Analysis and calibration of absorptive images of Bose-Einstein condensate at non-zero temperatures

We describe the method allowing quantitative interpretation of absorptive images of mixtures of BEC and thermal atoms which reduces possible systematic errors associated with evaluation of the contribution of each fraction. By using known temperature dependence of the BEC fraction, the analysis allows precise calibration of the fitting results. The developed method is verified in two different measurements and compares well with theoretical calculations and with measurements performed by another group.Comment: 17 pages, 8 figure

Optically-induced lensing effect on a Bose-Einstein condensate expanding in a moving lattice

We report the experimental observation of a lensing effect on a Bose-Einstein condensate expanding in a moving 1D optical lattice. The effect of the periodic potential can be described by an effective mass dependent on the condensate quasi-momentum. By changing the velocity of the atoms in the frame of the optical lattice we induce a focusing of the condensate along the lattice direction. The experimental results are compared with the numerical predictions of an effective 1D theoretical model. Besides, a precise band spectroscopy of the system is carried out by looking at the real-space propagation of the atomic wavepacket in the optical lattice.Comment: 5 pages, 4 figures; minor changes applied and typos corrected; a new paragraph added; some references updated; journal reference adde

Polarizabilities of the 87Sr Clock Transition

In this paper, we propose an in-depth review of the vector and tensor polarizabilities of the two energy levels of the 87Sr clock transition whose measurement was reported in [P. G. Westergaard et al., Phys. Rev. Lett. 106, 210801 (2011)]. We conduct a theoretical calculation that reproduces the measured coefficients. In addition, we detail the experimental conditions used for their measurement in two Sr optical lattice clocks, and exhibit the quadratic behaviour of the vector and tensor shifts with the depth of the trapping potential and evaluate their impact on the accuracy of the clock

Free expansion of a Bose-Einstein condensate at the presence of a thermal cloud

We investigate numerically the free-fall expansion of a $^{87}$Rb atoms condensate at nonzero temperatures. The classical field approximation is used to separate the condensate and the thermal cloud during the expansion. We calculate the radial and axial widths of the expanding condensate and find clear evidence that the thermal component changes the dynamics of the condensate. Our results are confronted against the experimental data

Application of an Error Correction Model in Assessment and Forecasting of Energy Consumption in the European Union

In the following framework, efforts of building a model of energy consumption with regard to basic macroeconomic factors such as gross domestic product (GDP), consumer price index (CPI), and demographic variables, have been undertaken. Above-mentioned model, thanks to an error correction mechanism enables to indicate short- and long-term relations between analyzed variables.The spatial and time sample which was chosen for the research, includes data from 1980 – 2005 from the European Union countries. The application of such cross sample and decomposition of absolute term, enables to indicate certain general regularities in analyzed phenomenon, and also typical of particular countries. From empirical point of view, the created model can be used in preparation of simulations and forecasts with planned energy consumption on the national and international level.Предпринята попытка построения модели потребления энергии с учетом макроэкономических факторов, таких как ВВП, индекс цен потребителя, и демографических данных. Предлагаемая модель позволяет с помощью механизма коррекции ошибок определить кратко- и долгосрочные отношения между анализируемыми переменными. Использована пространственно-временная выборка данных с 1980 по 2005 г. по странам Европейского Союза. Применение такой перекрестной выборки и разбиение временного периода позволяет определить некоторые общие закономерности анализируемых явлений, а также закономерности, типичные для определенных стран. Созданная модель может быть использована для подготовки процедур моделирования и прогнозирования планируемого энергопотребления на национальном и международном уровнях.Здійснено спробу побудувати модель споживання енергії з урахуванням макроекономічних факторів, таких як ВВП, індекс цін споживача, та демографічних даних. Запропонована модель дозволяє за допомогою механізму виправлення похибок визначити коротко- і довгострокові стосунки між змінними, що аналізуються. Використано просторово-часову вибірку даних з 1980 по 2005 р. по країнам Європейського Союзу. Застосування такої перехресної вибірки та розкладання часового періоду дозволяє визначити деякі загальні закономірності явища, що аналізується, а також закономірності, типові для визначених країн. Розроблену модель можна використовувати для підготовки процедур моделювання та прогнозування енергоспоживання, що планується, на національному та міжнародному рівнях

Comparison of the Symbiotic Fauna of the Family Plethodontidae in the Ouachita Mountains of Western Arkansas

During the spring of 1985, 101 salamanders representing six host species (29 Plethodon ouachitae, 25 P. caddoensis, 6 P. fourchensis, 23 P. serratus, 13 Desmognathus brimleyorum, and 5 P. glutinosus glutinosus) were collected from six localities in three counties in Arkansas (Polk, Scott, and Montgomery) and examined for symbionts. With the exception of Hannemania dunni, all symbionts recovered from the first five species listed constitute new host records, and the endoparasitic fauna in all species establish new locality records. Examinations revealed one or more species of parasites in 82% of the hosts. Eight species of symbionts (3 nematode, 1 trematode, 1 cestode, 1 protozoan, 1 arthropod, and 1 cystacanth acanthocephalon) were recovered. Conclusions are based on the three host species examined in the largest numbers. Thelandros magnavulvularis and H. dunni were the most commonly occurring parasites, found in five and four host species respectively. Cepedietta michiganensis was restricted to P. ouachitae and Brachycoelium storeriae to P. caddoensis. Hannemania dunni was absent in P. serratus

Procjena povratka investicija za predloženo rabljenje solarnih sustava u Poljskoj

This paper focuses on the assessment of possibilities to subsidize the purchase and installation of solar collectors in Poland by government or local government grants and special funds designed for this purpose. It analysis of costs and profits resulting from the application of solar installations in the process of heat generation for household requirements, by calculating the payback time, with taking into account prices of other energy carriers and the above mentioned subsidies. Collectors at present are manufactured solely from metals (copper, aluminium, Al-Mg alloys). The use of these materials is tied to considerable energy demand and the production technology is complex. This affects the economy of running a solar device.Članak je usmjeren na procjenu mogućnosti novčane potpore nabavke instalacija solarnih kolektora u Poljskoj od vlade ili lokalnih pokrovitelja te posebni fondovi utemeljeni u tu svrhu. Analizirani su troškovi i dobit kao rezultat primjene solarnih instalacija u procesima zagrijavanja po zahtjevima, proračuna povratka investicije, uzimajući u obzir cijene računa ostalih, tj. više drugih usporednih energija. Sadašnji kolektori ustrojeni su od metala (bakra, aluminija, Al-Mg legure). Rabljenje ovih materijala je u svezi energetskim zahtjevima i proizvodnom tehnologijom. Utjecaji ekonomije ovisni su o solarnim uređajima

Non-fermi liquid scaling in CeRhSn

We have recently shown that CeRhSn exhibits non-Fermi liquid temperaturę dependences in its low-temperature physical properties. Here we suggest that the non-Fermi liquid behavior observed in CeRhSn may be due to the existence of a Griffiths phase in the vicinity of a quantum critical point, based on electrical resistivity, magnetic susceptibility, and specific heat measurements. For CeRhSn, the low-temperature scaling of bulk properties (C/T oc y oc T _1+A, where A < 1) is masked by an anomaly at about 6 K, which is of magnetic origin