electric dipole. After studying the isolated system "atom plus the electro-magnetic field" in the electric-dipole representation as a parametrized Minkowski theory, we give its restriction to the inertial rest frame and the explicit form of the Poincar\'e generators. After quantization we get a two-level atom with a spin 1/2 electric dipole and the relativistic generalization of the Hamiltonians of the Rabi and Jaynes-Cummings models.Comment: 23 page